Abstract
Until this study, the species Lactobacillus trichodes had been the only identified bacterium associated with the spoilage of dessert wines in California. This organism grows and produces a flocculent precipitate of intertwined filaments in such wines. Because of the hair-like appearance of the mass of filaments, it is commonly known as the "hair bacillus", or "cottony mold" in the industry. However, in the present investigation involving the isolation and identiication of bacteria causing a similar spoilage of several dessert wines, species of Lactobacillus were not encountered. Instead, only representatives of the two genera Bacillus and Pediococcus were isolated from spoiled wines.
A total of 25 strains were isolated including 6 strains recovered from spoiled wines and 19 cultures isolated from production and storage equipment in a northern California winery.
Thermal death time studies with three species of Bacillus indicated that the spores of these organisms are capable of surviving pasteurization temperatures in the heat stabilization of fortified wines.
Organisms of the type Pediococcus cereviseae, B coagulans, B circulans, B macerans, B pumilis, B sphaericus, B pantothenticus, and B subtilis were found. From the results obtained with one isolate subjected to a Luria and Delbruck fluctuation test, it was concluded that the cells of these organisms surviving in dessert wines become resistant by some change in the cell. Resistant cells tolerate alcohol concentrations of 20 per cent (v/v). The ability of several of the isolates to attack l-malic acid and potassium bitartrate was investigated. Spoilage of a sound wine By selected isolates was reproduced in the laboratory.
- Copyright 1962 by the American Society for Enology and Viticulture
Sign in for ASEV members
ASEV Members, please sign in at ASEV to access the journal online.
Sign in for Institutional and Non-member Subscribers
Log in using your username and password
Pay Per Article - You may access this article (from the computer you are currently using) for 2 day for US$10.00
Regain Access - You can regain access to a recent Pay per Article purchase if your access period has not yet expired.