Nutritional status of the protein of corn-soy based extruded products evaluated by rat bioassay.

A rat bioassay was conducted to preclinically evaluate nutritional quality of two supplementary foods (SFs) developed based on corn and soy blends for feeding preschool children. The SFs prepared by extrusion cooking and subsequently modified to taste either sweet or salty provide 395 +/- 2 kcal of energy and 20 +/- 2 g protein per 100 g of food. The proximate constituents and energy contents of SFs were within the ranges prescribed for processed weaning foods and could satisfactorily meet the requirements of preschool children. Groups of male weanling rats were fed SFs for 4 weeks to evaluate the protein quality. The body weight gain of rats fed with SFs were significantly higher than those fed with skimmed milk powder (SMP) diet as control. The protein efficiency ratio and net protein utilization results of SFs were not significantly different (p > 0.05) from values of control group. It is inferred that these SFs were nutritionally comparable to SMP.