Isolation and characteristics of high-yield bacterial strains in citrus vinegar fermentation

In order to select the special strain suitable for citrus vinegar fermentation and improve fruit vinegar quality，the most excellent acetic acid bacteria were screened and identified from the nature fermented citrus vinegar by natural fermentation，using calcium tablet，and their production performances were determined，including acetic acid production，ester production，alcohol resistance and heat resistance. The results indicated that strains of ZY.C4 and ZY.A5 produced higher acetic acid than the other 39 strains. And the results of identification experiment showed that strain ZY.C4 was Acetobacter malorum，and strain ZY.A5 was Acetobacter rancens. The properties of ZY.C4 strain were more excellent than those of ZY.A5 and control strain，and the optimum fermentation time，temperature and alcohol concentration for it were 5 days，31℃ and 7%，its performances were steady after transplanting 5 times. A. malorum ZY.C4 was suitable for citrus vinegar fermentation