Abstract
Every Penicillium camemberti strain freshly isolated from 20 commercial cheese brands produced cyclopiazonic acid in two culture media at 25, 13, and 4 degrees C; the toxin yield was greatly dependent on the strain and environmental parameters (medium, temperature, and incubation time). The toxigenic ability appeared as a log-normal distribution. This mycotoxin was found in the crust (0.05 to 0.1 microgram/g in three samples, 0.1 to 0.2 microgram/g in five samples, and 0.4, 1, and 1.5 microgram/g in three other samples) but not in the inner part. When its acute toxicity is considered, doses eventually ingested by consumers are very low (lower than 4 microgram). Means for prevention are discussed. A highly toxigenic strength and rate appear to be necessary features leading to natural contamination in cheeses. The distribution of toxigenic ability makes possible without delay a choice of weakly toxic strains.