Abstract
Graded flour was prepared from the hard-type wheat grain 1 CW by the polished-grading method and the effect of the flour quality on the dough and baking properties was studied. Thegraded flours contained large amounts of ash or dietary fiber as compared with a conventionally milled hard-type 1 CW flour (CW). These graded flours also had larger amounts of K, Ca and Fe than CW. All the graded flours, except for the outermost layer, distinctly increased in water-soluble pentosan as compared with CW. Moreover, they contained higher β-amylase or diastatic activities and also higher amounts of damaged starch than CW. The specific volumes of the bread made from the graded flours were distinctly smaller than that of CW . None of the graded flours alone had a favorable effect on the bread firmness. For the viscoelastic properties, all parameters of the graded flours tested distinctly higher than those of CW. Microscopic observations of the graded flour dough alone indicated that the co-existence of bran could not produce a favorable gluten ma trix to result in bread of a good quality. These results suggested that graded flour alone could not make dough with the desired baking properties, because of the high amounts of diastatic activity, damaged starch, dietary fiber or wheat bran.
