Cereal Chem 69:233-236   |  VIEW ARTICLE

Isolation of Oat Starch from Oat Flour.

W. J. Lim, Y. T. Liang, P. A. Seib, and C. S. Rao. Copyright 1992 by the American Association of Cereal Chemists, Inc. 

Oat starch was isolated from oat flour by 1) high shear in water after a presoak, 2) low shear after digestion with protease, and 3) low shear at alkaline pH. Oat flour was soaked in water (25% solids) at 20 C for 6 hr and subjected to high shear using a tissue homogenizer. After 1 min of shearing followed by centrifugation, the yield of starch (1.3% protein) was 70%, based on oat flour. Two bases were used to isolate oat starch at different concentrations and stirring times. Stirring for 60 min at pH 10.5 with 0.01 M sodium hydroxide (pH 10.5) or 0.03 M calcium hydroxide (pH 11.0) led to 71-75% isolated starch with 0.3% protein. Digestion of oat flour (25% solids) with Aspergillus oryzae protease at pH 7.5 and 37 C for 6 hr gave 78% starch with 1.1% protein. Oat starch isolated with sodium hydroxide showed a delayed pasting temperature and increased paste consistency in the amylograph compared to starch isolated by high shear or calcium hydroxide. The same phenomena was observed in wheat starch isolated with 0.01 M sodium hydroxide but not in corn or rice starch.