title: Effects of morphological changes in beer-spoilage lactic acid bacteria on membrane filtration in breweries.
abstract: Membrane filter performance was investigated using beer-spoilage lactic acid bacteria (LAB). As a result, beer-adapted LAB strains showed considerably increased penetration rate through filters, as compared with non-adapted strains. Further statistical analyses demonstrated the significant shifts in cell size distribution towards shorter rods, when Lactobacillus brevis and L. lindneri strains were precultured in beer. These results indicate that diminished cell size is responsible for the deteriorated filter performance and, therefore, beer-adapted lactic acid bacteria are regarded as a serious threat to the production of unpasteurized beers. In addition, the selection of test strains and preculture conditions are suggested to be important for the rigorous and standardized evaluation of membrane filter performance in the brewing industry.
authors.affiliation: Analytical Technology Laboratory, Asahi Breweries, Ltd., 1-21 Midori 1-chome, Moriya-shi, Ibaraki 302-0106, Japan. shizuka.asano@asahibeer.co.jp
authors.forename: Shizuka
authors.initials: S
authors.lastname: Asano
authors.forename: Koji
authors.initials: K
authors.lastname: Suzuki
authors.forename: Kazumaru
authors.initials: K
authors.lastname: Iijima
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Motoyama
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Kuriyama
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kitagawa
mesh_terms: D001515:Beer / Q000382:microbiology*; D048429:Cell Size; D004203:Disinfection / Q000379:methods*; D005506:Food Contamination / Q000517:prevention & control*; D005516:Food Microbiology; D019344:Lactic Acid / Q000378:metabolism*; D007778:Lactobacillus / Q000166:cytology* / Q000302:isolation & purification*; D008567:Membranes, Artificial; D014462:Ultrafiltration / Q000379:methods*
chemical_list: D008567:Membranes, Artificial; D019344:Lactic Acid