Journal of Pure and Applied MicrobiologyVol. 8 No. May 2014 Special Edition

Comparison of Aroma Compounds in Traditional Fermented and Inoculated Douchies, A Chinese Traditional Fermented Soybean Food

Gang Chen1*, Xiao-Hua Lin1, Wei Su2, Ying-Long Geng1, Su-Ping Jian1 and Xiu-Fang Fan1

1State Key Laboratory of Food Science and Technology, Nanchang University, Nanchang - 330031, China. 2College of Life Science, Jiangxi Science and Technology Normal University, Nanchang - 330013, China.

Received on 12 April 2014 and accepted on 09 May 2014

 

ABSTRACT

Douchi is a Chinese traditional fermented food of soybean. In this study, the cooked soybean fermented by Multi-strains (Aspergillus oryzae and Aspergillus niger), traditional method and pure Aspergillus oryzae were analyzed and compared for volatile compound by GC-MS, using the simultaneous distillation and solvent extraction (SDE) combined technique, a total of 152 volatile compounds including 30 hydrocarbons, 21 alcohols, 8 aldehydes, 33 esters, 7 ketones, 6 phenols, 18 acids, 20 heterocyclic compounds, 3 sulfo compounds and 6 other compounds were identified. Results showed that the Multi-strains fermented samples had higher contents of volatile compounds than the pure Aspergillus oryzae inoculated samples. The predominant volatile compounds in Aspergillus oryzae and Aspergillus niger fermented soybeans included alcohols, acids, esters and pyrazines, and the major volatile compounds in the pure Aspergillus oryzae fermented soybean included hydrocarbons, aldehydes, acids and alcohols. Multi-strains fermented douchi has the most volatile compounds of the naturally fermented douchi.

Keywords : Douchi; fermentation; volatile compounds.