INVESTIGATION OF THE FORMATION OF PHYTATE-METAL COMPLEXES

The complex formation of phytic acid with calcium-, magnesium-, zinc-and copper ions were studied in model solutions using potentiometric titration. A constant ionic back concentration (2M/dm³) was assured by NaCIO₄. The phytic acid-metallic ion ratio was 1:1. The pH-ranges investigated were the following ones Ca: 4,0-8,0; Mg: 2,0-7,5; Cu: 3,0-5,5; Zn: 3,0-5,0. Stability constants of the phytic-acid-metal complexes were calculated from the experimental data

PREDICTION OF WHEAT QUALITY - SUCCESS AND DOUBTS

Since the discovery of gluten by Beccari in 18-th century, the wheat producers, millers and bakers tried to find relatively simple methods of prediction of wheat quality particularly during breeding process. Taking in mind that endosperm proteins play the governing role in determination of wheat quality the prediction is generally based on these proteins. Early researches concentrated on relations of macrofractions, e.g. gliadin:glutenin ratio, ratio of acetic acid soluble proteins, etc. Later the gliadin polypeptides, the genes coding for these polypeptides and the variety identification came into focus of studies. More recent predictions are based on high-molecular-weight glutenin subunits. Although the latter prediction is successfully applied in many countries in wheat breeding, the low correlation between predicted and practical quality observed in many cases suggests that further studies are needed to improve the reliability of prediction. Consideration of role of other proteins and non-protein constituents of wheat may be mentioned among potential ways of further research. From the methodological point of view the use of non-destructive methods is promising

THERMODYNAMIC AND STRUCTURAL INCOMPATIBILITY IN GLUTEN CONTAINING PROTEIN SYSTEM

Model experiments were made with the ternary systems gluten (glutenin, gliadin)-casein- water and gluten (gliadin, glutenin)-sodium alginate-water. It was found that at low concentrations (1-2%) of gluten proteins the casein-gluten solutions are homogeneous. At higher concentrations, as a result of thermodynamic incompatibility, the solution separates into two phases. The same results were obtained with gluten-alginate-water systems. The solubility of gluten proteins may be extended using ionic polysaccharides. Myosin-gluten gel systems had lower strength than pure myosin gels due to struc- tural incompatibility of the system

EFFECT OF FERTILIZERS ON THE YIELD, PROTEIN CONTENT AND AMINO ACID COMPOSITION OF WINTER CEREALS

The effect of different fertilizers (nitrogen, phosphorus, potassium) and their combinations on the yield, raw protein content and amino acid composition were studied in field experiments. The levels of treatment were 200 kg/ha for nitrogen, 500-1000 kg/ha for phosphorus and potassium. Winter rye, triticale and wheat cultivar were grown in two subsequent years. Nitrogen fertilization in all cases increased the yield of grains and the raw protein content. The increase reached about 50% in average comparing with control samples grown without adding nitrogen fertilizers. Although there are significant differences between the different cereals studied, it can be generally stated that the increase in protein content is connected with a decrease in the essential to non-essential amino acid ratio. The decrease is higher if only nitrogen fertilizer is used and moderate if a combined treatment with nitrogen, phosphorus and potassium fertilizer is applied