Abstract
In this study the methods of Hungate were used to quantitate the anaerobic bacteria present in commercially available ground beef, cheddar cheese, and German hand cheese. Of 235 anaerobic roll-tube isolates from ground beef and German hand cheese, all were facultative anaerobes. Of 213 anaerobic roll-tube isolates from cheddar cheese, 91% were facultative anaerobes and 9% were obligate anaerobes. Using results of biochemical tests, 14 or the 17 obligately anaerobic isolates from cheddar cheese were Propionibacterium acnes, two were strains of Propionibacterium that could not be speciated, and one was tentatively identified as a strain of Streptococcus evolutus. Obligate anaerobes were estimated to be present in the cheddar cheese at a level of about 10(6)/g. The possible significance of these levels of P. acnes in nonsterile foods is discussed.
Full text
PDF





Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Attebery H. R., Finegold S. M. Combined screw-cap and rubber-stopper closure for Hungate tubes (pre-reduced anaerobically sterilized roll tubes and liquid media). Appl Microbiol. 1969 Oct;18(4):558–561. doi: 10.1128/am.18.4.558-561.1969. [DOI] [PMC free article] [PubMed] [Google Scholar]
- LEDERBERG J., LEDERBERG E. M. Replica plating and indirect selection of bacterial mutants. J Bacteriol. 1952 Mar;63(3):399–406. doi: 10.1128/jb.63.3.399-406.1952. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Macy J. M., Snellen J. E., Hungate R. E. Use of syringe methods for anaerobiosis. Am J Clin Nutr. 1972 Dec;25(12):1318–1323. doi: 10.1093/ajcn/25.12.1318. [DOI] [PubMed] [Google Scholar]
- Pierson M. D., Payne S. L., Ades G. L. Heat injury and recovery of vegetative cells of Clostridium botulinum type E. Appl Microbiol. 1974 Feb;27(2):425–426. doi: 10.1128/am.27.2.425-426.1974. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pulverer G., Ko H. L. Fermentative and serological studies on Propionibacterium acnes. Appl Microbiol. 1973 Feb;25(2):222–229. doi: 10.1128/am.25.2.222-229.1973. [DOI] [PMC free article] [PubMed] [Google Scholar]