Maiorchino cheese: physicochemical, hygienic and safety characteristics

This study assessed the physical, chemical, and microbiological characteristics of traditional Maiorchino cheese (Italy) made from raw ewe’s milk or from a mixture with goat’s milk. Cheese samples from the same batch were analyzed after 20 days and 6, 8, 12, 17 and 24 months of ripening. A decrease in moisture level lead to progressive total solids concentration (fat, total nitrogen, total solids and chloride) during ripening. Aw values decreased from 0.97 (day 20) to 0.85 (month 24), while pH increased from 4.99 to 5.41 (6 months) followed a by reduction until 4.85 (month 24). In samples analysed 20 days after cheesemaking, aerobic mesophilic count was 1.8•107 CFU/g, Enterobacteriaceae were 2.7•106 CFU/g, Staphylococcus spp. were 1.8•104 CFU/g, and yeasts 4.5•105 CFU/g. Sulphite reducing bacteria were not found. Lactic bacteria count at 30°C (LAB30) and 42°C (LAB42) was about 108 CFU/g (day 20); LAB30 reduced until month 8; LAB 42 reduced until month 12; both were not detectable at months 17 and 24. Cheese-making process does not consider commercial starter cultures and LAB group is heterogeneous because of its natural microflora. Yeasts were considered as typical microflora of Maiorchino. Volatile compounds were examined at 6, 12 and 24 months of ripening; 54 components were identified. Statistical analysis showed that the seasoning period of 12 months was the best for Maiorchino flavour attributes. The characterisation of Maiorchino traditional cheese may be considered as significant for this old traditional product, with the aim of obtaining the PDO certification.