부산대학교 도서관

Modern metagenomics techniques in combination with next generation sequencing are increasingly used for research of numerous environments inhabited by diverse microbiota. In the present study we focused on a rather unusual environment for their growth, a forgotten bottle of blended Scotch whiskey. Whiskey is a world-known popular spirit, traditionally produced in a series of steps comprising malting of barley, fermenting the malt to an alcoholic wort, distilling and at least 3-year long maturation in oak casks, followed by filtration. In the process, notably in the fermentation, microorganisms play a crucial role. However, we were primarily interested in potential microbiological and chemical changes that might have taken place over the years while the half-empty whiskey bottle was left open. We found that only a very low number of aerobic mesophilic bacteria survived in it while the ethanol content decreased from 40 % to approximately 30 %. Interestingly, the metagenomics analysis showed there was a large and diverse microbial community present in the forgotten whiskey. Among the most abundant microorganisms were members of human commensal microbiota, some potentially disease-causing and also food spoiling bacteria, in particular genus Pseudomonas. Surprisingly, we even found a non-negligible number of typically environmental bacterial species.