Aflatoxigenic fungi and aflatoxin in cocoa

This paper reports the occurrence of aflatoxigenic fungi and the presence of aflatoxins in 226 cocoa samples collected on Brazilian farms. The samples were taken at various stages of fermentation, drying and storage. A total of 819 potentially aflatoxigenic fungi were isolated using Dichloran 18% Gl...

ver descrição completa

Detalhes bibliográficos
Autor: Copetti, Marina V.; et al.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2011
País:Brasil
Recursos:Instituto de Tecnologia de Alimentos (ITAL)
Repositorio:Repositório do Instituto de Tecnologia de Alimentos
Idioma:inglés
OAI Identifier:oai:http://repositorio.ital.sp.gov.br:123456789/602
Acesso em linha:http://repositorio.ital.sp.gov.br/jspui/handle/123456789/602
Access Level:acceso abierto
Palavra-chave:Aflatoxin
HPLC
Aflatoxigenic fungi
Theobroma cacao
Aspergillus flavus
Aspergillus parasiticus
Chocolate
Descrição
Resumo:This paper reports the occurrence of aflatoxigenic fungi and the presence of aflatoxins in 226 cocoa samples collected on Brazilian farms. The samples were taken at various stages of fermentation, drying and storage. A total of 819 potentially aflatoxigenic fungi were isolated using Dichloran 18% Glycerol agar after surface disinfection, and identified by standard techniques. The ability of the fungi to produce aflatoxins was determined using the agar plug technique and TLC. The presence of aflatoxins in cocoa samples was determined by HPLC using post-column derivatization with bromide after immunoaffinity column clean up. The aflatoxigenic fungi isolated were Aspergillus flavus, A. parasiticus and A. nomius. A considerable increase in numbers of these species was observed during drying and storage. In spite of the high prevalence of aflatoxigenic fungi, only low levels of aflatoxin were found in the cocoa samples, suggesting the existence of limiting factors to the accumulation of aflatoxins in the beans.