[Effects of technological processing on digestive and metabolic utilization of amino acids from various protein...

The use of vegetable proteins such as legumes or oilseeds proteins is often restricted by antinutritional or toxic factors. Therefore, it is usefull, in order to extend their consumption, to isolate proteins from most of the other components of the seeds. Unfortunately, the technological processes may have some deleterious effects on the nutritive value of the proteins. Moreover, the proteins isolates and concentrates need further processing to be texturated in order to look like conventional foods for humans. We used growing rats to study the effect of some of these technological processes on the nutritive value of some field bean and sunflower protein feedstuffs. We estimated the digestive utilization of dry matter, nitrogen and amino acids, and the amino acid composition of feces was used in trying to explain some decreases in nitrogen digestibility. We also studied the ability of their amino acids to be used for growth, and tried to estimate their availability from blood and muscle free amino acids determinations. It may be inferred from the results that the technologists were successfull in improving their processes, and that textured field beans and sunflower proteins of good nutritional quality may be processed now.