Dynamic changes in pyhsical and biochemical fruit quality attributes of Morus alba L. across multiple harvests: Insights from consecutive seasons

Abstract

Background

Thanks to its high nutritional value, rich antioxidant content, and versatility in being processed into various products, white mulberries have emerged in recent years as a functional food with increasing demand. White mulberry fruits ripen gradually and fruits present different fruit quality profiles at different harvests. The varying quality profiles of the harvests determine the best evaluation methods of the fruits from different harvests including dried mulberry or molasess production.

Objective

The aim of this study was to evaluate the changes in fruit quality attributes and the products of different white mulberry genotypes during the harvest period of different white mulberry genotypes.

Method

Fruit samples from four genotypes (seeded ‘Baldut’ and ‘Elazığ’, and seedless ‘Kaem Beyazı’ and ‘Yediveren’) were collected at 5-day intervals across two consecutive years, totaling 11 harvests per year. Fruit weight, must and drying yield, L*, a*, b* color indices, titratable acidty (TA), soluble solid content (SSC), total phenolic content (TPC), DPPH and ABTS antioxidant capacities, and HPLC fructose and glucose contents were measured in each harvest.

Results

Fruit weight ranged from 1.36 g (final harvest of ‘Kaem Beyazı’) to 3.11 g (5^th harvest of ‘Baldut’). The highest must yield was observed in first harvest of ‘Elazığ’ (78.9%). The highest drying yield was recorded in last harvest of ‘Baldut’ (33.9%). SSC, drying yield, a* color, and sugar contents increased with the advancing harvests, whereas must yield, L*, and b* color of fresh fruit decreased. Even though TPC and DPPH did not show consistent changes throughout the harvests, ABTS antioxidant capacity were found higher in latest harvests.

Conclusions

Early harvests were more suitable for molasses production, while mid-to-late harvests were better for drying. The findings offer strategic insights for targeted mulberry cultivation and optimal harvest timing.