Chemical Composition, Fatty Acid Profile, and Lipid Quality Indices in Commercial Ripening of Cow Cheeses from Different Seasons

The aim of the study was to compare and demonstrate whether commercial rennet ripening cheeses available on the market in summer and winter differ in their chemical composition, fatty acid profile, content of cis9trans11 C18:2 (CLA) acid and other trans isomers of C18:1 and C18:2 acid and whether they are characterized by different values of lipid quality assessment indices. The experimental material consisted of rennet ripening of cheeses produced from cow’s milk available in the Polish market. The first batch contained cheeses produced in winter and purchased from the market between May and June. The second batch contained cheeses produced in summer and purchased between November and December. Chemical composition was analyzed by FoodScan apparatus. The gas chromatography (GC) method was used to determine the content of fatty acids. Results obtained in the presented study indicate that the chemical composition, content of fatty acids trans isomers, and lipid quality indices varied between summer and winter cheeses. The summer cheeses were richer sources of MUFA and PUFA compared to winter cheeses. Summer cheeses were also characterized by lower content of SFA, higher content n − 3, lower n − 6/n − 3 ratio, and higher content of DFA. Higher contents of CLA and trans C18:1 and C18:2 were found in summer cheeses

Effects of Single Nucleotide Polymorphisms in the SLC27A3 Gene on the Nutritional Value of Sheep Milk

The current research was undertaken to use the genetic potential of animals to obtain high-quality dairy products. Single nucleotide polymorphisms (SNPs) in SLC27A3 gene were identified in Zošľachtená valaška sheep using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Correlations between genotypes and milk composition and nutritional value were analysed This study showed that milk from sheep with TT genotype in the SNP4 locus was characterised by higher (p < 0.01) fat and dry matter content and lower lactose concentration, compared to sheep with AA and TA genotypes, respectively. Moreover, it was found that animals with GG genotype in SNP1 produced milk with higher C18:1n9c, C18:1n7t, CLA, and other unsaturated fatty acids (UFAs) content than sheep with TT. Additionally, milk from animals with CC at the SNP3 locus had significantly higher (p < 0.01) levels of UFAs than milk from sheep with other genotypes in the SNP3. In summary, it may be concluded that milk from animals with TT genotype of SNP4 is characterised by higher fat and dry matter content. Whereas, milk from sheep with GG in SNP1 and with CC in SNP3 is characterised by higher content of UFAs, which increases milk value as material for functional food production