Relationship between Microbial Composition of Sourdough and Texture, Volatile Compounds of Chinese Steamed Bread

Abstract

The objective of this work was to explore the relationship between the microbial communities of sourdoughs collected from the Xinjiang and Gansu areas of China and the quality of steamed bread. Compared to yeast-based steamed bread, sourdough-based steamed bread is superior in terms of its hardness, adhesiveness, flexibility, and chewiness. It is rich in flavor compounds, but a significant difference in volatile flavor substances was observed between the two sourdoughs. A total of 19 strains of lactic acid bacteria (LAB) were isolated from the Gansu sourdough sample, in which Lactiplantibacillus plantarum and Pediococcus pentosaceus were the dominant species, accounting for 42.11% and 36.84%, respectively. A total of 16 strains of LAB were isolated from the Xinjiang sourdough sample, in which Lactiplantibacillus plantarum was the dominant species, accounting for 75%. High-throughput sequencing further confirmed these results. Clearly, the species diversity of Gansu sourdough was higher. The volatile profiles of the sourdoughs were similar, but differences in the individual volatile compounds were detected between the sourdoughs of the Gansu and Xinjiang regions. These results point out that the differences in the microbiota and the dominant strains lead to differences in the quality of sourdoughs from region to region. This investigation offers promising guidance on improving the quality of traditional steamed bread by adjusting the microorganisms in sourdough.

Exploration of microbial profile of traditional starters and its influence on aroma profile and quality of Chinese steamed bread

“…Traditional starters from different origins had various effects on the appearance and texture of steamed bread, and the dominant Wickerhamomyces spp. showed a significant correlation with texture data 1,6 . Metabolic changes in dough were induced by the microbial diversity of traditional starters from Gansu, Anhui, Heilongjiang and Henan provinces, while the differences in amino acids, glucose, lactic acid and acetic acid were closely related to the variation in Saccharomyces cerevisiae and Lactobacillus sanfranciscensis 3,5 .…”

“…This was consistent with their aroma sensory evaluation results as listed in Table 1 and previous results. 1,15,18,40,45 However, Pediococcus (41.70% in XT-ST) showed a negative correlation with cell density (r = − 0.61), implying its inhibitory effects on XT-CSB (Supporting Information Table S2) and Weissella from HS-ST and ZJ-ST, significantly inhibiting the formation of butanal with pungent aroma (P = 0.02; r = −0.67) and inducing relatively high sensory scores (Table 1).…”

“…Chinese steamed bread (CSB) is made from wheat flour by fermentation and steaming; it represents about 40% of the wheat consumption in China. 1 It is a popular staple food of China with traditional ethnic characteristics; the main consumption areas are the wheat-producing provinces, including Shandong, Henan, Hebei, Xinjiang and Shanxi. [2][3][4][5][6] Commercial dry yeast and traditional starters are the main starters of steamed bread; the former has good fermentation properties but with bland flavor, while the latter has good flavor and texture, but the flavor and quality remain unstable and a longer preparation time is required.…”

“…showed a significant correlation with texture data. 1,6 Metabolic changes in dough were induced by the microbial diversity of traditional starters from Gansu, Anhui, Heilongjiang and Henan provinces, while the differences in amino acids, glucose, lactic acid and acetic acid were closely related to the variation in Saccharomyces cerevisiae and Lactobacillus sanfranciscensis. 3,5 Microbial diversity of traditional starters are related to their geographical origin, but few studies have been done on the microbial profile of traditional starters for steamed bread from Hebei Province, which is one of the main consumption areas of steamed bread in China.…”

“…Chinese steamed bread (CSB) is made from wheat flour by fermentation and steaming; it represents about 40% of the wheat consumption in China 1 . It is a popular staple food of China with traditional ethnic characteristics; the main consumption areas are the wheat‐producing provinces, including Shandong, Henan, Hebei, Xinjiang and Shanxi 2‐6 .…”