Cereal Chem 57:310 - 314.  |  VIEW ARTICLE
Bread Staling: X-Ray Diffraction Studies on Bread Supplemented with Alpha-Amylases from Different Sources.

R. D. Dragsdorf and E. Varriano-Marston. Copyright 1980 by the American Association of Cereal Chemists, Inc. 

The effects of barley malt, fungal alpha-amylase, and bacterial alpha-amylase on starch crystallization and organization in staling breads were studied by x-ray diffraction. Comparison of x-ray patterns of fresh and stored breads showed an order of decreasing degree of starch crystallinity as follows: bread with bacterial alpha-amylase, bread with cereal alpha-amylase, bread with fungal alpha-amylase, unsupplemented bread. Those results were in direct contradiction to bread firming data, indicating that starch crystallinity and bread firming are not synonymous. Starch crystalline organization also was affected by enzyme supplementation. Starches from breads containing bacteria enzyme supplements exhibited "Vh" and "A" structures, whereas the control had "Vh" and "B" structures. A possible role of starch crystal structure in bread firming was postulated.