Whey proteins as functional food ingredients?

Putative anti-cancer activity of whey proteins has been investigated in an animal model to evaluate their potential role in disease prevention, and to contribute to a basis for their inclusion as ingredients in functional foods. Animal feeding trials have compared the efficacy of dietary whey proteins in retarding chemically induced colon cancer in a rat model of the disease. Dairy proteins, in particular whey protein, were found to be efficacious in retardation of colon cancer in young rats compared with other dietary proteins (meat, soy). The influence of dietary whey protein on development of colon cancer in mature rats has also been examined. Results similar to those with younger animals have been demonstrated, a finding that suggests age does not significantly alter the outcome. Efficacy of whey protein fractions has also been assessed. Preliminary results suggest that diets supplemented with lactoferrin or with beta-lactoglobulin enhance protection against the development of putative tumor precursors (aberrant crypts) in the hind gut wall. The mechanism behind the apparent anti-cancer activity of dietary whey proteins in these studies may be related to their sulfur amino acid content, for which there is a high requirement in the rat, and hypothesised role in protecting DNA in methylated form. In a parallel study, a number of potential functional foods containing whey protein (flavored milk, pasta, ice cream, dessert pudding, muesli, and savory dip) have been developed in preparation for human clinical trials. The foods containing whey protein were generally highly acceptable in taste trials. These products are expected to be suitable as delivery vehicles for dietary whey protein in studies aimed at substantiating the human health benefits of this protein source. (C) 1998 Elsevier Science Ltd. All rights reserved.