Fatty Acid Profile and Lipid Preventive Score of Fat in Milk of Tsigay and Karakachan Sheep Reared in the Rhodopes Mountain

Trakya University Agricultural Faculty, BG - 6000 Stara Zagora, Bulgaria


MIHAYLOVA, G., 2006. Fatty acid profile and lipid preventive score of fat in milk of Tsigay and Karakachan sheep reared in the Rhodopes Mountain. Bulg. J. Agric. Sci., 12: 475-481

The study was performed on individual sheep milk samples, obtained from 2 groups of sheep with 5 animals in each, reared in the Rhodopes mountain: Group I - Tsigay sheep and Group II -Karakachan sheep. The milk was analysed during the April-July period when sheep grazed on pastures. Four milk controls were performed at one month interval, according to the Instruction of milk productivity control.
The extraction of milk fat was performed by the method of Rose-Gottlieb, the solvents were evaporated on a vacuum-rotary evaporator and obtained fat was frozen at -18°C until analyzed. The methyl esters of fatty acids were analyzed on a Pay Unicam 304 gas chromatograph with flame ionization detector, capillary column EC™ WAX (30 m x 0.25 mm, I. d.; 0.25 UMn film) and hydrogen as a carrier gas. The groups of fatty acids, the fatty acid ratios and the lipid preventive score were calculated.
It was found out that the Tsigay sheep milk had a higher content of capric acid than Karakachan sheep milk (10.31% and 7.49%, respectively). The sum of caproic, caprylic and capric acids was higher in sheep milk from group I -18.01 % vs 16.73% in group II. The least variable fatty acid ratios wereC18:0/C16:0,C18:l/C16:0,C12:0/C10:0,C18:3/C18:2 and C4:0/C6+8. The polyunsatu-rated fatty acids content was similar in both groups (4.96% 5.00%). Although the difference was insignificant, the milk of Tsigay sheep had closer values between the lipid preventive score and fat content.

Key words: sheep milk, milk fat, fatty acid, lipid preventive score