Cereal Chem. 70:90-95   |  VIEW ARTICLE

Relationship of Flour Aleurone Fluorescence to Flour Refinement for Some Canadian Hard Common Wheat Classes.

S. J. Symons and J. E. Dexter. Copyright 1993 by the American Association of Cereal Chemists, Inc. 

Millstreams from pilot-scale millings of commercially grown wheats from the Canadian hard common wheat classes Canada Western Red Spring, Canada Prairie Spring, Canada Western Red Winter, and Canada Western Utility were used to evaluate the potential of fluorescence imaging of aleurone tissue as a flour refinement indicator. Flour aleurone fluorescence was measured using UV excitation (excitation 365 nm, barrier greater than 420 nm). Aleurone fluorescence is acknowledged to be due to ferulic acid, which is highly concentrated in aleurone cell walls. In the current study, for every wheat class examined, aleurone fluorescence was highly correlated with ferulic acid content for every millstream with the exception of bran finisher flour. Bran finisher flour gives a moderate aleurone fluorescence despite a high level of ferulic acid. For all wheat classes, break flours gave a distinctly lower aleurone fluorescence than did reduction flours of comparable ash content and color; the former have a lower aleurone content on the basis of ferulic acid content. Aleurone fluorescence has good potential for on-line monitoring of mill performance because it is strongly related (P less than 0.01) to the ash content and brightness of reduction flours, a primary determinate of mill efficiency, for all wheat classes. The relationships of aleurone fluorescence to flour ash content and flour color were homogeneous for Canada Western Red Spring wheats from three crop years and two locations but were heterogeneous between wheat classes.