Evaluation of Linear Programming Techniques in Formulating Human Diets with Rat-feeding Tests

Abstract

Diets in which the chief source of calories was either rice or wheat were formulated by linear programming to meet the requirements of the preschool child for energy, protein and amino acids. Chicken, fish, beef, eggs, whole milk, soy flour and amino acids were used to supplement the cereals to provide the necessary levels of protein and amino acids. Control diets based on egg protein and glucose were formulated to either satisfy or provide an excess above these requirements. The diets were compared in rat feeding tests. Rats fed diets based on wheat supplemented with intact protein or the amino acids lysine and methionine grew at a rate similar to those fed the control diets formulated to just meet the requirements. Rats fed diets based on rice supplemented with intact protein grew at a rate considerably faster than the control diet and also made comparatively faster growth than those fed the wheat diets. The studies indicate that linear programming can be used successfully to formulate human diets based on wheat. However, due to insufficient information on the nutritive value of rice and on the correlation between analytical and nutritive value of rice for humans, linear programming of diets based on rice was not completely successful as measured by uniformity of results. Requirements can be met by fortification of wheat with lysine and possibly methionine with no additional intact protein whereas fortification of rice with lysine alone is not satisfactory. J. Nutr. 103: 179-188, 1973.