Wheat hardness and baking properties of wheat flours

Abstract

Baking tests were made by the Rapid-Mix Test on flours from two soft and three hard wheat cultivars from a single location and on 12 composites, six each, of soft and of hard wheat selections from many locations. Maltose contents, amylose values, and starch damage were substantially and consistently lower in the soft than in the hard wheat flours. The difference was accompanied by higher water absorption in the hard wheat flours. Tested by the standard Rapid-Mix Test, the soft wheat flours ranked lower in volume of baked rolls than the hard wheat flours. The soft wheat flours showed a larger volume response to increased sugar levels in the formula, to compensate for limited starch damage, than the hard wheat flours. When the sugar in the formula was optimized, the volume potential of the soft wheat flours was realized and was equal to that of hard wheat flours on a constant protein basis. The findings imply that increased starch damage in flour (from 7 to 12%) or increased added sugar in the formula (from 1 to 2·5%) can give baking performance data that provide a more meaningful comparison and better evaluation of bread making potential of soft and hard wheat flours in plant breeding programmes and in commercial testing.