Cereal Chem 38:479 - 486.  |  VIEW ARTICLE

A Method for the Determination of Relative Amounts of Malted-Wheat, Fungal (Aspergillus oryzae), and Bacterial (Bacillus subtilis) Alpha-Amylase in Mixtures, and Its Application to Malted Wheat.

J. R. Fleming, B. S. Miller, and J. A. Johnson. Copyright 1961 by the American Association of Cereal Chemists, Inc. 

A method to determine relative amounts of malted-wheat, fungal (Aspergillus oryzae), and bacterial (Bacillus subtilis) alpha-amylase activities in mixtures is presented. The method depends on differences in the thermostability of the three types of amylases and the use of simultaneous algebraic equations to calculate the percentages. Results of analyses of known mixtures of the three sources agree well with known composition. The presence of fungal alpha-amylase in malted wheat was closely related to the observed development of molds. There was little bacterial alpha-amylase in any of the malted wheats. The evidence suggests that contribution of the fungus to the total alpha-amylase activity of malted wheat is due to the production of fungal alpha-amylase, and not to gibberellic acid which could stimulate the production of cereal alpha-amylase. Up to 15% of the amylolytic activity of moldy malted wheat was due to fungal alpha- amylase.