Effect of heat processing on the profiles of trans fatty acids and conjugated linoleic acid in butter oil

Sman or traditional butter oil (TBO) is known to be rich in saturated fatty acids (SFA). Meanwhile, published information about trans fatty acids (TFAs) content in TBO remains unexplored. Therefore, a comparison of the fatty acid (FA) composition of traditional butter (TB) and (TBO) with emphasis on geometric and conjugated linoleic acid (CLA) isomers was undertaken. Both TB and TBO accounted for a high level of SFA with significant high content in TBO (p < 0.05). Total TFAs in TBO were more than twice the content in TB (8.23% vs. 3.85%, respectively, p < 0.01). An increase by 1.81 and 2.9 times was observed for trans monounsaturated FAs and trans polyunsaturated FAs in TBO compared to TB, respectively. Vaccenic acid (VA), the predominant TFA in both TB and TBO, was increased by 100% in TBO (p < 0.001). Trans-linoleic acid isomers were 1.84-fold higher in TBO than in TB. The contribution that CLA made to the total FA was increased by 1.48-fold for TBO. In general, it was found that TBO contains high levels of TFAs and CLA. Thus, TBO represents a mixture of FAs with different configurations from natural and technological origins, having potential conflicting effects on human health.