Study on Flavor Components of Steamed Bread Fermented by Different Starters

Solid-phase micro-extraction (SPME) and gas chromatography-mass spectrometry (GC-MS) were adopted to study the flavor components of steamed bread fermented by three different starters (YFSB, steamed bread fermented by yeast, LPSB, steamed bread fermented by yeast and Lactobacillus plantarum, and JZSB, steamed bread fermented by yeast and Jiaozi). The results showed that the flavor substances of all kinds of steamed bread mainly included alcohols, esters, aldehydes, hydrocarbons, benzene rings, ketones, ethers, acids and heterocycles. The alcohol content were the highest among the flavor substances, 51.71%, 41.53%, and 54.15% for YFSB, LPSB and JZSB, respectively. Compared with the other two kinds of steamed bread, LPSB contained less alcohol, but more esters and aldehydes. The content of aldehydes was about twice of the other two kinds of steamed bread, which was 16.61%. The content of hydrocarbons and acids in JZSB was higher than the other two kinds of steamed bread, 11.47% and 5.33%, respectively, and the content of benzene ring was lower than the other two kinds of steamed bread, only 4.57%. The flavor components of the three kinds of steamed bread were different in type and relative content, indicating that the starter had a great influence on the flavor of steamed bread. Different kinds of starters could be adopted in proper ratio to achieve high quality steamed bread with rich flavour.