GB673063A - Metallic compounds of amino acids and preparation thereof - Google Patents

Abstract

A complex admixture of amino acid salts of iron is obtained by enzymatically digesting a proteinous material to free amino acids therefrom and reacting the resulting mixture with an iron hydroxide, hydrated oxide or carbonate. The reaction may be carried out at room temperature in the range 60-80 DEG C. If desired, the amino acid mixture may be first reacted with a soluble salt of a metal other than iron and the required iron salts obtained by double decomposition. Suitable proteinous starting materials are, for example, casein, gelatine, yeast, soya bean flour, egg albumen, vegetable or animal albumen or a mixture of two or more such proteinous substances. The digestion may be carried out under acid, neutral or alkaline conditions. With acid digestion pepsin is added to the proteins as an enzymatic agent. In neutral digestion the preferred enzymatic agent is papain and with alkaline digester pancreatic extract is preferred. The pH value of the resulting mixture is adjusted to from 3.6 to 4.6. Iron hydrate, hydroxide or carbonate is mixed with the amino acids either substantially pure or mixed with unconverted proteins, peptones and the like in proportions to give the mixture a pH value of 6.5 to 7. In the example a mixture of casein, gelatine and water are subjected to enzymatic hydrolysis by pancreatic extract; the pH value is adjusted to between 7.3 and 8.0 by the addition of sodium carbonate and when hydrolysis is 60-70 per cent complete the pH value is adjusted to 4.3 by the addition of sulphuric acid; iron hydroxide is then added and a clear solution is obtained after filtration, which may be concentrated to any degree required.