Effects of green tea extract on the quality of bread made from unfrozen and frozen dough processes

Abstract

Two different green tea extracts (GTE-A and -B) as a rich source of tea catechins were incorporated into a no-time bread-making process, where bread made from the unfrozen and frozen dough processes was compared by specific volume and texture profile. GTE-A and -B both exhibited significant effects on bread volume and firmness, but to a different extent. GTE-A with higher content of tea catechins (73%) at a level of 1.5 g kg-1 flour was found to lead to a significant reduction in bread volume in unfrozen dough process and an increment in firmness during storage for 4 days at ambient temperature (22°C). GTE-B, with a lower content of catechins (60%), had relatively mild effects on the bread quality. Significantly negative effects were evident starting at a higher level of 5.0 g kg-1 flour in unfrozen dough process. Frozen storage showed more predominant deteriorating effects than the GTEs over a period of 9 weeks frozen storage at -20°C. © 2006 Society of Chemical Industry.