Clostridium perfringens en carnes crudas y cocidas y su relación con el ambiente en Costa Rica / Clostridium perfringens in raw and cooked meats and its relation with the environment in Costa Rica

RESUMO

The presence of Clostridium perfringens in eight slaughter houses from Costa Rica was analyzed using the Most Probable Number (MPN) technique, in order to assess the risk of acquiring a food borne intoxication due to consumption of contaminated meat. C. perfringens was detected in 29 (88) out of 33 soil samples collected from the slaughter house surroundings (average 6.7 x 10(2) MPN/g), as well as in 70 (93) out of 75 intestinal contents of slaughtered animals (average 3 x 10(4) MPN/g), in 42 (55) out of 76 samples of slaughtered meat (average 2.2 x 10(4) MPN/g) and in 30 (61) out of 49 retail meats (average 8 x 10(3) MPN/g). In addition, the presence of this bacterium was evaluated in ten retail meat markets located in the Metropolitan Area of Costa Rica, where it was isolated from 15 (75) out of 20 samples of ground meat and from 28 (36) de 78 stew meat samples (average 1.9 x 10(3) and 7.5 x 10(2) MPN/g, respectively). Only one out of 35 samples of cooked meat obtained from 32 restaurants that utilize heated water baths (average temperature of 82 degrees C) was positive for C. perfringens (4 MPN/g, temperature 72 degrees C). Out of 1121 bacterial isolates obtained, 250 were evaluated for enterotoxigenicity. Only 3 (1.2) of these tested positive for enterotoxin production, probably because most wild strains are not toxin producers, even though they can be induced to produce it as a result of repeated thermal shocks. The present results urge the adoption of adequate preventive measures and high sanitary standards in the meat processing industry in Costa Rica, in order to minimize the risk of food-borne intoxications caused by C. perfringens, due to its widespread distribution and potential human health hazard.