Journal of Cereal Science vol:39 issue:1 pages:85-90
Starch was isolated from rye flour by alkaline extraction or Pronase treatments. Both procedures led to starches of comparable purity. The present first report on the use of proteolytic enzymes in rye starch isolation showed that such treatment resulted in the highest starch yields. The rye starches had A-type granules with average particle size of 31 mum. The Pronase isolated starch had lower differential scanning calorimetry gelatinisation temperatures than the alkaline extracted starch. Defatted rye flour resulted in a Pronase isolated starch with lower peak and higher end viscosities. Wheat and rye starches isolated by the Pronase procedure were of comparable purity, but a higher yield of the former was obtained. The wheat starch had lower levels of A-type granules with an average particle size of 26 mum. When compared pairwise to the rye starches, the wheat starches had higher gelatinisation temperatures, a higher pasting temperature, a higher peak viscosity and a lower end viscosity. (C) 2003 Elsevier Ltd. All rights reserved.