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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.

To determine the cellulase activity of barley or malt, the action on solutions of ethyl‐hydroxyethylcellulose brought about by crude extracts of barley or malt is followed by means of viscosity measurements. The observed decrease in viscosity is due to fission of the β‐glucosidic linkages of the cellulose ether. Investigations of the heat stability of the cellulase showed that extracts of green malt and cured malt lost about 40% of their activity by heating at 50° C. for 30 min.; the cellulase was almost completely inactivated by treatment at 60° C under the same conditions. Extracts of barley were less heat‐sensitive than malt extracts. Kilning of green malt to Pilsner malt (final temperature about 85° C.) caused a loss of only about 50% of the original activity. Both barley and malt cellulase had a pH optimum at approximately pH 5.

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