Cereal Chem 39:81 - 93.  |  VIEW ARTICLE

Extractable Protein and Hydration Characteristics of Flours and Doughs in Dilute Acid.

D. K. Mecham, H. A. Sokol, and J. W. Pence. Copyright 1962 by the American Association of Cereal Chemists, Inc. 

When extracted repeatedly with 0.01N acetic acid, freeze-dried flour-water doughs yielded more protein than the flour from which they were prepared. The additional extractable protein appeared to be derived largely from material which, in suspensions of the flour, settled rapidly and was highly hydrated. The rate and extent of conversion to extractable protein in doughs mixed in a farinograph differed markedly among four flours. A mixograph converted more protein to an extractable form more rapidly than the farinograph. When sodium chloride (2%, flour basis) was added, both rate and extent of the changes were decreased. In doughs mixed in a nitrogen atmosphere, extractable protein initially increased more rapidly than in air, but in 20 minutes (farinograph) the increases in air were larger. In each case, the nature of the changes suggests that the conversion of protein to an extractable form is related to the characteristics of recording dough mixer curves. Both 0.1N acetic acid and pH 3.1 aluminum lactate buffer (0.017M in aluminum) gave results similar to those with 0.1N acetic acid (one flour only).