Biomedical subjects

F Untermann

Publications and source records attributed to F Untermann.

18 recordsLinked to original sources

PubMed1992

Influence of aw value and storage temperature on the multiplication and enterotoxin formation of staphylococci in dry-cured raw hams.

Growth and enterotoxin A production in dry-cured raw ham, with different aw and pH values, was investigated for Staphylococcus aureus strain FRJ-100 over a temperature range of 20-35 degrees C when stored for up to 7 days. Enterotoxin production took place at all temperatures tested in the meat of ham that was cured, but not dried (aw 0.95). In dry-cured raw ham with an aw-value of about 0.92, and stored at 20 degrees C, no enterotoxin production was detectable within the 7-day storage period, whereas enterotoxin was produced at the higher temperatures. In ham with an aw of about 0.89, enterotoxin was produced only when stored for 7 days at 35 degrees C. Critical points for S. aureus multiplication and enterotoxin-formation during production and storage of dry-cured raw ham are discussed.

Animals↗

PubMed1991

The presence of enterotoxigenic Clostridium perfringens strains in faeces of various animals.

The presence of Clostridium perfringens in faeces of horses, cattle, poultry and pigs was determined. C. perfringens was detected in 24%, 36%, 80% and 2% of the faecal samples, respectively. Faecal samples containing enterotoxigenic strains as assessed by colony hybridization amounted to 14%, 22%, 10% and 0% respectively.

Animals↗

PubMed1990

Growth of pathogenic Yersinia enterocolitica strains in minced meat with and without protective gas with consideration of the competitive background flora.

The growth of two pathogenic Yersinia enterocolitica strains (O:3, O:9 at 1 degree C, 4 degrees C, 10 degrees C and 15 degrees C) in minced meat produced under sterile conditions and in minced meat with a normal background flora was investigated. In addition, the influence of treatment with a protective gas (20% CO2, 80% O2) was tested. In minced meat produced under sterile conditions and incubated under normal atmospheric conditions, Y. enterocolitica increased in numbers by only 1 log at 1 degree C and 3.5 logs at 4 degrees C within 14 days. At 10 and 15 degrees C, there was about a 5-log increase in cell numbers within 5 days. There was a marked inhibition of growth by the background flora on Y. enterocolitica. This effect was so marked that only a slight additional inhibition on the growth of Y. enterocolitica at 1, 4 and 10 degrees C was observed under the CO2:O2 modified atmosphere. This is in contrast to the situation where minced meat with a low total bacterial count was used, and the growth of Y. enterocolitica was adversely affected by the CO2:O2 environment. The significance of raw minced meat in the development of human Y. enterocolitica infections is also discussed.

Animals↗

PubMed1986