Acetic acid bacteria in Traditional Balsamic Vinegar by PCR-DGGE analysis

Aims: The greatest limits in the study and selection of acetic acid bacteria are due to the difficultyof isolating and cultivating them. A culture-independent molecular technique, PCR-DGGE (Polymerase Chain Reaction-Denaturing Gradient Gel Electophoresis), was used in order to study the acetic acid bacteria of Traditional Balsamic Vinegar.Methods and results: Primers WBAC1 and WBAC2 were successfully used with DNA extractedfrom both acetic acid bacteria strains and vinegar’s samples and they gave PCR products that allowed differentiation by DGGE. The results obtained indicate that acetic acid bacteria species involved in spontaneous oxidation process can be represented by only one dominant species.Conclusion: A change in acetic acid bacteria species during fermentation process could be supposed: Ga. xylinus was the main representative species in cooked must while A. pasteurianusbecame more prevalent in vinegar’s samples.Significance and impact of the study: This study clearly indicated that PCR-DGGE is a suitable tool for monitoring TBV microbial population and specifically acetic acid bacteria which are difficult to isolate applying conventional microbiological techniques.