Abstract:
In Henan Shangqiu (SQ), Nanyang (NY), Xinxiang (XX) three region characteristic JiaoZi and fermentation production of steamed bread as the research object, it was analysed quantitatively and qualitatively the sensory and flavor substances through the JiaoZi pH and titratable acidity, lactic acid bacteria and JiaoZi count, sensory evaluation, quality and structure analysis, image analysis and solid phase microextraction and gas chromatography mass spectrometry in the different region characteristic JiaoZi steamed bread. The results showed that the pH value of the fermentation samples ranged from 5.59 to 5.92. The range of TTA was 2.12~3.40 mL. In terms of colony count, the maximum cell density of JiaoZi in XX fermentation was 3.93 lg(cfu/g) and that of lactobacillus in SQ fermentation was 3.39 lg(cfu/g) . XX fermented steamed bread was superior to the other two kinds of steamed bread in terms of texture, compression, relaxation and adhesion. In the image analysis, the slice brightness, stomata contrast, and number of stomata of XX fermented bread were the largest, indicating that its internal texture structure was better and more popular among the public. The wall thickness, coarse pore volume, and pore diameter were the smallest. GC-MS analysis showed that 65 volatile flavor compounds were identified from XX JiaoZi steamed bread, 58 types of NY JiaoZi steamed bread, and 61 types of SQ JiaoZi steamed bread. Alkenes, alcohols and carboxylic acids in XX fermented steamed bread contributed a lot to the flavor, accounting for 89.06% of the total. Olefins, alcohols and carboxylic acids also contributed a lot to the flavor of NY JiaoZi steamed bread, accounting for 79.13% of the total. Alkenes, alcohols and ketones were the major contributors to the flavor of SQ JiaoZi steamed bread, accounting for 66.05% of the total. At the same time, these three kinds of steamed bread all had their own unique flavor substances. The results showed that there were some differences in the sensory and flavor of steamed bread made by different JiaoZi, which provided theoretical support for the commercial production of steamed bread.