HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Wang, M. Y. Articles by Lobben, J. C. Search for Related Content PubMed PubMed Citation Articles by Wang, M. Y. Articles by Lobben, J. C.

Destruction of Psychrophilic Strains of Bacillus by Chlorine

Department of Food Science and Technology, University of California, Davis 95616

ABSTRACT

Resistance of spores to chlorine was studied with four strains of Bacillus that grew at low temperatures, and the resistance of vegetative cells was determined for one strain, Bacillus cereus. D Values determined from the straight portions of survival curves for spores of Bacillus pumilus, Bacillus laterosporus, and culture DPL treated with 150 ppm chlorine at 25 C and pH 7.0 were .45, .75, and .85 min, respectively. At lower pH or higher temperatures the sporicidal action of chlorine was greater. D Values for B. cereus treated with 150 ppm chlorine at pH 5.2, 7.0, and 8.0 were .lo, .25, and 1.10 min, respectively, in tests run at 25 C, and .10 and .15 min in tests run at 75 and 50 C (pH 7.0). The influences of increased temperature and lowered pH were additive. At pH 5.2 and 75 C, 25 ppm chlorine reduced the viable count of spores four decimal reductions in 1 min. and hipher concentrations of 0 chlorine were even more germicidal. Vegetative cells adjusted to pH 7.0 and treated at 25 C were destroyed rapidly by 5 or 10 ppm chlorine.