Digestion of vegetable protein in monogastrics. Pea proteins as an example.

摘要

Protein digestion in monogastrics, mainly pigs and poultry, is reviewed. Peas, an important protein-rich European crop, is chosen as an example because of the high variability of digestibility of the proteins of this feedstuff. After considering peaprotein composition and digestibility in monogastrics, various compounds potentially implied in explaining the observed results, are presented. The antinutritional factors of this legume can have a negative effect. Other pea or dietary compounds such assaccharides or lipids may be implied. Moreover, protein structure leads to varying susceptibility to hydrolysis. Thus some characteristics, such as significant hydrophobicity, high glycosylation level, secondary structure rich in beta-sheets, compact tertiary structure and disulphide bonds seem to have a negative impact on protein hydrolysis. Technological processing of the diet may affect protein digestion. Thus, grinding can increase digestibility. Likewise heat processing such as pelleting or extrusion, as long as the conditions are not extreme, can improve protein digestion. Thus excreted nitrogen depends on several factors. This nitrogen loss is composed of proteins and peptides, whose origin must be determined (diet or endogenous) in order to suggest solutions to reduce it.