通过分离纯化，结合16S rDNA克隆文库与扩增性rDNA限制酶切分析及Biolog碳源利用特性鉴定，得出一种传统发酵酵子中主要细菌群落及其构成比例依次为魏斯氏菌属（84.62%）、乳酸乳杆菌属（8.79%）、芽孢杆菌属（3.30%）、醋酸杆菌属（2.20%）和明串珠菌属（1.10%）。同时采用固相微萃取-气质联用法分析传统酵子制作馒头中的挥发性成分，共检测出59种挥发性风味物质，其中包括17种醇类物质、8种烃类物质、15种脂类物质、9种醛类物质、4种酮类物质、5种芳香类物质和1种其他类物质，较单纯酵母菌发酵的馒头风味物质种类丰富。结合定量和定性分析得出，醇类的含量和种类是区分两种馒头的主要标志物。本研究揭示了一种传统发酵酵子中丰富的细菌菌群构成及其在发酵过程中产生的丰富风味物质，可为传统主食的工业化改进提供基础数据，同时为进一步挖掘更优质的菌种资源，研究其生物学功能，提升传统主食营养价值提供了新思路。

Microbial diversity of a traditional Jiaozi was studied by isolation and purification and 16S rDNA Clone Library technique and Amplified rDNA Restriction Analysis (ARDRA) and Biolog carbon utilization analysis. The dominant bacterium wereWeissella(84.62 %),Lactobacillus(8.79 %),Bacillus(3.30 %),Acetobacter(2.20 %) andLeuconostoc(1.10 %). The compositions of volatile components in Chinese steamed bread (CSB) fermented with the traditional Jiaozi were determined by solid phase microextraction (SPME) coupled with gas chromatography -mass spectrometry (GC-MS). 59 volatile compounds were detected in CBSs by Jiaozi including 17 kind of alcohols, 8 kind of hydrocarbons, 15 kind of esters, 9 kind of aldehydes, 4 kind of ketones, 5 kind of aromatics and 1 kind of other compounds, which was more than in dry yeast starters. Combining quantitative and qualitative analysis, the content and variety of alcohols is the main marker to distinguish the two CSBs. This study revealed that the traditional Jiaozi had a complex composition of bacteria, and produced rich flavor compounds in CBS fermentation. This study supplied the basic data for industrialization of traditional staple food and supplied strain source for the further study of biological function research and supplied a new idea of the development of nutrition of traditional staple food.