Improvement of nutritional value in cereals

Abstract

This investigation is principally aimed at exemplifying the developmental sources (italicized below) that are the requisites to obtain an adequate nutritional role for cereals in feeds and foods. Barley for feed purposes is given central attention and is compared with wheat, rye, ryewheat and oats. The importance of basic research in plant and animal sciences is briefly reviewed, and also complemented with experimental results. Development of reliable, rapid and inexpensive screening methods is stressed and exemplified by a feeding test with mice and a dye-binding (DBC) method for estimating lysine. Screening analyses for quality characters in cereals are used in inventories studying cereals, feed supplements, and complete commercial feeds. The information obtained is tentatively evaluated and is used for promulgating a provisional development programme for Swedish conditions. The research that has been carried out for the realization of the programme is discussed with attention focused particularly on the development of high-lysine barleys and a high-temperature drying process for cereals for livestock feeds. A high-protein, high-lysine barley line (Hiproly) was recovered from the World Barley Collection employing the DBC method. A recessive gene (lys) was found in Hiproly that increases lysine and other essential amino acids in the endosperm independently of protein content. Genetical, plant-physiological, biochemical, ultrastructural and animal nutritional aspects of high-lysine genes in barley and in maize are extensively discussed along with concomitant analyses of the lys gene. Problems involving grain deterioration and its prevention in Scandinavian cereal production are considered. In addition, the effect of heat on the availability of lysine in cereals during storage, drying and baking is experimentally studied. On the basis of the observations and results, a full-scale, rapid, high-temperature drying method has been developed that is adopted in agriculture in Sweden. The results are summarized and confronted with the operational concept of nutritional value. The needs for retrieval of information from research and from the applied sphere of cereal utilization — all for optimal exploitation by plant breeders — are discussed for conditions prevalent in Sweden, on the one hand, and in the developing countries, on the other. Research data from basic sciences as well as information from regional inventories on technological, ecological and social conditions have to be co-ordinated in a synthesis in science specific for each country. New solutions must be transferred to the individual and group level of people who can use them as selection criteria favouring survival and quality in economy and life.