Cereal Chem 69:542-546 | VIEW
Influence of Added Enzymes on the Rheological Properties of a Wheat Flour Dough.
L. Lindahl and A.-C. Eliasson. Copyright 1992 by the American Association of Cereal Chemists, Inc.
The changes in rheological properties of a wheat flour dough due to the addition of enzymes were measured. The dough, made of flour of standard baking quality, was characterized by oscillatory measurements at room temperature and after storage at 40 C. Different commercially available alpha- amylases and mixtures of alpha-amylases and proteases were added. The elastic modulus, G', increased slowly with time at room temperature, whereas during the same time (2 hr) at 40 C, a maximum value followed by a continuous decrease in G' was observed. The phase angle, delta, increased slightly with time at 40 C. The rheological properties of the wheat flour dough were clearly influenced both by the type of alpha-amylase and by mixing protease with the alpha-amylase. The presence of alpha-amylases caused a decrease in G' after a shorter period of time, and lower G' values were obtained. A time and temperature dependency of G' was evident. The change in G' related to the amount of damaged starch was also studied, and it was found that G' increased as the level of starch damage increased. This increase in G' could be compensated for by addition of more water.