Files

Abstract

Theanine (T) and polyphenols (P) enriched fractions obtained from decaffeinated black tea dust by fractionation on a XAD resin, were incorporated into wheat bread formulation. The effect on dough properties and quality characteristics of supplemented breads was investigated. The development time and mixing resistance of dough was significantly increased by P fraction addition, indicating a stronger dough structure. P inhibited the Gram-positive bacteria, while E. coli was only inhibited by T fraction. Addition of P fraction provided an extension of bread shelf life up to 4 days as compared to control bread, while T fraction increased shelf life for 1 day. P fraction hindered the retrogradation of amylopectin which had no antifirming effect in bread. During storage, starch retrogradation in P bread crumbs was significantly retarded as compared with the control. P fraction produced darker, harder and coarser crumb structure and lower loaf volume. Crumb hardness was negatively correlated with bread volume (r=−0.90, p<0.05). The electronic nose system discriminated the bread odor based on the fraction used. Bread samples of different storage times were distinguished by e-nose with discrimination index above 90.

Details

Actions

Preview