Evaluation of injury to Saccharomyces rouxii YSa40 cells in low water activity/pH glycerol/CPB stress system

• Main Authors: Yeoh, T. K., Cheah, Yoke Kqueen, Davies, Roland
• Format: Article
• Language: English
• Published: Faculty of Food Science and Technology, Universiti Putra Malaysia 2012
• Online Access: http://psasir.upm.edu.my/id/eprint/41051/1/Evaluation%20of%20injury%20to%20Saccharomyces%20rouxii%20YSa40%20cells%20in%20low%20water%20activitypH%20glycerolCPB%20stress%20system.pdf; http://psasir.upm.edu.my/id/eprint/41051/; http://www.ifrj.upm.edu.my/19%20%2801%29%202011/%2813%29IFRJ-2011-056%20Cheah.pdf

Mid-exponential phase Saccharomyces rouxii YSa40 cells subsequently stressed at low a w/pH in the 0.64 a w/pH 3.5 glycerol/CPB system became injured. Such injury was detected by the loss of ability of the stressed population to form colonies on secondary-stress plating medium (glycerol/BM agar at 0.94 a w/pH 3.5 (lactic acid)) while colony forming ability on secondary non-stress plating medium (sugars/BM agar at 0.94 a w/pH 3.5 (lactic) was unaffected. The injury was shown to be due to sensitivity to glycerol/lactic acid. Results of the present study will be useful for achieving complete decontamination of 'Intermediate Moisture Foods' against xerotolerant molds and yeast.