ON BARLEY AMYLASE AND PROTEINASE

Abstract

In view of the significance of albumin degradation products in relation to beer foam and palate fullness, and the apparent localization of amylase in the albumin fraction of barley, it appears desirable to develop means for accurate determination of barley amylase, including both free and total amylase. A suitable method for this purpose involves extraction of barley meal with 0.1 M sodium chloride solution for free amylase determination and by sodium chloride in presence of cystein for total amylase, it having been shown that the inactive enzyme is activated by reducing substances; the effect is probably independent of any influence on proteolytic enzymes. Further, proteinase activity in barley can be determined by a modification of the Anson method, using haemoglobin as substrate, and determining proteolysis either spectrophotometrically or by applying Kjeldahl's method to the soluble products formed.