Influence of lipid extraction from different protein sources on in vitro digestibility

Abstract

Proteins are the most abundant macromolecules in living cells and their primary role in the diet is to supply the body with essential amino acids in adequate quantities for the synthesis and maintenance of body tissues. The determination of protein digestibility of foods is an important factor to estimate their quality and the in vitro methodology is a fast and easy way to perform it. This study aimed to determine the influence of lipids on the in vitro digestibility of animal and vegetable proteins. The following protein sources: oat, beef, chicken, fish and pork meats, red beans, milk powder, textured soy protein (TSP), quinoa and five soybean varieties were evaluated. Animal proteins presented higher in vitro values than vegetable proteins, except for the textured soy protein, which presented higher digestibility based on the thermal treatment. In this study, there was no statistic difference between lipid content and protein digestibility. Therefore, there is no need that samples be defatted prior the analysis of the in vitro digestibility, using an enzymatic system containing the enzymes trypsin and pancreatin, which facilitates even more the use of these methods for foods with high lipid levels in food industries.