Yam chip food subsector: hazardous practices and presence of aflatoxins in Benin

Abstract

A survey of the sanitary quality, particularly concerning aflatoxin contamination and practices of the dried yam chips food sub-sector was carried out in Benin. Producers and intermediaries of the yam chips food production sub-sector were interviewed and samples collected. Aflatoxin content was assessed by a biochemo-luminescence method on a total of 107 samples. Twenty-three per cent of the samples had aflatoxin contents over the 15 μg kg−1 CODEX standard value for total aflatoxin. Moisture content of whole tuber chips was around 20% when producers stopped drying after 3–6 days. Drying was thus not accomplished, but most producers were unaware of this problem. After storage for 7 months, mean moisture content was around 14%, but 41% of the samples stored in rooms had a moisture content over 15%, levels that are still favourable for mould growth. Most producers, wholesalers and retailers complained about storage problems and particularly about insect proliferation, but less than 15% mentioned mould growth as a problem. Mouldy chips are generally washed and dried again. Very rarely are mouldy chips discarded and lack of moulds is not a quality attribute for dried yam chips. Therefore, there is a risk of chronic exposure to aflatoxin for Beninese yam chips consumers.