EFFECTS OF BROMATE AND GIBBERELLIC ACID ON MALTING BARLEY

Barley was micromalted with or without gibberellic acid and with or without additions of potassium bromate. Bromate initially depressed and subsequently enhanced levels of soluble nitrogen. This can be explained by a combination of reduced proteolysis, reduced respiratory losses, reduced rootlet growth and a decline with time in the inhibitory effects of the bromate. It was most useful when applied at steep-out. Bromate added alone at steep-out enhanced malt extract. However when added with gibberellic acid (GA₃) it did not increase the extract above that obtained with GA₃ alone. This contrasts with industrial experience, and suggests a weakness in current micromalting techniques.