Influence of heated and nonheated partially hydrogenated dietary fats on ileal chyme fat and fatty acid composition of ileal mucosa in pigs.

In this study the effects of partially hydrogenated chemically processed fats (CPF) and non-CPF on the ileal chyme fat and the fatty acid (FA) profile of the ileal mucosa and the subcutaneous tissue were analyzed. Samples were collected via an ileocutaneous fistula. For three months pigs were fed a control meal or diets containing either non-CPF high on 16:0, non-CPF high on 18:2 n6, CPF with 50% trans-18:1 or 20% trans-18:1. The latter fat was used after heat treatment. With both CPF diets, the fat content in the ileal chyme was three times higher than with non-CPF. In contrast to subcutaneous tissue reflecting dietary composition, changes in FA profile of ileal mucosa were restricted. Each non-CPF resulted in an increase of the characteristic major dietary FA. Both CPF increased the mucosal trans-FA percentage from 0 to 12% on average, although dietary composition was different. This study suggests: (1) less effects of trans-FA on the regulation of intraluminal fat load compared to saturated and cis-polyunsaturated FA, and (2) higher mucosal incorporation of trans-FA with heated CPF. This may play a role in the development of epithelial lesions in the ileum, which are known following ingestion of these fats.