Effect of fermentation time and addition amount of rice sourdoughs with different microbial compositions on the physicochemical properties of three gluten-free rice breads

This study aimed to better understand the impact of microbial growth and metabolism on rice sourdough and their relationship with quality characteristics of rice breads. Therefore, this research determined the microbial compositions and biochemical characteristics of indica rice (IR), japonica rice (JR) and waxy rice (WR) sourdough within 72 h fermentation. And the effects of different fermentation time and dosage of rice sourdough on rheology of rice doughs, quality characteristics of rice breads were studied. The results showed that the dominant bacteria Leuconostoc changed the processing properties of rice doughs through producing organic acids and reducing sugars. Adding 30 % rice sourdough had the best effect on improving specific volume of rice breads. And IR and JR breads with sourdough fermented 48 h had the highest chewiness, cohesiveness, resilience and the lowest hardness, while WR breads had high viscosity and poor overall structure, which was not suitable for making gluten-free bread.