Toxin Production by Clostridium botulinum in Shelf-Stable Pasteurized Process Cheese Spreads

Abstract

Five non-refrigerated, pasteurized process cheese spreads, considered shelf-stable, were studied for their ability to support growth and toxin production by spores of Clostridium botulinum types A and B. Based on pH and water activity (aw) Cheese with Bacon, Limburger, Cheese Whiz, Old English, and Roka Blue cheese spreads were selected for the study. The pH ranged from 5.05 to 6.32 and the aw from 0.930 to 0.953. Fifty jars of each cheese spread were inoculated with 24,000 spores each; an additional 50 jars of the Cheese with Bacon spread received 460 spores each. The inoculum consisted of five type A and five type B strains in 0.1 ml of 0.85% NaCl. At 35 C, 46 jars of Limburger and 48 jars of Cheese with Bacon spread, which received the greater inoculum, became toxic starting at 83 and 50 days, respectively. One jar of Cheese with Bacon spread which received 460 spores became toxic. The average toxicity of the Limburger was 3000 MLD/ml of extract as compared with 54 MLD/ml for the Cheese with Bacon spread. Results of this study will be considered in determining whether these cheese spread products should be treated as low-acid canned foods under the Good Manufacturing Practice Regulations of the Food and Drug Administration.

Process Cheese: Scientific and Technological Aspects—A Review

“…and postpasteurization pathogenic bacteria such as Listeria monocytogenes , Salmonella spp., Staphylococcus aureus , and E. coli O157:H7 (Glass and Doyle 2005). Research has indicated that the most common microorganisms associated with process cheese are of the genus Clostridium (Kautter and others 1979; Sinha and Sinha 1988; Glass and Doyle 2005). A few outbreaks involving botulism from the consumption of canned PCS have been reported over the years (Glass and Doyle 2005).…”

Fate of Clostridium sporogenes PA 3679 in Fish Sausage Formulations with Adjusted aw using Food Binders

“…The a, of these products ranges from 0.930 to 0.953 and the pH from 5.0 to 6.3 (Kautter et al, 1979). They have been consumed for many decades with no incidence of botulism attributed to them (Sperber, 1982).…”

“…S., pasteurized process cheese spreads (e.g., cheese with bacon, Limburger, Cheez Whiz@, Old English@, Roka Blue'@) are traditional examples. The a, of these products ranges from 0.930 to 0.953 and the pH from 5.0 to 6.3 (Kautter et al, 1979). They have been consumed for many decades with no incidence of botulism attributed to them (Sperber, 1982).…”

“…They have been consumed for many decades with no incidence of botulism attributed to them (Sperber, 1982). Studies on toxin formation by C. botulinurn, types A & B, in retail samples of these products by Kautter et al (1979) indicated some botulinal risk, but Tanaka et al (1979) using laboratory prepared cheese spreads showed otherwise. Summer sausages and country cured hams which are being retailed on unrefrigerated shelves in the U.S. could also be classified as SSPs.…”

Estabilidade de requeijão cremoso em diferentes embalagens com e sem exposição a luz

“…Os Além destes dois fatores, pode-se citar também o efeito protetor contra esporulados que os polifosfatos conferem ao requeijão, fato enfatizado por diversos autores em trabalhos publicados sobre o assunto (BERGER et al, 1997b;BRIOZZO et al, 1983;ECKNER et al, 1994;KAUTTER et al, 1979;KAUTTER et al, 1981;TANAKA et al, 1986).…”