Rheological, antioxidative and sensory properties of dough and Mantou (steamed bread) enriched with lemon fiber

Consumption of natural bioactive compounds such as polyphenols and dietary fiber offers health benefits. Lemon pomace, a by-product during processing of lemon juice, is discarded which contributes to environmental pollution. In the present study, lemon fiber (LF) was extracted from lemon pomace and incorporated into dough and Mantou. Results showed that the substitution of wheat flour by LF resulted in stiffer and less extensible dough with or without fermentation. Both Peleg-Normand and Wiechert models fitted well to the stress relaxation data of Mantou (R-2 > 0.99). The parameters of two models were significantly affected by the amount of LF. The hardness of Mantou increased with the increasing of the LF substitution (0-9 g/100 g flour), but the cohesiveness, specific volume and elasticity decreased with the fiber substitution. Steaming led to significant decrease in free phenolics and increase in bound form of proofed dough. These results suggest that the substitution of 3 or 6 g LF per 100 g flour can produce healthy and acceptable Mantou with higher free total phenolic content and antioxidant capacity. (C) 2014 Elsevier Ltd. All rights reserved.