Fortification of fluid skim milk with conjugated linoleic acid ( CLA

Nutraceutical products make up the fastest growing segment of the U.S. food industry. Conjugated linoleic acid (CLA) occurs naturally in milk at low levels and is an anticarcinogen. Research indicates that concentrations of 1 to 3 g CLA/day would provide protective anticarcinogenic benefits. Increased levels of CLA in fluid milk would produce a nutraceutical dairy beverage. The objectives of this study were to develop a CLA fortified milk with improved nutritional properties. CLA (1 g, 2g, or 3 g /240g) and derivatized whey protein concentrate (DWPC) (0%, 0.25%, 0.5%) were added to raw skim milk prior to homogenization, HTST pasteurization and aseptic packaging. Headspace volatiles were evaluated by purge and trap gas chromatography. Viscosity was determined using a controlled stress rheometer and visual properties (L*, a*, b*) were evaluated with a colorimeter. CLA fortified skim milk had minimal levels of hexanal and sensory data did not indicate substantial flavor deterioration as compared to control. The addition of CLA increased the whiteness of the milk, but did not significantly affect viscosity. Addition of DWPC at .25% in skim milk mimicked the viscosity of reduced fat milk, however, visual properties were not affected. These results indicate that skim milk may provide a vehicle for CLA consumption and that DWPC enhances the viscosity of skim milk such that it is more similar to reduced fat milk.