The methods of the International Office of Cocoa and Chocolate and International Sugar Confectionery Manufacturers' Association (IOCC/ISCMA), and of the Health Protection Branch (HPB) were compared for their ability to detect Salmonella in chocolate and cocoa products. Of 152 samples tested, 13 contaminated samples were identified, 10 by the HPB and 8 by the IOCC/ISCMA method. Prolonged (48 h) incubation of enrichment media produced two false-negative results each with the Muller-Kauffman tetrathionate and the selenite cystine broths, exerted no effect on tetrathionate brilliant green, and identified one additional positive sample with the selenite brilliant green broth. More samples were found positive on bismuth sulfite than on brilliant green and brilliant green sulfa agar media. The present study underlines the limited sensitivity of both standard methods and questions the determinant role of casein in the neutralization of toxic agents in cocoa products.

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