Variability in the lysine content of wheat, rye, and triticale proteins

Abstract

Undernutrition and malnutrition are currently widespread in many areas of the world. The most serious nutritional problem is protein-calorie malnutrition among children in the developing countries. ( 5, 24). There now exists a world shortage in production of animal proteins, which are superior in nutritional quality to plant proteins. Animal production can be expanded neither easily nor rapidly to overcome the deficit. The magnitude of the imbalance between production and need for animal protein will become worse as world population increases. It is anticipated that more and more of the world's need for protein will have to be supplied by the plant proteins, as is already the case among low income groups in many densely populated areas of the world. The total current world protein consumption is estimated to be 120 million metric tons ( 14 ). Of this total, only 30,000,000 metric tons or 25 percent is supplied from animal proteins. The remainder, 90,000,000 metric tons or 75 percent, is plant proteins. Cereals, the principal source of plant protein, represent 60 percent of the world protein supply ( 14). Unfortunately, cereal proteins are deficient in several amino acids that are required by man for proper growth. Nutritional qualities of a protein are determined by the amount and the kind of amino acids which become available to the animal organism during digestion. Cereal proteins are lower in nutritional value than animal proteins. Their lower nutritive value results from a poor balance of essential amino acids. The most limiting essential amino acid is lysine ( 2, 4, 8, 12). In recent years an ever increasing number of food supplements have been developed ( 5, 6, 24 ) , which can be used to improve the diets in many underdeveloped countries. Unfortunately, these improvements seldom reach the rural people, who generally constitute from 75 to 90 percent of the total population in such countries, and it is among this sector of the population where the worst nutritional problem exists. Doubtless, this situation could be improved markedly if cereals having improved amino acid balance could be made available.