Physico-chemical, microbiological, textural and sensory evaluation of Edirne white cheese produced from sheep, cow and goat milk during storing

In this study, it was aimed to determine some properties of Edirne white cheese during storage produced from cow, sheep and goat milk. For this purpose, physicochemical and microbial properties of cheese samples on 0th, 30th, 90th, 150th and 180th days of storage, and textural and sensory properties on 90th, 150th and 180th days of storage were investigated. The dominant microflora in cheese samples was identified by MALDI-TOF MS. The differences between the chemical parameters of the cheese samples during storage were significant (p<0.05). It was determined that the titration acidity, maturation index, ash, salt, salt in dry matter and water-soluble nitrogen contents of the cheeses increased, but the pH values and protein contents, decreased during storage. While a decreasing was observed in the enterococci counts of cheese produced from cow and goat milk during storage (p<0.05), no significant change was detected in cheese produced from sheep milk after the 30th day of storage (p>0.05). Enterococcus faecium is determined at during storage in cheese produced from sheep milk, but at the beginning of storage in cheese produced from cow and goat milk. Water-soluble extracts were obtained from the cheese samples on the 0th, 30th, 90th, 150th and 180th days of storage. Peptide profiles in the extracts were analyzed by RP-HPLC. In all three cheese samples, the peak diversity increased due to proteolysis during storage and the peaks concentrated between the 20th and 50th minutes of the chromatogram. The extracts were also evaluated for their proteolytic, antioxidant, iron chelate, ACE inhibition and antimicrobial properties. The difference between the proteolytic activities of cheese extracts is significant and the highest value was determined at the end of storage in cheese produced from cow's milk (p<0.05). Antioxidant activity was determined by ABTS•+ and DPPH methods. With the ABTS•+ method, the highest TEAC (mM Trolox/g) value was determined in the cheese produced from goat's milk on the 30th day of storage, and the highest DPPH value (68.84%) in the cheese produced from cow's milk on the 90th storage day (p<0.05). The highest iron chelate activity was determined in cheese produced from cow's milk on the 90th day (37.63%) of storage. The highest ACE inhibition activity was determined in cheese produced from goat's milk on the 90th and 150th days of storage. Hardness, gumminess and adhesiveness values in cheese samples increased during storage and the highest average values of these parameters were determined in cheese produced from goat milk. According to the results of sensory analysis, it was determined that fermented, salty, bitter, rancid (Free fatty acids), sour and bite taste values increased, while whey and creamy taste values decreased during storage in all three cheese samples. Key words: White cheese, peptide, proteolysis, water soluable extract, MALDI-TOF MS