Effect of aleurone‐rich fraction on texture and nutritional properties of breads

Abstract

SummaryAleurone represents a fraction of the outer endosperm in wheat kernels composed of a single‐cell layer containing a variety of nutrients, including dietary fibre (mainly arabinoxylan, β‐glucan, and cellulose), proteins, minerals, vitamins, and antioxidants (ferulic acid). In this study, aleurone‐rich fraction (0%–100%) was added to wheat flour to examine the microstructure of the bread and the crystal structure of the starch after the addition using scanning electron microscopy and X‐ray diffraction. The maximum in vitro hydrolysis rate of bread with 10%–100% aleurone‐rich fraction addition ranged from 35.69% to 65.93%, which was significantly lower than that of white bread (68.76%). Low‐field nuclear magnetic resonance revealed an increase in the amount of bound water in bread after the addition of the aleurone‐rich fraction. Further, bread containing the aleurone‐rich fraction had a higher antioxidant capacity, as evaluated by DPPH• and •OH scavenging activity. Therefore, these results indicate that the aleurone‐rich fraction may be a beneficial ingredient for the manufacture of low‐calorie and high‐fibre foods.