Specific volume is an important parameter to analyze the quality of bread which involves loaf volume and loaf weight. Fig. 2b depicted the influence of PHGG level and water level on specific volume of bread. Effect of PHGG level on specific volume of bread was more prominent than water level. Specific volume of bread showed a decrease with increase in PHGG level whereaswater level showed a little effect on specific volume. With increase in water level, specific volume of bread first decreased slightly and then
increased slightly. The decrease in specific volume of bread may be justified by diluting effect of gluten caused by PHGG which led to lower loaf volume of bread. A decrease in loaf volume of bread fortified with barley beta-glucan was also reported (Knuckles et al.,1997). Similar results were reported for bread fortified with wheat
fiber and psyllium husk fiber which reduced the loaf volume of bread (Park et al.,1997).