Identification and Characteristics of Lactic Acid Srains for Back Sybean Yghurt Frmentation

Two lactic acid strains FJAT-7926 and FJAT-7928,which had been screened as promising fermentation agents for bean yoghurt beverage,were identified and characterized in the present work.Observation under scanning and transmission electron microscope showed that both strains were rod-shaped,gram-negative and catalase-negative without spores.According to their physiological and bio-chemical properties,FJAT-7926 and FJAT-7928 were similar to Lactobacillus plantarum and Lactobacillus casei,respectively.The similarities were also indicated with phylogenetic tree of FJAT-7926 and FJAT-7928 based on their 16S rDNA sequences.In the soybean yoghurt prepared by co-fermentation of the two lactic acid strains on bean mild,the viable cell number of the bacteria strains were 4.95108cfuL-1.The pH value,acidity,content of protein of the soybean yoghurt were 4.28,71.3 and 1.62 gg-1,respectively.