A MODELING APPROACH TO ASSESS THE LEVEL AND MOLECULAR WEIGHT OF β-GLUCAN DURING BARLEY BREAD MAKING

摘要

Incorporation of barley β-glucan as a functional ingredient has many health promoting effects for humans. Composite flour was formulated by substituting the wheat flour (WF) with barley flour (BF) and other ingredients. The high molecular weight (HMw) of β-glucan in composite flour gradually degrades to medium molecular weight (MMw) and to lower molecular weight (LMw) during the bread baking process. The model observed a 25 % and 7 % reduction in HMw and MMw, respectively and a subsequent increase in LMw by up to 30 % for baked breads. A sensitivity analysis highlighted the significant impact the addition of barley flour (BF) had on the level of β-glucan and Mw distribution within the baked bread with a positive correlation coefficient of 0.70. A negative correlation coefficient of 0.70 was observed for the effect of WF addition on β-glucan content and 0.50 for its effect on Mw. The analysis also showed the importance of mixing time (Mt), fermentation time (Ft), molecular weight of WF and baking loss on the level and Mw of β-glucan in baked breads. The model serves as a tool to facilitate both product and process development for functional foods.