Microbial Contaminants in Foods Prepared by Vacuum-Packed Pouch Cooking (Sons-Vide)

Abstract

Vacuum-packed pouch cooking (sous-vide) is now a wide-spread cooking method in hote restaurants. We have conducted microbiological studies on 39 items prepared by a hotel restaurant using this processing method. The following results were obtained; 1) In protein foods such as meat and fish, standard plate counts (SPC) were reduced to about 1/1000 by heat treatment between 58°C and 68°C employed in vacuum-packed pouch cooking. In most of the cooked samples, SPC were further reduced during 7 days at 0°C. 2) Psychrotrophic bacteria, coliforms and E. coli were undetectable in foods prepared by the technique of sous-vide. 3) Clostridium perfringens was found in cooked chicken breast meat and guinea fowl confie, but the number of anaerobes detected in both samples was below the limit imposed by Japanese law on meat products.