Gercho GERCHEV, Gyurga MIHAYLOVA
Abstract. The study was performed on bulk milk samples obtained monthly during the milking period from the Srednostaroplaninska and Teteven sheep breeds, reared on pasture in the region of Central Balkan mountains. The technological part of yogurt production was carried out at the laboratory. Extraction of fat from the milk samples was done per the Rose-Gottlieb method. The fatty acid content was established on a gas chromatograph with a flame-ionisation detector and a capillary column. Saturated fatty acids in the milk of Srednostaroplaninska and Teteven sheep had a relatively high content during the milking period – 71.793% and 70.698%, respectively, with myristic acid content of 10.778% and 10.873%, respectively. The total amount of polyunsaturated fatty acids in the examined milk was relatively low and with similar concentrations (4.145-4.437%) during the months of the grazing period. Monounsaturated acids were mostly represented by oleic acid (С18:1), and its values in the milk of Srednostaroplaninska and Teteven sheep was, respectively, 23.545% and 25.271%. No significant change in the content of fatty acids could be observed over the course of yogurt production, in comparison with raw sheep milk.
Key words: sheep milk, yogurt, fatty acids