Chemical and fatty acid composition of cow and sheep milk cheeses in a lamb skin sack

•Basic chemical and fatty acid compositions of traditional cheeses were determined.•Differences between cow and sheep cheese were found in terms of fatty acid composition.•Starter cultures significantly influenced the chemical and fatty acid composition.•Commercial and previously isolated autochthonous starter cultures were used.•The 45-day ripening time significantly affected the chemical composition.

In this study, the basic chemical and fatty acid compositions of autochthonous Croatian cow and sheep cheeses in a lamb skin sack (local name: “sir iz mišine”) were determined. Also, the influences of ripening period and different starter cultures on chemical and fatty acid composition of these cheeses were investigated. Samples of cow (n = 20) and sheep (n = 20) milk cheeses were produced in three different ways: from raw milk without the addition of a starter culture, from pasteurized milk with commercial starter cultures and with previously isolated autochthonous starter cultures (Lactococcus lactis S1 or Lactobacillus plantarum B or a mixture of both). Samples were taken during a 45-day ripening period (on days 0, 15, 30 and 45). The ripening time significantly affected all basic chemical parameters, while different starter cultures significantly (p < 0.05) influenced protein, fat and ash content. Ripening time had no significant effect on the representation of the investigated fatty acid groups (p > 0.05), but a significant difference was found depending on the starter cultures used and the type of cheese analysed, in terms of statistically higher proportion (p < 0.05) of polyunsaturated fatty acids in the finished sheep's milk cheese (2.58–2.97%) in comparison to the cow's milk cheese (1.93–2.14%). Fatty acids most represented in the analysed cheeses were palmitic, oleic and stearic acid.