Influences of hydrothermal and pressure treatments of wheat bran on the quality and sensory attributes of whole wheat Chinese steamed bread and pancakes

Abstract

This study investigated the effects of wheat bran pre-treatments by autoclaving, roasting, jet cooking, extrusion, puffing and high-temperature-high-pressure (HTHP) cooking on the properties of whole wheat meal (WWM) and the sensory attributes of Chinese steamed bread (CSB) and pancakes prepared from blends of refined flours and brans. All the pre-treatments of bran imparted negative influences on the gluten index of WWMs compared to untreated bran. Pre-hydration of bran and its incorporation into the fully developed dough of refined flour significantly improved the specific volume, surface smoothness and crumb structure of CSB. Autoclaving, roasting, jet cooking and puffing of bran resulted in no apparent positive effects on CSB sensory attributes. HTHP cooking significantly increased CSB specific volume, but negatively affected the flavor by increasing bitterness. Extrusion of bran improved CSB crumb structure, stress relaxation score and springiness. No apparent improvement in the sensory attributes was observed in pancakes with roasted, jet-cooked, extruded and puffed brans. The autoclaved bran produced pancakes of higher crumb moistness than untreated bran. The results suggest that extrusion and autoclaving of bran prior to being blended with refined flour would be effective ways to improve the quality of whole wheat CSB and pancakes, respectively.