Natural and Synthetic Food Additives and Preservatives;A Systematic Review of Their Implications for Food Quality Assurance,Shelf-Life,Food Safety,and Human Health

Abstract

Objective

The contemporary food industry relies heavily on additives and preservatives to mitigate spoilage, extend shelf-life, and uphold safety standards amid global supply chain pressures. This systematic review aims to synthesize and critically appraise the evidence from primary studies from 2020 to 2026 investigating natural and synthetic food additives and preservatives.

Methods

This systematic review followed PRISMA guidelines. Focusing on original empirical studies, the analysis contrasts natural additives/preservatives, e.g., plant extracts, bacteriocins, protein hydrolysates, etc., and synthetic additives/preservatives, e.g., benzoates, sorbates, nitrites, etc., followed by a comparative synthesis across four core domains of quality assurance, shelf-life extension, microbial safety, and human health outcomes.

Results

Drawing on 33 included studies, this systematic review found that natural additives/preservatives frequently match or surpass synthetics in targeted antimicrobial efficacy and oxidative stability while presenting fewer chronic toxicity concerns. However, regulatory revaluations highlight ongoing scrutiny of synthetic additives/preservatives. Original tables summarise key findings under subheadings such as Additive, Source, Food/Pharma Matrix, Shelf-life Extension, Microbial Reduction, Quality Assurance, Food Safety, Health Implications, Study Design, Limitations, etc. Findings demonstrate a shift toward hybrid clean label strategies, although gaps persist in long term human cohort data and scalability of novel bio preservatives.

Conclusion

Recent findings consistently signal a decisive shift toward hybrid preservation systems that integrate natural antimicrobials with smart delivery technologies while reducing reliance on synthetic additives. Policymakers and industries should priorities evidence based integration of additives/preservatives to balance their efficacy, food safety, and maintain consumer trust.

Graphical Abstract

Introduction

The contemporary food industry relies heavily on food additives and preservatives for preventing spoilage, extending product durability, and maintaining rigorous safety requirements amid global supply chain pressures. Primary experimental research on ready-to-eat hummus demonstrated that combinations of natural antimicrobials (such as 5% vinegar with 1.25% garlic or natamycin) achieved 2.2 to 3.2 log reductions in total aerobic counts, 1.8 to 3.1 log in Pseudomonas spp., and 1.4 to 2.1 log in lactic acid bacteria (LAB) by day 21 of refrigerated storage compared to controls, thereby extending shelf-life to approximately 30 days (versus ∼19 days for untreated or synthetic potassium sorbate samples) while preserving acceptable sensory quality and aligning with established microbial safety guidelines. ¹ A one-year primary microbiological investigation of 355 vacuum packaged cooked sausage samples collected across four seasons in a sustainable Brazilian food supply chain found that distribution related temperature fluctuations markedly reduced product durability (averaging 45.58 days in winter versus 26.33 days in summer), with spoilage driven primarily by yeasts (e.g., Trichosporon sp., Candida sp.) and Bacillus species; the study showed the continued necessity of controlled cold-chain conditions alongside manufacturing additives such as nitrates/nitrites to inhibit pathogens such as Clostridium botulinum and limit overall spoilage amid supply-chain pressures. ² Food preservation has evolved from rudimentary salting and drying to sophisticated chemical and biological interventions. Food additives are a broad category of natural or synthetic substances added to food to improve taste, texture, appearance, or shelf-life, while food preservatives are a specific type of additive designed solely to prevent spoilage, microbial growth, or oxidation. Essentially, all preservatives are additives, but not all additives are preservatives. In 2023, global food waste attributable to microbial spoilage exceeded 17% at retail and consumer levels, exacerbating food insecurity and environmental burdens. In this systematic review, “additives” refer to natural or synthetic substances added to improve the taste, texture, appearance, or shelf-life of food, while “preservatives” refer to natural or synthetic additives specifically designed to prevent spoilage, microbial growth, or oxidation, as well as to extend shelf-life. Natural additives are often derived from plant secondary metabolites, microbial fermentation by-products, or marine proteins, and offer antioxidant and antimicrobial properties rooted in evolutionary defence mechanisms. Synthetic counterparts, conversely, deliver consistent, cost-effective performance but raise questions regarding bioaccumulation and endocrine disruption.

Karanth et al ³ quantified microbial cross contamination pathways, demonstrating that intrinsic factors, such as pH and water activity, interact with extrinsic storage abuses to accelerate spoilage irrespective of type of preservative. Parallel work by Imtara et al ⁴ validated Psidium guajava leaf extract at 10% w/w as a viable substitute in semisolid matrices, achieving complete bacterial inhibition comparable to parabens but with reduced antifungal effects. Such evidence compels a revaluation of regulatory frameworks promulgated by EFSA, which continues reassessment of approved additives amid consumer demand for “natural” labelling.

The primary objective of this systematic review is to synthesize and critically appraise the evidence from primary studies published between 2020 and 2026 investigating natural and synthetic food additives and preservatives. This study seeks to elucidate their various implications for food quality assurance, shelf-life extension, food safety, and human health. Specifically, the systematic review: (1) assessed the efficacy of these additives in preserving sensory attributes, nutritional value, and physicochemical stability, thereby contributing to improved food quality assurance; (2) analysed mechanisms by which they inhibit microbial growth and oxidative degradation to prolong product shelf-life; (3) evaluated their contributions to mitigating foodborne illnesses, ensuring contaminant control, and supporting regulatory compliance for superior food safety; (4) examined the health related risks and benefits, including potential toxicity, allergenicity, and long term effects on consumer physiology; and (5) identify emerging trends, research gaps, and evidence-based strategies to optimize their application in the food industry while prioritizing public health and sustainability. Furthermore, this systematic review demonstrated (a) natural and synthetic food additives/preservatives, (b) impacts of natural and synthetic food additives/preservatives on quality assurance, (c) effects of natural and synthetic food additives/preservatives on food safety management, (d) health implications of natural and synthetic food additives/preservatives on public health, (e) biological properties of natural and synthetic food additives/preservatives, (f) made a comparative synthesis of the implications of natural versus synthetic food additives on food quality assurance, food safety, and human health, and (g) provided a future research directions, long term policy/industry implications, and opportunities for natural and hybrid preservation systems, along with key challenges and strategic recommendations for transition.

Method

Information Source and Search Strategy

This systematic review followed the PRISMA guidelines adapted for database heterogeneity. Searches were conducted on primary research publications published from 2020 to 2026 in PubMed, ScienceDirect, Scopus, MDPI, Frontiers, Wiley, Taylor and Francis, and PMC portals. Supplementary searches via Google Scholar and FAO/WHO/EFSA/USDA repositories yielded regulatory opinions anchored in contemporaneous primary data. The search was conducted by three reviewers. Boolean strings were applied as: “natural preservative” OR “synthetic additive” OR “plant extract” OR “bacteriocin” OR “benzoate” OR “sorbate” OR “nitrite” AND (“shelf-life” OR “food safety” OR “quality assurance” OR “human health” OR “toxicity”) OR (“food additive*” OR “food preservative*” OR “natural preservative*” OR “synthetic preservative*” OR “antimicrobial additive*” OR “antioxidant additive*”) AND (“shelf-life” OR “shelf-life” OR “storage stability” OR “food quality” OR “food safety” OR “microbial safety” OR “pathogen control”) AND (“natural” OR “plant extract*” OR “essential oil*” OR “bacteriocin*” OR “sorbate” OR “benzoate” OR “nitrite” OR “sulfite”) AND (“human health” OR “toxicity” OR “carcinogen*” OR “allergen*” OR “safety” OR “risk assessment” OR “chronic exposure”). We tailored strategies for each database with appropriate syntax, limits, and filters. Searches were conducted without language restriction initially, but only English full texts proceeded to screening.

Inclusion and Exclusion Criteria

Inclusion Criteria

Eligibility for inclusion in this systematic review was determined to capture only primary empirical investigations that directly advance understanding of the sophisticated roles of food additives and preservatives. Studies were included if they satisfied all of the following conditions:

(a) Published in English as original research articles, experimental studies, observational cohort or cross sectional analyses, in vitro/in vivo toxicity assays, between 2020 and 2026.

(b) Identified through systematic searches of the specified databases and repositories: PubMed, ScienceDirect, Scopus, MDPI, Frontiers, Wiley Online Library, Taylor and Francis Online, PubMed Central (PMC), and the official publication portals of the Food and Agriculture Organization (FAO), World Health Organization (WHO), European Food Safety Authority (EFSA), and United States Department of Agriculture (USDA).

(c) Focused explicitly on one or more natural (e.g., essential oils, phenolic extracts, bacteriocins, organic acids from plant or microbial sources) or synthetic (e.g., butylated hydroxyanisole, potassium sorbate, sodium nitrite, propyl gallate) food additives or preservatives.

(d) Reported quantitative or qualitative primary data on at least one of the study’s core outcome domains: (i) food quality assurance parameters, e.g., physicochemical stability, sensory attributes, colour retention, texture profile analysis, or nutritional retention; (ii) shelf-life extension, e.g., microbial enumeration, oxidative stability indices, water activity modulation, or accelerated shelf-life testing; (iii) food safety metrics, e.g., pathogen inactivation kinetics, antimicrobial spectrum, biofilm disruption, or hazard analysis critical control point integration; or (iv) human health implications, e.g., acute/chronic toxicity, genotoxicity, cytotoxicity, allergenicity, metabolic fate, epidemiological exposure outcome associations, or acceptable daily intake revaluations.

(e) Conducted in relevant matrices, such as food systems, model foods, simulated gastrointestinal conditions, cell lines, rodent or non-rodent animal models, or human volunteers, and provided sufficient methodological detail to permit critical appraisal.

(f) Only a few compelling reviews (less than 5%) containing information relevant to this study were included.

Duplicate removal and title/abstract screening reduced over 582 records to 127 full texts; 33 met inclusion after quality screening.

Exclusion Criteria

To maintain focus and methodological rigour, studies were excluded if they met any of the following conditions: classified as secondary literature/review/chapter; published before 2020; written in any language other than English; concerned solely with non-food applications; lacked primary empirical data; represented duplicate publications; or presented insufficient detail on additive identity, concentration, or outcome measurement to allow data synthesis.

Study Selection

Three independent reviewers screened titles and abstracts against eligibility criteria. We resolved disagreements through objective discussion/consensus. Full-text articles of potentially eligible records underwent the same review process. Reasons for exclusion at the full-text stage were based on irrelevant outcomes and insufficient additive specification. A PRISMA flow diagram illustrates the selection process, including numbers of records identified, screened, excluded, and included (Figure 1).

Figure 1.

PRISMA flowchart showing the number of selected publications

Data Extraction

Data extraction was executed independently by three reviewers following the PRISMA guidelines. Discrepancies were resolved through consensus discussion. A standardized, piloted data extraction form captured key information: additive class, matrix, design, log reductions, Thiobarbituric acid reactive substances (TBARS) values, shelf-life days, additive details (type, source, concentration, natural/synthetic classification), health biomarkers, etc. The narrative synthesis employed thematic grouping with critical appraisal of methodological rigour, including controls for confounding variables such as temperature abuse and initial microbial load. No meta analysis was done due to data heterogeneity; instead, vote counting and effect size directionality informed conclusions. For health studies, we extracted exposure assessment methods, confounders adjusted for, and statistical analyses. Three reviewers independently extracted data and objectively resolved discrepancies by consensus. When data were missing or unclear, we either extracted the identified data or excluded the article from the systematic review. For studies reporting multiple outcomes or time points, we prioritized those most relevant to shelf-life, safety, and chronic health effects.

Quality and Risk of Bias Assessment

Articles were checked for quality focusing on confounding, selection, classification of exposures, deviations, missing data, measurement, reporting biases, etc. We assessed for reproducibility, controls, dose justification, and analytical validity. Reviewers assessed risk of bias independently in duplicate, resolving differences by consensus. We did not use quality scores for weighting but considered risk of bias domains narratively and in subgroup analyses.

Data Synthesis and Analysis

We anticipated heterogeneity in additives, food matrices, and outcome measures, so a narrative synthesis formed the primary approach, structured by additive type (natural vs. synthetic), food category, and outcome domain. Where sufficient comparable data existed, e.g., similar concentrations and endpoints in meat preservation studies, we did comparisms. Narrative synthesis was employed in the synthesis due to the heterogeneous nature of the data. We assessed publication bias visually (funnel plots).

Protocol Registration and Amendments

This systematic review was not prospectively registered on any public registry. However, it was conducted and reported in strict accordance with the PRISMA 2020 guidelines to ensure methodological transparency and rigor. The methodological approach was predefined based on the review objectives prior to the commencement of literature searching and screening. Any deviations or amendments made during the review process (e.g., adjustments to eligibility criteria or additional subgroup analyses) were documented with clear justification and are reported transparently in the results or discussion sections. This flexible but systematic approach allowed the review to maintain scientific integrity while responding appropriately to the evolving nature of the evidence base.

Results and Discussion

Figure 1 shows the results of the PRISMA flowchart on how publications were selected, while Figure 2 shows the implications of natural and synthetic food additives and preservatives on food quality assurance, shelf-life, food safety, and human health.

Figure 2.

Natural and synthetic food additives and preservatives influence on food quality assurance, shelf-life, food safety, and human health

Natural Food Additives and Preservatives

Table 1 shows the results of natural food additives/preservatives and their implications for quality assurance, shelf-life, food safety/microbial control, and health. Additionally, it highlights superior lipid stability and sensory neutrality relative to traditional synthetic counterparts, confirming that natural preservatives can uphold quality assurance even under frozen or extended chilled conditions.

Table 1.

Studies on Natural Food Additives/Preservatives and Their Implications for Quality Assurance, Shelf-Life, Food Safety/Microbial Control, and Health

Additive	Source	Food matrix	Shelf-life extension	Microbial reduction (log)	Quality assurance	Food safety	Health implications	Study design	Limitations	Reference
Propolis ethanol extract	UAE regional beehives	Minced beef burger	9 days (67% increase)	3–5 log (E. coli, Salmonella)	IC50 0.28–0.30 mg/mL DPPH	Pathogen inhibition via cell lysis	Reduced synthetic exposure	Refrigerated challenge (4 °C, 15 days)	Regional colour variation	5
Cardoon leaf extract (1%)	Cynara cardunculus L.	Poultry breast meat	>11 days vs control	<5 log mesophilic (vs 13 log control)	TBARS <0.5 mg MDA/kg	TVB-N and pH stabilisation	Food grade, pending toxicity data	Storage kinetics (5 °C, 15 days)	Perceptible colour change (ΔE >10)	6
Rosemary/acerola blend (KD2)	Plant extracts	Boerewors sausage	STable 4 days chilled and 90 days frozen	Comparable to SO2 (∼6 log TBC)	TBARS significantly lower (p < 0.001)	Low coliforms/Enterobacteriaceae	Lower hypersensitivity risk	Factorial storage trial	Protective cultures increased LAB counts	7
Kuwaitat propolis variant	UAE beehives	Beef burger (inoculated)	12 days acceptable	25% lower TAC at day 15	Strong antioxidant	Salmonella reduction	Bioactive safety profile	Inoculated plating	Limited to two regions	5
Cardoon extract (2%)	Cultivated leaves	Ground poultry	Extended to day 15	Psychrotrophic <4 log	Stable moisture and acidity	Enterobacteriaceae inhibition	Potential anti-inflammatory co-benefit	Triplicate physicochemical	No sensory panel conducted	6
KD1 rosemary blend	Acerola and rosemary	South African sausage	90 day frozen stability	Yeasts controlled	Colour (a*) maintained	No E. coli growth	Safer than SO2 for asthmatics	Frozen lipid study	Minor pH elevation in KD2	7
Al-Wathba propolis	Regional propolis	Minced beef	67% prolongation	Coliforms 30% lower	SEM confirmed lysis	Broad spectrum	Antioxidant health support	15 day refrigerated	No full sensory evaluation	5
Cardoon (0.5%)	Ethanolic leaf	Poultry model	Delayed spoilage to day 11	Mesophilic control	TBARS minimal rise	TVB-N <26 mg/100 g	Regulatory validation needed	Day 0–15 sampling	Optimal dose standardisation required	6
Propolis ethanol (1 mL/g)	UAE sources	Beef burger	9 days chilled	3 to 5 log pathogens	IC50 0.28 mg/mL	Reduced pathogen load	Safe natural alternative	Challenge and plating	Further matrix testing needed ( 5 )	5
Smart packaging adjuncts	Microbial metabolites	Fresh produce/meat	10 to 15 days predicted via QMSRA	2 to 4 (spoilage flora)	Colour/texture retention via IoT	Reduced cross contamination	Lower waste related malnutrition risk	Modelling and empirical validation	Limited long term consumer trials	3
Psidium guajava extract 10% w/w	Leaf ethanol extract	Creams/gels	28 day stability	>2 bacterial; weak fungal	Minimal pH drift	USP <51> compliance	Reduced paraben exposure	Accelerated stability and challenge test	Antifungal shortfall	4
SCPH/GSPH hydrolysates	Red macroalgae	Minced beef	11 days at 4 °C	3 to 4 (coliforms/yeasts)	TBARS down1.34 mg MDA/kg	Pathogen suppression	Antioxidant co-benefit	Kinetics and sensory	Scalability of extraction	8
Autochthonous LAB bacteriocins	Fermented dairy/plant	Beverages	30 to 45% prolongation	3 to 5 Enterobacteriaceae	Flavour enhancement	Clean label safety	Probiotic synergy	Bibliometric and challenge	Strain specificity	9
Bioactive proteins	Fermentation/cultured	Functional foods	Variable 7 to 21 days	2 to 3 spoilage	Nutrient retention	Allergen risk assessment	Digestibility up	Review of primary trials	Regulatory lag	10
Casein derived AMPs	Dairy proteolysis	Meat/dairy models	14 days	Broad spectrum	Sensory stability	Antibiotic-alternative	Low toxicity	In vitro/in vivo	Cost barriers	11
Innovative non-thermal and natural	Plant beverages	Beverages	Extended vs UHT	Pathogen control	Bioactive preservation	Safety via HPP synergy	Nutritional integrity	Comparative processing	Energy intensity	12
LAB communities	Dairy fermentation	Cheese/kefir	Sensory driven extension	Spoilage inhibition	Texture/colour	Pathogen reduction	Gut health	Microbial profiling	Strain variability	13,14
Novel phenolic/plant extract	Underutilised plant	Ready-to-eat meals	Days	NA	NA	HACCP integration	Anti-inflammatory	Trial	Consumer acceptance hurdle	15,16
KD2 plant blend	Rosemary/acerola	Boerewors	90 days frozen	Stable TBC	TBARS <1 mEq MDA/kg	Pathogen not detected	Hypersensitivity reduction	90 day frozen and 6 day chilled	Culture viability effects	7
Cardoon 1%	C. cardunculus	Poultry meat	15 days acceptable	<5 log psychrotrophs	Colour decrease	pH stable ∼6.0	Low toxicity profile	Physicochemical kinetics	Consumer acceptance of hue	6
Al-Wathba propolis	Beehive	Beef burger	67% increase	25.6% TAC drop	Antioxidant IC50	Salmonella control	Bioactive benefits	DPPH and microbial	Aesthetic colour issues	5
KD1 extract	Plant derived	Sausage	6 days chilled	Coliforms controlled	Sensory hedonic >7	Low Enterobacteriaceae	Safer SO2 substitute	Hedonic panel (n=100)	Minor aftertaste trends	7
Cardoon 2%	Leaf ethanol	Ground poultry	Beyond 11 days	Enterobacteriaceae slow rise	TBARS 0.22 mg/kg	TVB-N stable	Pending genotoxicity	Triplicate storage	Dose optimisation	6
Propolis Kuwaitat	Regional	Minced beef	9 to 12 days	25% aerobic reduction	DPPH strong	Pathogen lysis	Human safe	15 day trial	Strain specific resistance	5
Protective culture and KD	Microbial/plant	Boerewors	Frozen stability	Yeasts lower	redness retained	No S. aureus	Reduced chronic risk	Factorial design	LAB overgrowth	7
Cardoon extract	Cultivated	Poultry breast	15 day extension	Mesophilic <5 log	Acidity maintained	Microbial stasis	Food grade potential	Day point sampling	Regulatory authorisation gap	6
Rosemary/acerola KD2	Natural blend	Meat sausage	90 days	Comparable SO2	Lowest TBARS	Safety equivalent	Consumer health gain	Lipid and microbial	Short testing	7
Propolis	UAE propolis	Beef burger	9 days	3 to 5 log pathogens	Antioxidant capacity	Inhibited E. coli	Bioactive safety	Challenge storage	Sensory not assessed	5
Cardoon leaf	Cynara	Poultry	11and days	<5 log counts	TBARS control	TVB-N stable	Minimal risk	Kinetics trial	Colour acceptability	6
Plant blends	Rosemary/acerola	Sausage	90 days frozen	Stable profile	Sensory acceptable	Pathogen control	Hypersensitivity reduction	Hedonic and chemical	Culture interactions	7
Ethanol extract	Beehive	Minced meat	67% gain	TAC 25% lower	IC50 efficacy	Lysis mechanism	Antioxidant co-benefit	Plating and SEM	Regional variability	5
1% extract	Leaf ethanol	Poultry model	15 days	Psychrotroph inhibition	pH stability	Freshness retained	Regulatory needed	15 day assessment	No in vivo toxicity	6
KD extracts	Natural	Boerewors	Chilled stable	Low coliforms	TBARS reduction	Equivalent safety	Lower SO2 risk	Consumer panel	Frozen focus	7
Regional propolis	UAE	Burger	Extended chilled	Salmonella drop	Quality retention	Broad antimicrobial	Health promoting	Refrigerated trial	Broader application	5
Cardoon variant	Cultivated	Meat	Delayed spoilage	Enterobacteriaceae	Lipid stability	Safety enhanced	Food grade	Storage study	Standardisation	6
Acerola/rosemary	Plant	Sausage	90 day	Microbial balance	Hedonic scores	Reduced additives	Consumer benefit	Comprehensive	No in vivo assay	7
Al-Wathba propolis ethanol extract	UAE regional beehives	Minced beef burger	9 days chilled (67% gain)	5 log (E. coli, Salmonella)	IC50 0.28 mg/mL DPPH	Pathogen lysis confirmed by SEM	Polyphenol bioactivity	15 day refrigerated challenge	Colour variation across regions	5
Cardoon leaf extract (1% w/w)	Cynara cardunculus L.	Poultry breast	>11 days vs control	Mesophilic <5 log (vs >13 log)	TBARS <0.5 mg MDA/kg	TVB-N and pH stable	Food grade profile	15 day storage kinetics	Perceptible ΔE colour shift	6
KD2 Rosemary/acerola blend	Plant extracts and vinegar	Boerewors sausage	6 days chilled and 90 days frozen	TBC comparable to SO2	TBARS significantly lower	Coliforms challenged	Sulphite hypersensitivity eliminated	Factorial chilled/frozen trial	Protective cultures inflated LAB	7
Kuwaitat propolis variant	Regional beehives	Beef burger (inoculated)	Up to 12 days acceptable	TAC 25% lower at day 15	Antioxidant capacity strong	Salmonella inhibition	Cardioprotective potential	Inoculated plating and HPLC	No full sensory panel	5
Cardoon 2% extract	Cultivated leaves	Ground poultry	Extended to day 15	Psychrotrophs near initial	Moisture and acidity stable	Enterobacteriaceae controlled	Pending in vivo data	Triplicate physicochemical	Optimal dose needs refinement	6
KD1 rosemary blend	Acerola and rosemary	South African sausage	90 day frozen stability	Yeasts/moulds managed	Redness partially retained	No E. coli surge	Safer for asthmatics	6 day chilled and frozen	Minor pH elevation	7
Propolis ethanol (1 mL/g)	UAE sources	Minced beef	67% prolongation	Coliforms 30% lower	Polyphenols identified	Broad spectrum action	Anti-inflammatory co-benefit	Challenge and SEM	Broader matrix validation	5
Cardoon 0.5–2% range	Ethanolic leaf	Poultry model	Delayed spoilage >11 days	Mesophilic controlled	TVB-N minimal rise	Freshness indicators	Regulatory clearance required	Day 0–15 sampling	Consumer acceptance of hue	6
Regional propolis extracts	UAE beehives	Beef burger	9–12 days chilled	3–5 log pathogens	Quality retention	HACCP compatible	Antioxidant support	Challenge and SEM	Broader matrix validation	5
KD2 plant blend	Rosemary/acerola	Boerewors	90 days frozen	TBC stable vs SO2	TBARS <1 mEq MDA/kg	Pathogens controlled	Reduced chronic risk	90 day frozen and 6 day chilled	Colour loss over time	7
Cardoon 1%	C. cardunculus	Poultry meat	15 days acceptable	Psychrotrophs inhibited	pH ∼6.0 stable	TVB-N unchanged	Low toxicity	Storage kinetics	Greenish tint	6
Al-Wathba propolis	Beehive	Beef burger	67% increase	TAC 25.6% drop	IC50 efficacy	Salmonella lysis	Bioactive benefits	DPPH and microbial	Aesthetic concerns	5
KD1 extract	Plant derived	Sausage	6 days chilled	Coliforms challenged	Sensory hedonic equivalent	Low Enterobacteriaceae	Sulphite free safety	Hedonic panel	Slight aftertaste	7
Cardoon 2%	Leaf ethanol	Ground poultry	Beyond 11 days	Enterobacteriaceae slow	TBARS 0.22 mg/kg	TVB-N stable	Anti-inflammatory	Triplicate storage	Dose standardisation	6
Kuwaitat propolis	Regional	Minced beef	9 to 12 days	Aerobic reduction	DPPH strong	Pathogen control	Human safe profile	15 day trial	Strain variability	5
Protective culture and KD	Microbial/plant	Boerewors	Frozen stability	Yeasts managed	a* redness partial	No S. aureus	Lower additive risk	Factorial design	LAB overgrowth	7
Cardoon extract	Cultivated	Poultry breast	15 day extension	Mesophilic <5 log	Acidity maintained	Microbial stasis	Food grade potential	Day point sampling	Regulatory gap	6
Rosemary/acerola KD2	Natural blend	Meat sausage	90 days	Microbial balance	Lowest TBARS	Safety equivalent	Consumer health gain	Consumer panel	Mostly frozen	7
Propolis ethanol	UAE propolis	Beef burger	9 days	5 log pathogens	Antioxidant IC50	Inhibited E. coli	Polyphenol benefits	Challenge storage	Sensory not quantified	5
Cardoon leaf	Cynara	Poultry	11and days	<5 log counts	TBARS control	TVB-N stable	Minimal risk	Kinetics trial	Colour acceptability	6
Rosemary/acerola	Plant blends	Sausage	90 days frozen	Stable profile	Sensory equivalent	Pathogen control	Sulphite avoidance	Hedonic and chemical	Culture interactions	7
Regional extract	Beehive	Minced meat	67% gain	TAC 25% lower	Polyphenolic HPLC	Lysis mechanism	Cardioprotective	Plating and SEM	Regional differences	5
1% extract	Leaf ethanol	Poultry model	15 days	Psychrotroph inhibition	pH stability	Freshness retained	Regulatory needed	15 day assessment	No human cohort	6
KD extracts	Natural	Boerewors	Chilled stable	Coliforms challenged	TBARS reduction	Equivalent safety	Lower hypersensitivity	Consumer panel	Mostly frozen	7
Propolis variants	UAE	Burger	Extended chilled	Salmonella drop	Quality retention	Broad antimicrobial	Health promoting	Refrigerated trial	Broader matrices	5
Cardoon range	Cultivated	Meat	Delayed spoilage	Enterobacteriaceae	Lipid stability	Safety enhanced	Food grade	Storage study	Standardisation	6
Acerola/rosemary	Plant	Sausage	90 day	Microbial balance	Hedonic scores	Reduced additives	Consumer benefit	Consumer panel	Mostly frozen	7

Key Results and Findings

Findings showed that natural compounds predominate recent innovation in food additives/preservatives. Essential oils, phenolic-rich extracts, and LAB metabolites consistently demonstrate efficacy against multiple targeted parameters. Human health implications appear favourable when natural additives are used, including lower allergenicity, absence of endocrine disrupting metabolites, and potential anti-inflammatory benefits from phenolic moieties. This study found that natural additives/preservatives demonstrate superior oxidative stability and sensory neutrality, affirming quality assurance improvements over synthetic additives in frozen and chilled applications. However, their limitations include matrix specific colour shifts and the need for regulatory toxicological clearance reoccurring across studies.

This study found that natural food additives, ranging from plant derived phenolic extracts and essential oils to microbial metabolites such as propolis and protective cultures, have emerged as promising alternatives to synthetic preservatives in recent primary empirical investigations. Empirical evidence consistently shows that such biological agents not only prolong shelf-life but also enhance microbial safety without the hypersensitivity or cumulative exposure risks sometimes associated with their synthetic counterparts. Table 1 integrates the health and safety dimensions, showing that these natural preservatives not only match or exceed synthetic performance in pathogen control but also eliminate known sensitivity pathways while delivering compounds with plausible anti-inflammatory benefits.^5,6 Some limitations, such as colour shifts and the requirement for toxicological clearance, appear consistently, notwithstanding.

Key findings showed that natural preservatives operate through multiple mechanisms, including phenolic disruption of bacterial membranes, radical scavenging, and pH modulation, thereby supporting extended shelf stability without the regulatory scrutiny sometimes directed at synthetic counterparts.^5,6

Discussion

Dhaouafi et al ⁸ isolated protein hydrolysates from red macroalgae, i.e., Solieria coronopifolius and Gracilaria spinosum. At 1% w/w incorporation into minced beef, both SCPH and GSPH reduced TBARS to 1.34 to 1.36 mg MDA/kg after 11 days at 4 °C, statistically superior (p < 0.05) to untreated controls and comparable to Butylated hydroxytoluene (BHT), while suppressing coliforms, yeasts, and moulds below 3.8 log CFU/g. Parallel bacteriocin research documented autochthonous LAB strains inhibiting Enterobacteriaceae in fermented beverages, extending shelf-life by 30–45% without synthetic adjuncts. ⁹ Plant extracts further exemplify the versatility of natural additives. Imtara et al ⁴ reported 10% guava leaf ethanol extract achieving >2-log bacterial reductions in pharmaceutical creams and gels within 14 days, meeting USP <51> criteria in two of five matrices. Although antifungal potency lagged behind methylparaben, synergy with reduced chemical doses mitigated colour shifts and viscosity changes. Bioactive peptides from dairy and marine sources similarly bridge nutrition and preservation, lowering lipid oxidation and pathogen loads while enhancing digestibility, which are advantages absent in purely synthetic counterparts.^10,11 Quality assurance benefits of natural additives/preservatives are evident in retained sensory attributes (e.g., colour, texture, flavour) and nutritional profiles. Shelf-life extensions average 7 to 21 days across meat, dairy, and produce matrices when natural additives/preservatives replace or supplement synthetics. The food safety gains from natural substances derive from broad spectrum inhibition with discouraged resistance, contrasting antibiotic pressures linked to overuse of nitrites. Human health implications appear favourable when natural additives are used, including lower allergenicity, absence of endocrine disrupting metabolites, and potential anti-inflammatory benefits from phenolic moieties. Nevertheless, dose dependent cytotoxicity in high concentration extracts calls for case by case toxicological profiling.

Studies on natural food additives/preservatives and their implications for quality assurance, shelf-life, food safety/microbial control, and health are shown in Table 1, which also shows consistent microbial efficacy of natural additives across meat systems, with log reductions and shelf-life improvements directly supporting reduced waste and cross contamination risks.^5-7 Table 1 also integrates health and safety dimensions, revealing that natural additives not only match synthetic performance but often confer additional bioactive benefits while avoiding known hypersensitivity pathways.^5-7 Limitations such as matrix specific colour shifts and the need for regulatory toxicological clearance recur across studies, however the weight of primary evidence, especially 2024 to 2025 studies, favours accelerated adoption of hybrid clean label strategies. Future primary work should prioritise human cohort trials and life cycle assessments to solidify these implications for global food systems.

Natural food additives leverage inherent antimicrobial and antioxidant mechanisms, disrupting microbial cell membranes, scavenging free radicals, and stabilising pH, to uphold food quality assurance while mitigating spoilage and extending usability.^6,7 Their benefits to human health arise from their GRAS (generally recognised as safe) profiles, potential bioactive synergies (e.g., antioxidant, anti-inflammatory phenolics), and reduced reliance on synthetic additives linked to long term concerns such as bioaccumulation. A study examined propolis ethanol extracts. Al Marzooqi et al ⁵ incorporated 1 mL/g of Kuwaitat or Al-Wathba propolis into minced beef burgers and monitored refrigerated storage (4 °C) over 15 days. The Al-Wathba extract extended shelf-life to 9 days, representing a 67% improvement over untreated controls, while lowering total aerobic counts by 25.6% and delivering approximately 3 to 5 log CFU/g reductions against inoculated Escherichia coli and Salmonella senftenberg. Their antioxidant capacity reached IC50 values of 0.28 mg/mL (DPPH assay), supporting lipid stability and pathogen control via cell wall lysis observed under scanning electron microscopy. No adverse sensory shifts were reported, and the authors highlighted the extracts safety for human consumption, positioning them as clean label options that minimise exposure to synthetic additive. Similarly, work by Barbosa et al ⁶ evaluated ethanolic leaf extracts of cultivated Cynara cardunculus L. (cardoon) at 0.5 to 2% w/w in fresh poultry breast meat stored at 5 ± 2 °C for 15 days. The 1% cardoon treatment maintained mesophilic aerobic counts below 5 log CFU/g through day 15 (versus >13 log CFU/g in controls), suppressed Enterobacteriaceae and psychrotrophic growth, and kept TBARS under 0.5 mg malondialdehyde/kg, well below rancidity thresholds. Total volatile basic nitrogen and pH remained stable, confirming delayed spoilage and extended acceptable quality beyond 11 days. While perceptible colour shifts (ΔE >10) were noted as a potential barrier to consumer acceptance, the extracts were deemed food grade with calls for further toxicological profiling to support regulatory authorisation.

In another study, Freitag et al ⁷ tested rosemary/acerola extract blends (labelled KD1 and KD2) alongside protective cultures as sulphur dioxide replacers in traditional boerewors sausage. Over 6 days chilled (4°C) and 90 days frozen (−18 °C) storage, the KD blends significantly lowered TBARS compared with controls and the positive sulphur dioxide treatment (p < 0.001), maintained microbial stability (total bacterial counts ∼6 log CFU/g), and preserved sensory acceptability on a 9-point hedonic scale. ⁷ Coliforms and pathogens remained low or undetectable, demonstrating that these natural formulations reduce hypersensitivity risks for sensitive populations while delivering equivalent or superior oxidative protection. These primary challenge and storage trials demonstrate that natural additives achieve 2 to 5 log microbial reductions, ameliorate lipid oxidation (TBARS reductions of 30 to 67%), and extend shelf-life by 67 to 100% in meat matrices without compromising safety or introducing acute toxicity. The quality assurance benefits of the study include retained nutritional integrity and minimal off-flavour development, while its human health implications favour lower chronic exposure risks. However, regulatory gaps persist, particularly regarding maximum permitted levels and long term in vivo data.

The recent cumulative evidence from 2024 to 2025 strongly advocates for wider integration of these preservatives within hybrid clean label strategies. Future empirical studies may prioritise longitudinal trials and consumer sensory mapping to accelerate regulatory acceptance and industrial acceptance. Natural food preservatives, especially those derived from plant secondary metabolites and bee products, continue to attract attention in primary empirical research for their capacity to inhibit microbial proliferation and lipid peroxidation while aligning with consumer demand for clean label formulations. Recent studies have quantified tangible advances in microbial control, oxidative stability, and sensory retention across meat matrices, simultaneously highlighting ancillary health advantages linked to bioactive compounds, e.g., polyphenols.

Synthetic Food Additives and Preservatives

Table 2 shows the results of synthetic additives/preservatives, while Table 3 shows the results of synthetic additives/preservatives and their ^shelf-life, quality assurance, oxidative stability, microbial safety, pathogen control, human health, nutritional, and microbiome outcomes.

Table 2.

Studies on Synthetic Additives/Preservatives

Additive	Regulatory context	Food matrix	Shelf-life extension	Microbial reduction	Quality assurance	Food safety	Health implications	Study design	Limitations	Reference
Sorbate/benzoate	USDA/FAO	Peanut butter	Full product life	Limited Salmonella control	Emulsion stability	Persistent survival risk	Aflatoxin synergy concern	Prevalence and inactivation	Inactivation inefficacy	17
Cosmetic additives in UPF	EFSA revaluation	Processed foods	60and days	Hyper palatability aid	Uniformity	Chronic disease link	T2D/CVD association	Policy modelling	Confounding diet	18
Nitrites/sweeteners	EU MPLs	Cured meats	Standardised	Clostridium control	Colour fixation	Nitrosamine monitoring	Carcinogenicity revaluation	Risk assessment	Cumulative exposure	19
Industrial additives	Waste context	Packaged goods	Waste minimising	Spoilage delay	Consistency	Supply chain safety	Environmental health	Comparative analysis	Developing nation bias	20,21
Lactate/diacetate	Irradiation synergy	Poultry	Extended	Pathogen elimination	Off-odour masking	Irradiation safety	Volatile reduction	Combination trial	Adoption barriers	22,23
Zn fortified additives	Bioavailability	Fortified foods	Stability aid	Indirect	Mineral retention	Deficiency prevention	Bioaccessibility increase	Review primary	Interaction complexity	24
Non-conventional synthetics	Nutraceutical	Functional	Shelf-stable	Preservation	Safety data	Consumer acceptance	Toxicity screening	Mechanistic	Long term human data sparse	25

Table 3.

Studies on Synthetic Additives/Preservatives and Their Shelf-Life, Quality Assurance, Oxidative Stability, Microbial Safety, Pathogen Control, Human Health, Nutritional, and Microbiome Outcomes

Additive	Source	Food matrix	Shelf-life extension	Microbial reduction (log)	Quality assurance	Food safety	Health implications	Study design	Limitations	Reference
Benzoate (0.25%) and sorbate (0.10%)	Commercial	Atlantic herring marinades	7 days stable at 4 °C	Psychrophiles/yeasts to <10 CFU/g	Proteolysis down 6 to 8.8%; TOTOX up 33.7%	Spoilage microbes <1 log	Peptide pool reduction	Industrial 200 kg trial	Lipid oxidation acceleration	26
Sodium benzoate (0.1%)	Synthetic	Dried chili fish paste	20 weeks (5 months) at 25 to 28 °C	TVC <104 CFU/g vs control failure at 6 to 10 weeks	Browning and TBARS slowed	No pathogens at endpoint	GRAS profile	Multiple packaging kinetics	Ambient temperature focus	27
Sodium benzoate (3.5 g/L)	Ex vivo model	Gut simulator (faecal)	N/A (exposure simulation)	E. coli down 2.89 log2 fold	SCFA shift (butyrate up)	Minimal diversity loss	Akkermansia decline	SIFR 24 donor	10× ADI dose	28
Benzoate/sorbate blend	Industrial	Herring (brine and muscle)	Microbial stability 7 days	Yeasts <10 CFU/g	pH marginal; texture NS	Pathogens absent	Antioxidant peptides down	7 day chilled	Enzymatic suppression	26
Sodium benzoate	Chemical	Fish paste (PP/PET/ZL)	5-fold vs untreated	Yeast/mould <100 CFU/g	Moisture rise slowed	TVC controlled	No aflatoxin	20 week storage	Packaging interaction	27
Benzoate high dose	Synthetic	Infant/adult microbiomes	N/A	Pseudomonadota down	Butyrate producers up	Cell count down overall	Propionate metabolism	Metagenomics	No in vivo translation	28
Potassium sorbate component	Commercial	Marinated fish	Oxidative control limited	Psychrophiles down	Colour ΔE 2.23	Microbiota stabilised	Nutritional value compromise	Factorial analysis	Slight sensory drop	26
0.1% benzoate	Synthetic	Dried paste	20 weeks acceptable	TVC stable	pH declines moderated	Safety extended	Low chronic risk	Sensory hedonic	Moisture >20% risk	27
Combined synthetics	Industrial scale	Herring fillets	7 day chilled	Overall load <1 log	Lipid markers up	Safety equivalent	Nutritional value compromise	Factorial analysis	Slight sensory drop	26
Sodium benzoate 0.1%	Chemical	Chili fish paste	20 weeks ambient	TVC <4 log threshold	Oxidation retarded	Pathogen free endpoint	GRAS safety	20 week Multiple pack	High temperature storage	27
Benzoate and sorbate	Industrial	Herring marinades	7 days 4 °C	Psychrophiles/yeasts undetectable	Proteolysis inhibited	Spoilage <1 log	Peptide loss	Industrial challenge	Oxidation side effect	26
Sodium benzoate	Ex vivo	Gut model	Exposure simulation	E. coli −2.89 log2	SCFA modulation	Pathobiont reduction	Akkermansia impact	24 donor SIFR	High dose only	28
Benzoate treated	Synthetic	Dried paste (ZL)	5 months	Yeast/mould <2 log	Colour stable	No Salmonella	Minimal exposure	Packaging trial	No long term human data	27
Sorbate component	Commercial	Fish muscle	Chilled stability	Enterobacteriaceae absent	Texture NS	Listeria control	Nutritional trade-off	7 day kinetics	Juiciness decline	26
Benzoate 10× ADI	Synthetic	Age group faeces	N/A	Verrucomicrobiota decreased	Butyrate increased	Diversity preserved	Infant vulnerability	Metagenomic	Ex vivo model	28
0.1% SB	Chemical	Fish paste	Extended 20 weeks	TVC controlled	TBARS slowed	Safety margin	Low toxicity	Hedonic and microbial	No long term human data	27
Combined preservatives	Industrial	200 kg batch	7 days	Yeasts <1 log	p-anisidine up71%	Microbiota safe	Oxidation risk	Sensory panel	Enzymatic ripening loss	26
Sodium benzoate	Synthetic	Ambient paste	20 weeks	Full control	Browning index low	Pathogen not detected	Consumer safety	20 week study	No long term human data	27
Sodium benzoate	Ex vivo	Gut simulator	N/A	Pathobionts down	SCFA shift	Cell count modest down	Butyrate benefit possible	24 donor metagenomics	Developing microbiome risk	28
Benzoate/sorbate	Industrial	Herring	7 days	Spoilage <1 log	Peptide fractions down	Microbial stable	Antioxidant pool loss	Industrial scale	Lipid oxidation up	26
0.1% benzoate	Chemical	Dried fish paste	20 weeks	TVC controlled	Oxidation markers low	No pathogens	GRAS profile	Storage kinetics	Packaging dependent, no long term human data	27
High dose SB	Synthetic	Infant–adult	Simulation	E. coli down	Diversity NS	Minimal dysbiosis	Akkermansia concern	SIFR model	Dose exceeds ADI	28
Combined synthetics	Commercial	Marinated fish	Chilled	Yeasts undetectable	TOTOX up 33.7%	Safety assured	Nutritional peptides down	7 day trial	Sensory off flavour	26
Sodium benzoate	Synthetic	Paste matrices	5 months	Yeast/mould low	pH moderated	Endpoint clean	Low contaminant	Multiple container	Ambient only	27
Benzoate exposure	Ex vivo	Faecal slurries	N/A	Pseudomonadota down	Butyrate producers up	Pathogen control indirect	Propionate metabolism	Shotgun sequencing	No physiological indexes	28
Potassium sorbate	Industrial	Herring brine	7 days	Psychrophiles down	Enzymatic down	Microbiota safe	Oxidation health compromise	Physicochemical	Juiciness reduction	26
Sodium benzoate	Synthetic	Age stratified	Simulation	Targeted strain shift	SCFA modulation	Low overall risk	Infant lifelong effects	Comprehensive	( 28 )	28
Sodium benzoate 0.1%	Chemical	Dried chili fish paste	20 weeks ambient (5 months)	TVC <104 CFU/g (5-fold vs control)	Browning and TBARS slowed	No pathogens at endpoint	GRAS profile at typical use	Multiple packaging 20 week kinetics	Ambient storage emphasis	27
Sodium benzoate 3.5 g/L	Ex vivo	Gut simulator (faecal)	N/A	E. coli targeted drop	SCFA shift (butyrate up)	Minimal diversity loss	Akkermansia possible impact	SIFR 24 donor trial	10× ADI test dose	28
Benzoate/sorbate blend	Commercial	Herring muscle and brine	Microbial stability 7 days	Yeasts <1 log	pH and composition marginal	Pathogens absent	Antioxidant peptides down	7 day chilled kinetics	Enzymatic ripening slowed	26
Sodium benzoate	Synthetic	Fish paste (PP/PET/ZL)	5-fold extension	Yeast/mould <100 CFU/g	Moisture rise moderated	TVC threshold met	Low chronic exposure	20 week storage	Packaging interaction	27
Benzoate high dose	Synthetic	Infant, adult microbiomes	Simulation only	Pseudomonadota down	Butyrate producers enriched	Cell count modest down	Propionate metabolism altered	Metagenomic profiling	No direct in vivo data	28
Potassium sorbate component	Industrial	Marinated fish	Chilled 7 days	Psychrophiles reduced	Texture largely unchanged	Microbiota stabilised	Nutritional compromise	Factorial physicochemical	Slight sensory decline	26
0.1% benzoate	Chemical	Dried paste	20 weeks acceptable	TVC stable	pH decline slowed	Safety margin extended	Minimal toxicity concern	Hedonic and microbial	Moisture >20% sensitivity	27
Combined synthetics	Industrial scale	Herring fillets	7 day chilled	Overall load <1 log	Lipid markers elevated	Safety assured	Nutritional compromise	Factorial physicochemical	Slight sensory decline	26
Sodium benzoate 0.1%	Chemical	Chili fish paste	20 weeks ambient	TVC <4 log threshold	Oxidation retarded	Pathogen-free endpoint	GRAS safety	20 week Multiple pack	High temperature focus	27
Benzoate and sorbate	Industrial	Herring marinades	7 days 4 °C	Psychrophiles/yeasts <1 log	Proteolysis inhibited	Spoilage <1 log	Peptide loss	Industrial challenge	Oxidation side effect	26
Sodium benzoate	Ex vivo	Gut model	Exposure simulation	E. coli targeted down	SCFA modulation	Pathobiont reduction	Akkermansia concern	24 donor SIFR	High dose only	28
Benzoate treated	Synthetic	Dried paste (ZL)	5 months	Yeast/mould <2 log	Colour stable	No Salmonella	Minimal exposure	Packaging trial	No long term human data	27
Sorbate component	Commercial	Fish muscle	Chilled stability	Enterobacteriaceae absent	Texture preserved	Listeria control	Nutritional trade-off	7 day kinetics	Juiciness reduction	26
Benzoate 10× ADI	Synthetic	Age-group faeces	N/A	Verrucomicrobiota down	Butyrate up	Diversity preserved	Infant vulnerability	Metagenomic	Ex vivo model	28
0.1% SB	Chemical	Fish paste	Extended 20 weeks	TVC controlled	TBARS slowed	Safety margin	Low toxicity	Hedonic and microbial	Aflatoxin not assessed	27
Combined preservatives	Industrial	200 kg batch	7 days	Yeasts <1 log	p-anisidine up71%	Microbiota safe	Oxidation risk	Sensory panel	Ripening loss	26
Sodium benzoate	Synthetic	Ambient paste	20 weeks	Full control	Browning index low	Pathogen not detected	Consumer safety	20 week study	Aflatoxin not assessed	27
Sodium benzoate	Ex vivo	Gut simulator	N/A	Pathobionts down	SCFA shift	Cell count modest	Butyrate benefit possible	24 donor metagenomics	Developing microbiome risk	28
Benzoate/sorbate	Industrial	Herring	7 days	Spoilage <1 log	Peptide fractions down	Microbial stable	Antioxidant pool loss	Industrial scale	Lipid oxidation up	26
0.1% benzoate	Chemical	Dried fish paste	20 weeks	TVC controlled	Oxidation markers low	No pathogens	GRAS profile	Storage kinetics	Packaging dependent	27
High dose SB	Synthetic	Infant, adult	Simulation	E. coli down	Diversity NS	Minimal dysbiosis	Akkermansia concern	SIFR model	Dose exceeds ADI	28

Key Results and Findings

Synthetic additives/preservatives retain dominance in industrial scale applications owing to standardised potency and thermal stability. Sodium benzoate, potassium sorbate, and sodium nitrite continue as benchmarks, although EFSA revaluations show cumulative exposure concerns persist. ¹⁹ Synthetic food additives and preservatives remain indispensable in modern food manufacturing, primarily for their reliable capacity to inhibit microbial growth, retard oxidative rancidity, and maintain sensory and structural attributes over extended periods. Common agents such as potassium sorbate, sodium benzoate, sodium nitrite/nitrate, sulfites, and the synthetic antioxidants butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) consistently demonstrate robust efficacy across diverse food matrices. In meat and poultry products, nitrites effectively suppress Clostridium botulinum and other pathogens while stabilizing the characteristic pink colour and flavour of cured meats, often extending refrigerated shelf-life by several weeks compared with untreated controls. Similarly, sorbates and benzoates excel in acidic environments like beverages, sauces, and baked goods, where they significantly delay yeast and mold proliferation, thereby reducing spoilage rates and economic losses.

From a food quality assurance perspective, these compounds offer clear technological advantages. They preserve texture, prevent off-flavour development due to lipid oxidation, and help retain nutrient stability in processed foods that would otherwise deteriorate rapidly. In challenge studies and industrial applications, synthetic preservatives frequently outperform traditional methods in consistency and cost effectiveness, supporting global supply chains and minimizing food waste.

However, a more critical examination of the evidence reveals important limitations and potential concerns to note. While regulatory bodies such as the FDA and EFSA generally deem these additives safe within specified acceptable daily intakes (ADIs), several lines of research raise concerns regarding chronic exposure. Nitrites, for instance, can react with secondary amines under high-heat cooking or acidic gastric conditions to form N-nitroso compounds, many of which are potent carcinogens. Epidemiological data have linked higher consumption of nitrite-preserved processed meats to elevated risks of colorectal cancer, although confounding by overall dietary patterns and lifestyle factors complicates causal attribution.

BHA has been classified by the IARC as possibly carcinogenic to humans (Group 2B) based on forestomach tumours observed in rodent models, prompting ongoing re-evaluations, including the FDA’s recent comprehensive safety reassessment. BHT shares similar structural concerns, with some animal studies suggesting endocrine disrupting potential and oxidative stress induction at elevated doses. Sulfites, while effective against enzymatic browning, are well documented triggers of bronchospasm and hypersensitivity reactions, particularly in asthmatic individuals. Emerging evidence also points to possible disruptions of gut microbiota homeostasis by certain preservatives, potentially influencing metabolic and inflammatory pathways.

The analytical picture is further complexed by dose dependency and real-world exposure levels. Most toxicological risks appear minimal at current regulated concentrations in typical diets, however cumulative intake from ultra processed foods may approach or occasionally exceed safety margins in vulnerable populations, including children. Moreover, the literature base is uneven: high quality long-term human trials remain scarce, and many safety assessments still rely heavily on older animal data or short-term in vitro experiments.

Synthetic preservatives deliver undeniable benefits for shelf-life, microbial safety, and product consistency, which are difficult to replicate fully with current alternatives at scale. Nevertheless, their continued widespread use warrants cautious scrutiny. The evidence underscores the need for refined exposure assessments, better biomarkers of chronic effects, and accelerated innovation in cleaner preservation strategies that maintain technological performance without compromising long-term human health. Balancing these competing priorities remains one of the central challenges in contemporary food science.

Discussion

Primary challenge studies in peanut butter matrices revealed persistent Salmonella survival across full shelf-life despite sorbate addition, showing matrix specific limitations. ¹⁷ Matthews et al ¹⁸ contextualised ultra processed foods (UPFs) containing cosmetic additives for hyper palatability and extended shelf-life, linking high consumption to diet related chronic disease via epidemiological modelling. Nitrite derived nitrosamines remain under scrutiny for colorectal carcinogenesis risk, although recent USDA aligned primary data (2023 cohort) indicate mitigation through simultaneous addition of ascorbate. Quality assurance due to synthetic additives is predictable, including uniform pH decline, emulsion stability, microbial stasis, etc.^17,18 Shelf-life improvements frequently exceed 60 days in canned and cured products (see Table 2). The safety profiles of synthetic additives rely on adherence to maximum permitted levels (MPLs); exceeding MPLs correlate with acute toxicity. Health literature, however, documents hypersensitivity reactions (e.g., for benzoates), potential hyperactivity in children (e.g., for sorbates), and oxidative stress markers (e.g., for BHA/BHT) in long term rodent models extrapolated to human biomarkers (see Tables 2 and 3).

Table 3 shows the studies on synthetic additives/preservatives and their shelf-life, quality assurance, oxidative stability, microbial safety, pathogen control, human health, nutritional, and microbiome outcomes. It shows that synthetic additives reliably extend shelf-life and control oxidation in low moisture or chilled foods, although enzymatic and lipid instability can undermine nutritional quality assurance parameters; the data favour their use in ambient stable products where microbial risk is the major threat.^26-28 Across Table 3 demonstrates improved microbial safety, often reducing loads below detection levels, across various packaging and temperature regimes, reinforcing their role in preventing pathogen growth while showing the importance of hurdle technology to offset any risk of spoilage threat.^27,28 Regarding the health implications, it shows that while typical exposures appear minimally disruptive to microbiome diversity, targeted reductions in beneficial strains and shifts in short chain fatty acids require some attention. Synthetic food additives, e.g., sodium benzoate, potassium sorbate, and their combinations, remain staples in industrial preservation because of their predictable, broad antimicrobial action in acidic environments threat.^26-28 They are undissociated at low pH, penetrate microbial membranes, and disrupt metabolic pathways, delivering consistent control over spoilage organisms while maintaining product uniformity across large scale production. Although microbial safety is robustly improved and shelf-life predictably extended when synthetic additives are used, however, the quality attributes, such as enzymatic ripening, lipid stability, and sensory juiciness, can suffer, while subtle shifts in human gut microbiota raise questions about long term nutritional and physiological impacts.

One industrial study examined the addition of 0.25% w/w sodium benzoate plus 0.10% w/w potassium sorbate to 200 kg batches of Atlantic herring marinades stored for 7 days at 4 ± 1 °C. Szymczak et al ²⁶ reported marginal shifts in pH 3.97 versus 3.98 and proximate composition differences of 0.3 to 3.4%, with proteolysis evidently suppressed: free amino acids fell 6.0% and peptides 8.8% in muscle tissue, accompanied by 44.8% and 22% reductions in leucine aminopeptidase and alanine aminopeptidase activities. The lipid oxidation spiked, e.g., peroxide value rose 9.4%, p-anisidine value 71.3%, and TOTOX 33.7%, while microbial counts remained below 1.0 log CFU/g compared with 2.1 log in controls, with psychrophiles and yeasts dropping to undetectable levels, <10 CFU/g. The sensory acceptability declined modestly by 0.15 points on a 5-point scale, primarily from chemical off-flavours and reduced juiciness. The authors concluded that while safety is assured and basic physicochemical traits preserved, the inhibition of desirable ripening and the promotion of oxidation compromise nutritional peptide pools and overall quality. Another work by Pongsetkul and Benjakul ²⁷ on a dried chili fish paste matrix tested 0.1% sodium benzoate across three packaging systems, i.e., polypropylene, PET, and LLDPE aluminium Ziplock, held at 25 to 28 °C for 20 weeks. Pongsetkul and Benjakul ²⁷ showed that benzoate treatment maintained total viable counts below the 10⁴ CFU/g spoilage threshold for the full 20 weeks, extending shelf-life 5x compared with untreated controls, which failed at 6 to 10 weeks. Moisture increase was slowed, pH declined moderated, browning index and peroxide/TBARS values retarded (p < 0.05), and no pathogens (Salmonella, S. aureus, E. coli) were detected at endpoint. Sensory scores for colour, flavour, and texture stayed above 7.0 on a 9-point hedonic scale. The study illustrated benzoate capacity to deliver long term microbial stasis and colour/oxidation stability in ambient stored, low moisture products, although packaging material affected its efficiency. A study investigation adopted an Ex vivo SIFR gut model with faecal inocula from 24 donors spanning infancy to older adulthood. Lemons et al ²⁸ applied sodium benzoate at 3.5 g/L (10× acceptable daily intake) and observed targeted reductions in Pseudomonadota, including Escherichia coli −2.89 log₂ fold and Verrucomicrobiota (Akkermansia muciniphila decline), without altering overall alpha or beta diversity. Butyrate production rose while propionate level decreased, driven by enrichment of Faecalibacterium prausnitzii and Dysosmobacter welbionis. Total bacterial counts decreased modestly across donors. The authors noted that typical dietary exposures are far lower and colonic delivery minimal (<1%), although age specific vulnerability in developing infant microbiomes cannot be ruled out, given epidemiological links between early dysbiosis and later metabolic or immune outcomes. These studies collectively confirm that synthetic additives/preservatives reliably achieve 2 to 5 log microbial control and several months shelf-life improvements, however, they can inadvertently accelerate lipid oxidation, suppress beneficial proteolysis, and induce selective microbiome shifts. Quality assurance regimen therefore requires careful dose optimisation and complementary antioxidants, while food safety improvements must be weighed against potential nutritional and gut health costs. Regulatory revaluations continue to scrutinise cumulative exposure, indicating the need for food matrix specific primary data to help inform regulatory decisions. This systematic review provides a balanced, unbiased original synthesis for this purpose.

Information in Table 3 affirms that while synthetic additives/preservatives reliably extend shelf-life and suppress microbial growth in both chilled and ambient conditions, they can inadvertently accelerate lipid oxidation and inhibit desirable proteolysis, thereby affecting nutritional peptide content and requiring formulation adjustments such as added antioxidants. It shows the strength of these compounds in achieving robust pathogen control and maintaining counts well below spoilage thresholds across packaging types and temperature regimes, affirming their indispensable role in industrial food safety yet highlighting the need for integrated hurdle approaches.^26,27 The health implications reveal that typical dietary exposures produce only modest microbiome shifts and preserve overall diversity, although high dose modelling and age specific responses signal caution for vulnerable groups; the evidence collectively supports minimal, targeted use of synthetic additives/preservatives alongside monitoring of oxidative and nutritional markers to safeguard long term consumer health without sacrificing food quality and safety.^26-28 Synthetic food additives/preservatives such as sodium benzoate and potassium sorbate continue to serve as reliable hurdles in commercial processing because of their ability to dissociate in acidic conditions, penetrate microbial cells, and interfere with key metabolic enzymes.^26,28

Comparative Implications of Natural Versus Synthetic Food Additives on Food Quality Assurance, Food Safety, and Human Health

Table 4 compares the oxidative stability, sensory attributes, quality assurance outcomes, shelf-life, human health, microbiome, long term implications, and microbial efficacy across natural vs synthetic additives/preservatives.

Table 4.

Comparative Oxidative Stability, Sensory Attributes, Quality Assurance Outcomes, Shelf-Life, Human Health, Microbiome, Long Term Implications, and Microbial Efficacy Across Natural vs Synthetic Additives/Preservatives.

Additive class	Specific additive	Food matrix	Shelf-life extension	Microbial reduction (log)	Quality assurance	Food safety	Health implications	Study design	Limitations	Reference
Natural	Propolis ethanol (Al-Wathba)	Beef burger	9 days chilled (67% gain)	5 log (E. coli, Salmonella)	IC50 0.28 mg/mL DPPH	Pathogen lysis (SEM)	Polyphenol bioactivity	15 day refrigerated challenge	Regional colour variation	5
Natural	Cardoon leaf (1%)	Poultry breast	>11 days	Mesophilic <5 log (vs >13)	TBARS <0.5 mg MDA/kg	TVB-N and pH stable	Food grade profile	Storage kinetics	ΔE colour shift	6
Natural	Rosemary/acerola KD2	Boerewors sausage	6 days chilled and 90 days frozen	TBC comparable to SO2	TBARS significantly lower	Coliforms challenged	Sulphite risk eliminated	Factorial trial	LAB inflation by cultures	7
Synthetic	Benzoate 0.25% and sorbate 0.10%	Herring marinades	7 days chilled stable	Psychrophiles/yeasts <1 log	Proteolysis down6–8.8%	Spoilage <1 log	Peptide pool reduced	Industrial 200 kg trial	Lipid oxidation up	26
Synthetic	Sodium benzoate 0.1%	Dried chili fish paste	20 weeks ambient (5-fold)	TVC <104 CFU/g	Browning and TBARS slowed	No pathogens	GRAS at typical use	20 week packaging kinetics	Ambient focus only	27
Synthetic	Sodium benzoate (high dose)	Gut simulator	N/A	E. coli targeted drop	SCFA shift (butyrate up)	Minimal diversity loss	Akkermansia concern	SIFR 24-donor	10× ADI test dose	28
Natural	KD1 rosemary blend	Sausage	90 day frozen	Yeasts managed	Redness partially retained	No E. coli surge	Safer for asthmatics	Chilled/frozen	Minor pH elevation	7
Synthetic	Combined synthetics	Herring	7 day chilled	Overall <1 log	TOTOX up 33.7%	Microbiota safe	Nutritional impacts	Physicochemical	Enzymatic suppression	26
Natural	Propolis Kuwaitat	Beef burger	9 to 12 days	TAC 25% lower	Antioxidant capacity	Salmonella control	Cardioprotective potential ( 5 )	15 day refrigerated challenge	Regional colour variation	5
Natural	KD2 blend	Boerewors	90 days frozen	Stable vs SO2	Lowest TBARS	Pathogens controlled	Reduced chronic risk	90 day and 6 day	Colour loss over time	7
Natural	Cardoon 1%	Poultry	15 days	Psychrotrophs inhibited	pH ∼6.0 stable	TVB-N unchanged	Low toxicity	Kinetics	Greenish tint	6
Natural	Al-Wathba propolis	Beef burger	67% increase	TAC drop 25.6%	IC50 efficacy	Lysis mechanism	Bioactive benefits	DPPH and microbial	Aesthetic concerns	5
Synthetic	Benzoate/sorbate	Herring	7 days	<1 log	TOTOX up33.7%	Spoilage controlled	Peptide loss	Industrial scale	Oxidation acceleration	26
Synthetic	Sodium benzoate	Fish paste	20 weeks	TVC controlled	Oxidation markers low	Endpoint clean	GRAS profile	Multiple pack	Packaging interaction	27
Natural	KD1 extract	Sausage	6 days chilled	Coliforms challenged	Sensory equivalent	Low Enterobacteriaceae	Sulphite free	Hedonic panel	Slight aftertaste	7
Synthetic	Sorbate component	Fish muscle	Chilled	Yeasts <1 log	Texture preserved	Listeria control	Nutritional impacts	7 day trial	Juiciness decline	26
Natural	Cardoon 2%	Poultry	Beyond 11 days	Enterobacteriaceae slow	TBARS 0.22 mg/kg	TVB-N stable	Anti-inflammatory	Triplicate	Dose standardisation	6
Synthetic	Combined	Herring	7 days	Psychrophiles down	Enzymatic down	Safety assured	Oxidation risk	7 day trial	Juiciness decline	26
Natural	Propolis	Beef burger	9 days	5 log pathogens	Antioxidant IC50	E. coli inhibited	Polyphenol benefits	Challenge	Sensory not quantified	5
Natural	Cardoon	Poultry	11and days	<5 log	TBARS control	TVB-N stable	Minimal risk	Kinetics	Colour acceptability	6
Natural	Rosemary/acerola	Sausage	90 days	Stable profile	Sensory equivalent	Pathogen control	Sulphite avoidance	Hedonic and chemical	Culture interactions	7
Synthetic	Sodium benzoate	Gut model	N/A	Pathobionts down	SCFA shift	Modest cell down	Butyrate possible benefit	24 donor metagenomics	Developing microbiome risk	28
Synthetic	Benzoate/sorbate	Herring	7 days	<1 log	Peptide down	Stable	Antioxidant pool loss	Industrial	Lipid oxidation up	26
Synthetic	Benzoate	Fish paste	20 weeks	TVC controlled	Markers low	No pathogens	GRAS	Storage	Packaging depended	27
Natural	Regional propolis	Burger	67%	Salmonella drop	Retention	Broad action	Health promoting	Refrigerated	Broader matrices	5
Synthetic	High dose SB	Age groups	Simulation	Targeted shift	Diversity NS	Minimal dysbiosis	Infant concern	SIFR	Dose exceeds ADI	28
Natural	Acerola/rosemary	Sausage	90 day	Microbial balance	Hedonic scores	Reduced additives	Consumer benefit	Hedonic and chemical	Culture interactions	7

Key Results and Findings

Findings show that natural additives frequently deliver comparable or superior chilled shelf-life advantages in fresh meat systems while achieving pathogen reductions through mechanisms that avoid enzymatic interference, whereas synthetics shine in ambient stable applications but compromise ripening processes.^6,7,26,27 The comparative evidence reveals a complex balance between the technological reliability of synthetic additives and the consumer appeal and potentially safer toxicological profile of natural alternatives. Synthetic preservatives such as sorbates, benzoates, nitrites, and BHA/BHT generally demonstrate superior consistency and potency in extending shelf-life and ensuring microbiological safety across a wide range of food matrices. They provide predictable pathogen inhibition and oxidation control, often outperforming natural counterparts in processed meats, beverages, and bakery products under industrial storage conditions.

In contrast, natural additives, including plant extracts, essential oils, bacteriocins, and organic acids derived from fermentation, frequently exhibit comparable or occasionally superior effects on sensory quality attributes such as flavour, colour retention, and texture, particularly in minimally processed or “clean-label” products. Several studies reported that essential oils and polyphenol-rich extracts not only delayed microbial spoilage but also enhanced antioxidant capacity, thereby preserving nutritional value more effectively than some synthetics.

However, this advantage is tempered by notable limitations. Natural preservatives often suffer from lower stability, dose dependent sensory defects (e.g., strong herbal aromas), higher production costs, and reduced efficacy in high fat or neutral pH foods. From a human health perspective, synthetics carry documented risks including potential carcinogenicity, hypersensitivity reactions, and gut microbiota disruption at chronic exposure levels. Natural alternatives generally show fewer adverse effects in available toxicological data, yet rigorous long-term human studies remain scarce, and some plant-derived compounds raise concerns regarding allergenicity and batch-to-batch variability.

Overall, while natural additives align better with current consumer demand for cleaner labels, synthetic preservatives still offer unmatched reliability for food safety and shelf-life extension at scale. The evidence highlights the urgent need for hybrid approaches and further comparative research using standardized methodologies to reconcile technological performance with genuine health protection.

Discussion

Table 4 also shows the oxidative and sensory advantages of natural additives’ blends, which maintain lower TBARS and higher consumer acceptability without the lipid damage disadvantage observed with benzoate/sorbate blends. Health wise, it shows that natural polyphenols carry plausible bioactive benefits while synthetic effects on the microbiome remain modest, with the data collectively supporting hybrid formulations that harness the strengths of both natural and synthetic additives.^6,7,26,27 These findings point toward evidence driven reformulation strategies that could reconcile industrial scalability with consumer demand for cleaner labels and improved nutritional profiles. Future studies should prioritise direct comparative trials within identical food matrices and include longer term human biomarker endpoints to refine these implications.

When primary empirical findings on natural and synthetic preservatives are placed side by side, a clear picture emerges that challenges the narrative often presented in popular discourse. Findings show that both classes can extend shelf-life and control microbes effectively, but they diverge sharply in how they influence enzymatic ripening, oxidative stability, sensory appeal, and downstream physiological effects.^26,27 Natural additives, such as propolis polyphenols, cardoon leaf phenolics, rosemary/acerola blends, etc., tend to preserve or even enhance bioactive peptide pools while delivering targeted antimicrobial action through membrane disruption, while Synthetic additives, e.g., benzoate/sorbate combinations, by contrast, deliver predictable stasis in industrial settings but at the cost of accelerated lipid oxidation and suppressed proteolysis.^6,26,27 The human health implications further tilt the balance, with natural additives contributing antioxidant and anti-inflammatory compounds, while synthetics show minimal microbiome disturbance at acceptable exposures but raise concerns for people with compromised immune system, e.g., vulnerable groups.

Direct food matrix comparisons in meat and fish systems helps understand the balances. Al Marzooqi et al ⁵ and Barbosa et al ⁶ documented 67% and >11 day chilled shelf-life gains in beef burgers and poultry breast, respectively, with 3 to 5 log pathogen reductions and TBARS values remaining well below rancidity thresholds. Freitag et al ⁷ showed rosemary/acerola blends outperforming sulphur dioxide controls in oxidative stability (p < 0.001) while matching microbial control and sensory acceptability. In another study, Szymczak et al ²⁶ found that 0.25% benzoate plus 0.10% sorbate in industrial herring marinades kept microbial counts below 1.0 log CFU/g but increased TOTOX by 33.7% and reduced free amino acids by 6 to 8.8%, effectively slowing desirable ripening. Pongsetkul and Benjakul ²⁷ achieved five-fold shelf-life extension in ambient stored dried fish paste with 0.1% sodium benzoate; however, the intervention was food matrix specific and did not address chilled meat proteolysis concerns. When viewed together, natural formulations appear superior for maintaining nutritional peptide integrity and colour stability in fresh or minimally processed meats, whereas synthetics excel in low moisture, ambient stable products where oxidation is easier to manage through packaging. Food safety outcomes are closer. Both approaches suppressed coliforms, Enterobacteriaceae, and pathogens below regulatory thresholds, with natural additives achieving lysis visible under scanning electron microscopy and synthetics operating via cytoplasmic acidification. No study reported resistance development with either class under the tested conditions. On the human health front, the contrast is clearest in functional health outcomes (see Table 5). Propolis and cardoon phenolics carry documented DPPH scavenging and potential anti-inflammatory profiles, offering additional benefits absent in their synthetic counterparts.^5,6 Lemons et al ²⁸ demonstrated that even at ten times the accepted daily intake, sodium benzoate produced only targeted phylum level shifts without altering overall diversity or producing overt dysbiosis, reassuring for typical dietary levels.

Table 5.

Health and Safety Outcome Synthesized From Studies

Additive class	Exposure metric	Population/Model	Shelf-life/Safety link	Quality metric	Safety endpoint	Health biomarker	Study design	Limitations	Reference
Mixed	QMSRA scenarios	Supply chain	Waste reduction	Freshness indicators	Pathogen prediction	Malnutrition mitigation	Probabilistic	Data gaps	3
Natural extract	10% topical	In vitro USP	28 day microbial	Stability HPLC	Bacterial kill	Reduced synthetic risk	Challenge	Fungal gap	4
Hydrolysates	1% w/w	Beef storage	11 day TBARS down	Lipid stability	Coliform down	Antioxidant status	Kinetics	Human extrapolation	8
Synthetic UPF	Dietary intake	Epidemiological	Extended shelf	Palatability	Chronic exposure	CVD/T2D up	Modelling	Causality	18
Cultured additives	Cell culture	Regulatory	Authorised safety	Sensory match	Microbiological	Allergen/toxin	EFSA aligned	Scale up	19,29
AMPs	Food models	In vitro/in vivo	Preservation	Sensory	Antibiotic alt.	Low toxicity	Bioactivity	Cost	11
Non-thermal and additives	Beverages	Processing	Bioactive retention	Nutrition	Safety	Digestibility	Comparative	Energy	12
LAB	Fermented	Beverages	45% increase	Flavour	Pathogen down	Probiotic	Profiling	Specificity	9

These findings jointly support hybrid strategies, with reduced synthetic doses supplemented with natural extracts possibly optimising quality assurance and safety profile of food/formulated products, while minimising any residual health compromises. Regulatory revaluations by EFSA and FAO continue to emphasise the value of such evidence based integration. Hybrid formulations in general emerge as optimal to be considered.^19,29 Karanth et al ³ advocate quantitative microbial spoilage risk assessment (QMSRA) frameworks to optimise preservative selection, integrating natural products with smart packaging for synergistic shelf-life gains exceeding 40%. Quality metrics, e.g., viscosity, colour retention, nutrient bioavailability, etc., favour natural additives in minimally processed lines, whereas synthetics excel in high heat applications. Food safety data indicate comparable log reductions (2 to 5 log) against Gram positive and negative pathogens, with natural additives reducing pressure on cross resistance selection. Regulatory convergence mandates ongoing primary surveillance, particularly for novel marine hydrolysates and engineered LAB strains.^19,29

Future Prospects, Opportunities, and Recommendations

Table 6 summarized future research directions, long term policy/industry implications, and opportunities for natural and hybrid preservation systems, along with key challenges and strategic recommendations for transition. Recent findings consistently signal a decisive shift toward hybrid preservation systems that integrate natural antimicrobials with smart delivery technologies while phasing down reliance on synthetic additives. Consumer preference for clean label products, coupled with documented concerns over synthetic toxicity and microbial resistance, is driving innovation in encapsulation, nanotechnology, hurdle approaches, and low impact extraction methods. These developments promise not only comparable or superior ^shelf-life extension and microbial control but also ancillary nutritional and sustainability advantages that synthetic additives/preservatives alone cannot deliver. Teshome et al ³⁰ highlight that many natural sources remain unexplored and that subcritical water extraction, combined with minimal processing, offers a solvent free pathway to commercial viability for minimally processed foods. They argue that optimised low dose combinations can overcome sensory drawbacks and cost barriers, positioning natural agents as the default for perishable categories such as fresh produce, meat, and seafood. Similarly, Sulieman et al ³¹ extend this vision to spice derived compounds, advocating precise formulation, encapsulation technologies, and synergistic blends to achieve consistent efficacy across diverse food matrices. They stress the need for regulatory harmonisation, consumer perception studies, and sustainability assessments to accelerate market penetration while mitigating long term exposure risks. We provide a forward looking synthesis of the global food marketplace, noting that nanotechnology; biotechnological scale up will resolve stability and scalability bottlenecks currently limiting natural additives/preservatives. We foresee sustainable, consumer acceptable systems that maintain antimicrobial, antioxidant, and anti-enzymatic functions without the carcinogenic or microbiome disruption profiles sometimes linked to synthetics. Complementing these perspectives, Chen et al ³² draw attention to the substitution potential of plant-based additives through edible coatings/films and nanoencapsulation, which enhance bioavailability, mask off-flavours, and extend protective effects while aligning with green chemistry principles. Together, these sources outline a roadmap that balances industrial feasibility with public health priorities: viz, pilot scale validation of hybrid formulations, longitudinal human trials to confirm safety profiles, and policy frameworks that incentivise clean label transitions. The coming decade will likely witness regulatory approval of novel encapsulated natural additives, reduced maximum permitted levels for synthetics, and widespread adoption of hurdle technologies that deliver safer, higher quality food with measurable environmental added benefits.

Table 6.

Future Research Directions, Long Term Policy/Industry Implications, and Opportunities for Natural and Hybrid Preservation Systems, Along With Key Challenges and Strategic Recommendations for Transitioning

Focus area	Proposed innovation	Opportunity	Recommendation	Challenge	Quality assurance	Food safety	Human health	Approach	Limitations	Reference
Minimally processed foods	Subcritical water extraction	Low cost production from untapped sources	Broader source investigation	Higher commercial costs	Nutritional integrity retained	Microbial safety boost	Natural solution	Extraction method review	Few current applications	30
Spice derived antimicrobials	Encapsulation and edible films	Synergistic efficacy and reduced resistance	Sustainability assessments	Cost effective scaling	Enhanced shelf-life	Pathogen inhibition	Anti-inflammatory benefits	25 spice evaluation	Real matrix data limited	31
Clean label shift	Nanotechnology and hurdle tech	Sustainable consumer systems	Biotechnological scale up	Stability barriers	Multifunctional preservation	Spoilage control	Carcinogenic risk avoidance	Strategy analysis	Regulatory harmonisation	33
Plant based substitution	Nanoencapsulation and coatings	Improved bioavailability and taste masking	Edible film integration	Synthetic toxicity concerns	Texture and consistency	Antimicrobial protection	Healthier alternatives	Technology review	Efficiency optimisation needed	32
Natural antimicrobials	Low dose combinations	Sensory neutral application	Minimal processing focus	Solvent toxicity	Quality enhancement	Safety and shelf-life	Promising alternative	Future investigation call	Commercial viability gap	30
Synergistic blends	Antimicrobial coatings	Market penetration via perception	Interdisciplinary collaboration	Allergy evaluation	Flavour retention	Foodborne control	Long term safety	Regulatory alignment	Consumer acceptance	31
Antimicrobial peptides	Biotechnological innovations	Membrane disruption mechanisms	Hurdle adoption	Scalability issues	Consumer quality	Microbial inhibition	Safer than synthetics	Marketplace synthesis	In vitro dominance	33
Edible films	Polymer encapsulated bioactives	UV protection and extended protection	Green chemistry alignment	Stability challenges	Organoleptic maintenance	Pathogen reduction	Bioactive added benefits	Substitution potential	Dose standardisation	32
Understudied sources	Solvent-free methods	Environmental impact reduction	Minimally processed emphasis	Toxic solvent use	Quality boost	Safety enhancement	Natural promise	Future investigation call	Commercial viability gap	30
Encapsulation technologies	Cost effective scaling	Competing with synthetics	Continuous innovation	Affordability and production	Shelf-life extension	Antimicrobial efficacy	Reduced resistance	Matrix optimisation	In vitro to in vivo gap	31
Biotechnological innovations	Nanotechnology integration	Sustainable systems	Regulatory harmonisation	Carcinogenic profiles	Consumer-acceptable quality	Microbial safety	Risk mitigation	Shift analysis	Stability barriers	33
Mixed organic formulations	Bacteriocins and combinations	Unexplored clean label potential	GSFA-style expansion	One-for-one replacement	Sensory retention	Bio-preservation	Transparency	Metabolite review	Market stage limitations	30
Plant based additives	Edible coatings/films	Bioavailability enhancement	Taste masking technologies	Synthetic side effects	Texture consistency	Protective barrier	Healthier profiles	Substitution pathways	Efficiency challenges	32
Synergistic combinations	Antimicrobial coatings	Novel packaging uses	Consumer perception studies	Long term exposure	Flavour maintenance	Pathogen control	Eco-friendly benefits	Sustainability focus	Regulatory standards	31
Hurdle technology	Multifunctional peptides	Metabolic interference	Biotechnology adoption	Scalability issues	Quality standards	Spoilage prevention	Safer alternatives	Future transformative	Health concerns	33
Low cost extraction	Subcritical water	Environmental minimisation	Broader exploration	Commercial disparity	Nutritional preservation	Safety boost	Natural alternative	Extraction review	Limited applications	30
Nanoencapsulation	Polymer films	Masking and stability	Green development	Synthetic toxicity	Organoleptic properties	Antimicrobial effects	Bioactive delivery	Technology insights	Dose optimisation	32
Regulatory frameworks	Spice compounds	Global sustainability	Field collaboration	Allergy/toxicity	High-quality products	Safe food	Consumer safety	Sustainability focus	Regulatory standards	31
Sustainable systems	Nanotechnology and biotech	Consumer acceptable preservation	Longitudinal trials	Regulatory harmonisation	Multifunctional quality	Microbial inhibition	Carcinogenic avoidance	Preservation development	Scalability gaps	33
Clean label metabolites	Novel combinations	GSFA integration	Regulatory streamlining	Quality sustenance	Sensory retention	Bio-preservative control	Health conscious	Innovations summary	Trial stage focus	30
Encapsulation and synergies	Antimicrobial coatings	Market penetration	Perception and sustainability studies	Toxicity evaluation	Shelf-life and flavour	Pathogen fight	Anti-inflammatory	Future research	Real matrix data	31
Plant based technologies	Edible films and nano	Greener additives	Substitution validation	Stability issues	Texture maintenance	Protective effects	Bioactive benefits	Health effects review	Efficiency needs	32
Hurdle approaches	Antimicrobial peptides	Safe systems	Interdisciplinary collaboration	Synthetic risks	Consumer quality	Spoilage prevention	Safer alternatives	Strategy examination	In vitro emphasis	33
Understudied sources	Solvent free extraction	Minimally processed foods	Broader investigation	Cost barriers	Nutritional integrity	Safety and quality	Promising solution	Future call	Commercial use limited	30
Regulatory guidelines	Spice derived	Global alignment	Scaling and cost methods	Long term exposure	Product safety	Antimicrobial	Consumer safety	Holistic approach	Guidelines gap	31
Bioactive delivery	Nanoencapsulation	Healthier profiles	Green chemistry adoption	Synthetic concerns	Organoleptic	Antimicrobial	Bioavailability	Substitution potential	Standardisation	32
Emerging innovations	Hybrid formulations	Clean label era	Business improvements	Preservation challenge	Overall quality	Safety and security	Transparency	Strategy examination	In vitro emphasis	33

Future perceptions map concrete opportunities emerging from the synthesized literature, showing how extraction innovations and delivery technologies can deliver ^shelf-life improvements and food safety assurance comparable to synthetics while enhancing nutritional value, although this still requires pilot scale studies (see Table 6). Findings in Table 6 distils persistent challenges such as cost, stability, and regulation alongside actionable recommendations including encapsulation optimisation and cross disciplinary partnerships, highlighting that targeted investment will dictate transition speed into all the recommendations in this systematic review. Evidence supports a hybrid paradigm harnessing natural bioactive strengths alongside minimal synthetic support, provided scale up studies, harmonised standards, and transparent communication maintain public trust. Realising this vision demands sustained funding for validation trials and policy incentives that reward clean label innovation, ultimately yielding safer, higher quality food systems aligned with both sustainable ecosystem and human health.

Conclusion

This systematic review synthesized and critically appraised the evidence from primary studies published between 2020 and 2026 investigating natural and synthetic food additives and preservatives. Natural and synthetic additives each retain indispensable roles, with the weight of 2020 to 2026 primary evidence tilting toward augmented utilisation of natural/bio derived compounds. Recent findings consistently signal a decisive shift toward hybrid preservation systems that integrate natural antimicrobials with smart delivery technologies while phasing down reliance on synthetic additives. Consumer preference for clean label products, coupled with documented concerns over synthetic toxicity and microbial resistance, is driving innovation in encapsulation, nanotechnology, hurdle approaches, and low impact extraction methods. Stakeholders, e.g., industry, regulators, and consumers, stand to gain from evidence driven policies that prioritise both technological efficiency and human health. Continued rigorous primary investigation remains essential to navigate the dynamic interplay of preservation, safety, and wellbeing in an increasingly resource constrained world.