Effect of tristearin and other functional fats on blood lipids in hamsters

Groups of hamsters were fed diets containing tristearin (TS), a baker's shortening (BS), soybean oil (SO), a blend (BL) of TS and SO, or a hard fat (HF). Only BS contained trans fatty acids. After four weeks, serum total cholesterol (T-CH) levels were most elevated in hamsters fed HF. In comparison, hamsters fed BS, BL, or SO showed 13.3, 15.4, or 23.7% reduction in serum T-CH, respectively. Reduction in serum T-CH was even more pronounced in hamsters fed TS. However, this group also showed poor weight gains, apparently because only 16.2% of ingested TS was absorbed. Reduction in T-CH occurred due to reduction of both high-density-lipoprotein (HDL)-CH and non-HDL-CH, but the pattern of reductions still favored lower T-CH-to-HDL-CH ratios. Like T-CH, serum TG levels were also most elevated in hamsters fed HF with other groups showing significant reductions. Liver CH responses did not conform to responses observed for serum CH and TG levels. Tested in selected baked products prepared in-house, blended fat (BL) was found as functional as regular BS, and it contained no trans fatty acids.