Cereal Chem 44:403 - 410.  |  VIEW ARTICLE
Proteolytic Activity Based on a Malt Flour Substrate Interaction.

P. R. Witt, Jr., and E. A. Tousignant. Copyright 1967 by the American Association of Cereal Chemists, Inc. 

It has been established that malt contains enzymes which exist in the "bound" state and which are believed to be active in the presence of a suitable substrate. The present data reveal that the rate of casein digestion by whole (ground) malt is equaled by a comparable equivalent of filtrate from malt extracted with 5% K2SO4 containing versenate and cysteine (adjusted to pH 5.5). Dosage-response studies showed reaction rates which are linear through 15- and 30-min. periods of digestion. Extensive investigation was carried out at a reaction temperature of 40 C. Activity was higher at 50 C. and was optimum at pH 6.0. Reaction was retarded at pH 5.0 and 6.7. The relation of enzyme to substrate at pH 6.0 reveals that optimum substrate level is between 0.5 and 1.0% casein. Proteolytic values for a series of barley malts are presented. The recorded variation in proteolytic activity reflects the processing history of the malts.