Evaluation of an alternative extraction procedure for enterotoxin determination in dairy products.
A concentration protocol based on trichloroacetic acid precipitation was evaluated and compared with the reference method using dialysis concentration. Different quantities of purified staphylococcal enterotoxins were added to pasteurized Camembert-type cheeses. Detection of enterotoxins in these cheeses was performed using an automated detection system. Raw goat milk Camembert-type cheeses involved in a staphylococcal food poisoning were also tested. Both enterotoxin extraction methods allowed detection of the lowest enterotoxin concentration level used in this study (0.5 ng g-1). Compared with the dialysis concentration method, TCA precipitation of staphylococcal enterotoxins was 'user-friendly' and less time-consuming. These results suggest that TCA precipitation is a rapid (1 h), simple and reliable method of extracting enterotoxin from food which gives excellent recovery from dairy products.
Meyrand
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A
Unité de Microbiologie Alimentaire et Prévisionnelle, Ecole Nationale Vétérinaire de Lyon, France. hidaoa@vet-lyon.fr
Atrache
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V
Bavai
C
C
Montet
M P
MP
Vernozy-Rozand
C
C
D000818:Animals; D002611:Cheese / Q000032:analysis* / Q000382:microbiology*; D011232:Chemical Precipitation; D003956:Dialysis / Q000379:methods; D004768:Enterotoxins / Q000302:isolation & purification*; D013202:Staphylococcal Food Poisoning / Q000382:microbiology*; D013211:Staphylococcus aureus / Q000737:chemistry* / Q000302:isolation & purification; D014238:Trichloroacetic Acid
D004768:Enterotoxins; D014238:Trichloroacetic Acid