Factors Influencing Growth and Toxin Production in Cheese Inoculated with Spores of Clostridium Botulinum Types A and B. II. Studies with Surface-Ripened Cheese Type II

Abstract

Studies were conducted to determine the maximum brine concentrations Clostridium botulinum Types A and B would tolerate ceasing growth and toxin production in heated surface mold-ripened cheese designated Type II. Type II cheese with added stabilizer and initial pH levels of 5.7 or below was a poorer medium than similar preparations with pH levels above 5.7, but was an equally good medium for growth and toxin production of C. botulinum when the pH was adjusted upward with NaOH solution. Growth and toxin production occurred in cheese with brine concentrations up to more than 7.0% when Type A spores were used; with Type B spores, the maximum brine concentrations tolerated were near 6.0%.