Nutritional quality of rice protein compared with whole egg protein.

The nutritional quality of rice protein was compared with that of whole egg protein by slope ratio assay. Diets for each food at four levels of protein, 4, 6, 10 and 15% and a protein-free diet were given to male weanling rats of the Sprague-Dawley strain for 21 days. The slopes of the regression lines of the whole egg and rice groups calculated from the changes of body weight (Y in g/21 days) with nitrogen intake (X in g/21 days), including and (excluding) zero protein group were, respectively, Y=27.39 X-12.26 (Y=24.41 X-1.86) and Y = 13.86 X-8.06 (Y = 12.54 X +0.50). Assuming a potency of 100 for the egg protein, the relative potency of rice estimated from body weight gain with nitrogen intake was 51 (51). The values for rice calculated from body water gain and nitrogen retention with nitrogen intake were, respectively, 51 (47) and 46 (44). These values were compared with RNV of several varieties of conventional rice and high-protein rice.