Organic acid profiles of traditional sourdough microbiota dominates the fermentation effect on whole wheat bread texture

Traditional sourdough fermentation contributes to improve the palatability of whole wheat product, but the key metabolic characteristic of sourdough microbiota determining the whole wheat bread texture is yet unknown. In this study, twenty traditional sourdoughs from different regions were used for whole wheat dough fermentation and bread preparation. As a result, the organic acid composition, secondary gluten structure and soluble arabinoxylan released from bran, and exopolysaccharides production differed across all the fermented whole wheat doughs, suggesting the distinct microbiota composition of sourdough starters. While all the fermented doughs showed similar rheology, the corresponding bread quality performances were distinguished from one another, among which the samples prepared with sourdoughs from Hebi and Luoyang were noted for the promoted texture. Furthermore, the hardness and cohesiveness of bread were highly and negatively associated with fermentation quotient and lactic acid, but slightly correlated to enzymatic hydrolysis of gluten and arabinoxylan as well as exopolysaccharides generation. These findings unraveled the importance of organic acid production profile in sourdough microbiota, targeting to promote the textural attributes of whole wheat bread.