Improvement of the quality of steamed bread by supplementation of wheat germ from milling process

Abstract

Wheat germ, an important by-product in the flour milling industry, is known for its nutritive value. This study investigated the effects of wheat germ supplementation on the quality of steamed bread. Raw wheat germ (RWG) or defatted wheat germ (DWG) was added to wheat flour at compositions of 1–11% (w/w). Results showed that RWG supplementation increased the wet gluten content of dough, but decreased the gluten index of steamed bread compared to the raw flour. However, opposite trends were observed by addition of DWG. Both RWG and DWG had generally similar effects on disulfide bond content. The color test showed that high levels of wheat germ were associated with a decreased L∗ value and an increased b∗ value. The a∗ values stayed close to a light red color irrespective of germ type. Sensory evaluation ratings and textural analysis indicated that steamed bread with acceptable quality attributes can be prepared from wheat flour fortified with wheat germ at less than 3%.