Effect of pH and CO2 on Growth and Toxin Production by Clostridium botulinum in English-Style Crumpets Packaged under Modified Atmospheres
Abstract:The effect of pH and CO2 on both growth of and toxin production by Clostridium botulinum in English-style crumpets, packaged under modified atmospheres was investigated using a 2 × 2 factorial experiment. English-style crumpets (water activity, 0.990; pH 6.5 and 8.3) were inoculated with C. botulinum spores types A and proteolytic B (500 spores/g), packaged in either 60% CO2 (balance N2 ) or 100% CO2, stored at ambient temperature (25°C), and monitored daily for toxicity. Toxin was detected after 4 days in crumpets packaged in 60% CO2, irrespective of initial product pH. Toxin production was delayed 1.5 to 3 days in crumpets packaged under 100% CO2. Analysis of variance indicated a significant interaction effect of pH and %CO2 on time of earliest toxin detection. Delay of toxin production was greatest for high pH (8.3) crumpets. All products were organoleptically acceptable at the time of toxigenesis, and therefore, high moisture–high pH bakery products, if contaminated with spores of C. botulinum, could become hazardous if packaged in atmospheres containing CO2.
Document Type: Research Article
Affiliations: 1: Department of Food Science and Agricultural Chemistry, McGill University, Macdonald Campus, 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec, Canada H9X 3V9 2: Bureau of Microbial Hazards, Food Directorate, Health Protection Branch, Health Canada, Ottawa, Ontario, Canada K1A 0L2
Publication date: October 1, 1999
- IAFP Members with personal subscriptions to JFP Online: To access full-text JFP or JMFT articles, you must sign-in in the upper-right corner using your Ingenta sign-in details (your IAFP Member Login does not apply to this website). The Journal of Food Protection (JFP) is a refereed monthly publication. Each issue contains scientific research and authoritative review articles reporting on a variety of topics in food science pertaining to food safety and quality. The Journal is internationally recognized as the leading publication in the field of food microbiology with a readership exceeding 11,000 scientists from 70 countries. The Journal of Food Protection is indexed in Index Medicus, Current Contents, BIOSIS, PubMed, Medline, and many others.
Print and online subscriptions are available to IAFP Members and institutional subscribers. IAFP Members with a subscription to JFP Online will have access to all available JFP and JMFT content. Online visitors who are not IAFP Members or journal subscribers will be charged on a pay-per-view basis. Membership and subscription information is available at www.foodprotection.org.
- Information for Authors
- Submit a Paper
- Subscribe to this Title
- Membership Information
- Information for Advertisers
- ingentaconnect is not responsible for the content or availability of external websites