Microscopic crystalline inclusions in Mahón cheese / Inclusiones cristalinas microscópicas en el queso Mahón

Abstract

The incidence, structure and composition of microscopic crystalline inclusions have been studied in 32 samples of Mahón cheese (non-cooked pressed cheese manufactured from cow's milk) at different ripening times. Samples were observed by light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Circular, oval or kidney-shaped struc tures approximately 20 μm in diameter (range 4-65 μm), were observed in all Mahón cheese samples. The quantity of crystalline inclusions per unit surface observed in Mahón cheese was heteroge neous, with an average of 30 crystals/m². It was possible to differentiate two different structures in the crystals: the nucleus with disorganized morphology and the cortex with radial laminar morphology. The ratio between nucleus and inclusion diameters was 0.2-0.5. Crystalline inclu sions observed in Mahón cheese were studied by X-ray microanalysis in SEM and TEM. Calcium and phosphorous were found to be the most common elements present in these inclusions.

Keywords

cheese crystaline inclusions electron microscopy

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