Abstract:

Objective: To screen an acetic acid-producing strain for the fermentation of Changshanhuyu Tangelo vinegar. Methods: Acetic acid-producing strains were screened from spontaneously fermented Changshanhuyou Tangelo vinegar ans tested for alcohol tolerance, acetic acid-producing rate and alcohol-consuming rate. Meanwhile, the sensory evaluation of vinegar fermented by these strains was carried out and the optimal strain screened was identified using VITEK-32 automatic microorganism analysis system. Results: Three strains were screened and named HY05, HY19 and HY36, respectively. Among these strains, HY05 exhibited the best properties and could resist 14% alcohol. Alcohol was consumed quickly at 10% initial concentration of alcohol and the fastest rate of acetic acid production was also observed. Changshanhuyou Tangelo vinegar fermented by HY05 exhibited a high quality with yellow color, fragrant odor and transparent texture. Through colonial characteristic analysis and cell morphology observation, HY05 was identified to be Acetobacter pasteurianus, designated as A. pasteurianus HY05. Conclusion: A. pasteurianus HY05 was suitable for the production of Changshanhuyu Tangelo vinegar.

Key words: Changshanhuyou Tangelo, fruit vinegar, Acetobacter spp., isolation, identification