Comparison of iron milk and official AOAC methods for enumeration of Clostridium perfringens from fresh seafoods.

Fresh seafoods collected from Seattle area markets were evaluated for the presence and numbers of Clostridium perfringens. In a comparison of the official AOAC Shahidi-Ferguson perfringens and the simple iron milk methods, 29 of 287 samples of fresh fish and shellfish were positive for C. perfringens. All 29 positive samples were detected by the iron milk medium; however, only 7 of the 29 were detected by the AOAC methods. A statistical evaluation of the data showed a significant difference between the 2 methods.