title: Rheological and functional properties of composite sweet potato - wheat dough as affected by transglutaminase and ascorbic acid.
abstract: Effect of transglutaminase (TGM) and ascorbic acid (AA) on composite sweet potato - wheat dough functional and rheological properties was studied. Partial substitution of wheat flour with sweet potato flour at the level of 20 % significantly (P ≤ 0.05) reduced glutenin, gliadin, dough stability, protein weakening, storage modulus (G') and viscous modulus (G″). Mixolab revealed that both TGM and AA treated dough had stability and protein weakening closed to wheat dough (control), with TGM treated dough having the highest values. TGM Introduced new cross-link bonds as shown by the change of amino acid concentration, leading to an increase in storage modulus (G') and viscous modulus (G″), with G' being higher at all levels of TGM concentration. The opposite was observed for composite dough treated with AA as measured by controlled - stress rheometer. TGM treatment increased glutenin and gliadin content. Compared with the control, dough treated with AA exhibited high molecular weight of polymers than TGM treated dough. The results indicate that the TGM and AA modification of the mixolab and dynamic rheological characteristics (G' and G″) dependent on the changes of GMP, glutenin, gliadin and protein weakening in the composite dough. TGM and AA treatment could improve functional and rheological properties of sweet potato - wheat dough to levels that might be achieved with normal wheat bread. However, it's extremely important to optimize the concentrations of both additives to obtain the optimum response.
authors.affiliation: School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China.
authors.forename: Jean Bernard
authors.initials: JB
authors.lastname: Ndayishimiye
authors.affiliation: School of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China ; The State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China.
authors.forename: Wei-Ning
authors.initials: WN
authors.lastname: Huang
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China.
authors.forename: Feng
authors.initials: F
authors.lastname: Wang
authors.affiliation: Sinmag Machinery (Wuxi) Co., Ltd., Wuxi, Jiangsu 214191 China.
authors.forename: Yong-Zheng
authors.initials: YZ
authors.lastname: Chen
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China.
authors.forename: Rebaone
authors.initials: R
authors.lastname: Letsididi
authors.affiliation: Robert M. Kerr Food and Agricultural Products, Oklahoma State University Stillwater, Oklahoma City, OK 74078-6055 USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Rayas-Duarte
authors.affiliation: College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, P.o. Box 210 Musanze / P.o. Box 3971, Kigali, Rwanda.
authors.forename: Jean Baptiste
authors.initials: JB
authors.lastname: Ndahetuye
authors.affiliation: The State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122 China.
authors.forename: Xiao-Juan
authors.initials: XJ
authors.lastname: Tang
keywords: Ascorbic acid; Composite dough; Sweet potato flour; Transglutaminase; Wheat flour