[Effect of various processes on the protein quality of food based on corn and soybeans]

The present study deals with the effect of various processing methods on the protein values of Maisoy, a blend of 30% whole soybean and 70% corn. The processes evaluated were: a) lime cooking using calcium hydroxide; b) toasting, and c) extrusion cooking, using an equipment known as the Brady Crop Cooker. The same blend of soybean/corn was processed by the same three methods. In addition, a sample of Maisoy--blend produced in Bolivia with the extrusion equipment previously indicated--was also evaluated. The evaluation of all products was carried out using the protein efficiency ratio method (PER). The capacity of two of the blends, with and without amino acid supplementation, of causing changes of deoxiribonucleic acid, ribonucleic acid, and protein in the content of muscle and liver was also measured. Lime cooking as well as extrusion cooking yielded a food with a protein efficiency ratio which varied from 2.30 to 2.60. Both processes destroyed the antiphysiological factors of soybean.