The trans fatty acid and conjugated linoleic acid content of Fulani butter oil in Nigeria

From the milk of their cows, the Fulani pastoralists who inhabit northern Nigeria and other regions of the western Sahel produce a high-fat product called man shannu or butter oil. Since cow milk and dairy products contain a variety of trans fatty acids (TFAs) and conjugated linoleic acids (CLAs) which, depending on the particular TFA or CLA, can affect human health either adversely or positively, we were interested in determining the fatty acid composition of the milk fat of Fulani cattle and the butter oil manufactured therefrom. Milk from 12 Fulani cows and three different preparations of man shannu were analyzed for their content of TFAs and CLAs. The average fat content of the Fulani cow milk and man shannu was 3.84% and 62.5%, respectively. The milk fat contained relatively large proportions of trans vaccenic acid (mean, 3.82%) and the CLA, rumenic acid (mean, 1.35%). The percentage of the 4 major trans 18:1 isomers in man shannu was 2.23-fold higher than it was in the milk fat (10.4% versus 4.61%, respectively); in contrast, the c9,t11-18:2 percentage of man shannu was 80% lower than it was in the milk fat of the Fulani cows (0.23% versus 1.35%, respectively). Eighty percent or higher reductions were observed in the proportions of a-linolenic acid, arachidonic acid, eicosapentaenoic acid, and docosahexaenoic acid in the man shannu relative to the milk fat. These data show that: (1) the fat of Fulani cow milk and man shannu both contain large amounts of TFAs; and (2) substantial quantities of the healthful CLAs and polyunsaturated fatty acids (PUFAs) are lost during the preparation of man shannu. (c) 2005 Elsevier Inc. All rights reserved.