Мастнокиселинен състав на мляко от биволици при интензивно и пасищно отглеждане

Abstract

With the aim to assess the fatty-acid profile of buffalo milk from intensive and pasture farming system, the study included two farms. Farm 1 assigned 9 non-grazing buffaloes raised on green fodder or maize silage, and Farm 2 – 8 buffaloes on pasture until November and hay in winter. Individual samples of milk, taken in 7 monthly test days from August to February, were subjected to the Roese-Gottlieb lipid analysis. Analyses of variance were carried out per each fatty acid (FA), including the effects of farming, test day, milk yield and fat content. Farming system was established to be significant source of variation of all individual monounsaturated and polyunsaturated FAs (PUFA) and total PUFA. All PUFAs, except C20:3n3 and C20:2n6, showed better values in the milk from the buffaloes on pasture – more than 2-fold difference in total conjugated linoleic acids (0.913%) and rumenic acid (0.829%) in particular, in alpha-linolenic (0.145%) and gamma-linolenic (0.502%) acid, and in omega-3 FAs (n3), rendering n6/n3 ratio definitely lower (1.99). This applies also to greater extent to trans-C18:1 (4.027%) and vaccenic acid (2.323%) in particular, and to lesser to atherogenicity (2.44) and thrombogenicity (3.21) index. While C18:4n3 was found to increase, vaccenic and gamma-linolenic acid decline throughout grazing season, as well as conjugated linoleic acids with the exception of a peak in December. C20:5n3, C22:5n3 and C20:3n6 are characterized by such even more pronounced peak.