Prevalence and potential for aflatoxin contamination in groundnuts and peanut butter from farmers and traders in Nairobi and Nyanza provinces of Kenya

Abstract

Objective: Most of the peanut butter marketed in Nairobi is processed in cottage industry and its aflatoxin contamination status has not been documented. This study was therefore conducted to determine the status of aflatoxin contamination in groundnuts and peanut butter in Nairobi and Nyanza. Methodology and results: Eighty two fresh samples comprising raw and roasted groundnuts and peanut butter were obtained from market outlets and cottage processors in Nairobi and Nyanza regions. The marketers and processors were asked for information on the source of groundnuts. The incidence of Aspergillus section Flavi was determined using standard laboratory methods. Defective nuts in raw groundnuts were determined by manual sorting. Aflatoxin analysis was done using competitive ELISA technique. Groundnuts in Nairobi were imported from Malawi while those Nyanza were grown in the region. The fungal species isolated from the samples were: Aspergillus flavus (L and S strains), A. parasiticus, A. niger, A. tamari, A. alliaceus, A. caeletus and Penicillium spp. The percentage of defective nuts among all unsorted groundnuts ranged from 0.0% to 26.3%. The mean percent defective nuts was higher for Nairobi samples than Nyanza. Aflatoxin levels in all samples ranged from 0 to 2377.1 µg/kg. The mean aflatoxin level was higher for raw samples from Nairobi than Nyanza. The source of groundnuts and defective nuts were positively associated with aflatoxin levels. Conclusions and application of findings: The source of groundnuts and presence of defective nuts were identified as the main factors influencing increased aflatoxin contamination in the cottage industry. Mechanisms for inspection and certification of imported groundnuts should be put in place accompanied by effective monitoring for compliance to set aflatoxins standards. All the market players should sort their groundnuts before selling or processing in order to reduce aflatoxin contamination of peanut butter.

Aflatoxin B1 levels in groundnut products from local markets in Zambia

“…Of the 18 samples tested, only 3 had detectable levels of aflatoxin, ranging from 7 to 620 μg/kg. In east Africa, Ndung'u et al (2013) tested 82 fresh and roasted samples from markets in Kenya located in Nyanza and Nairobi. They found that 43% of the samples were above Kenya's regulatory limit of 10 μg/kg.…”

“…They found that 43% of the samples were above Kenya's regulatory limit of 10 μg/kg. Ndung'u et al (2013) reported that groundnut kernels that was sorted had the highest proportion of samples (83%) with aflatoxin levels below 10 μg/kg. Therefore, they proposed that sorting should be made mandatory for the groundnut marketers with effective monitoring to ensure compliance and that punitive measures should be given to non-compliance.…”

Contamination of Groundnut in South‐Western Nigeria by Aflatoxigenic Fungi and Aflatoxins in Relation to Processing

“…Contamination of groundnut and groundnut-based products by aflatoxins has extensively been reported in tropical countries where this crop is largely cultivated (Gachomo et al 2004;Ogunsanwo et al 2004;Bankole et al 2005;Aliyu and Kutama 2007;Ngoko et al 2008;Mutegi et al 2009;Soler et al 2010;Ndung'u et al 2013;Nyirahakizimana et al 2013;Limbikani et al 2014), but only very few studies focused on both aflatoxigenic moulds and aflatoxins (Gachomo et al 2004;Aliyu and Kutama 2007;Ngoko et al 2008;Soler et al 2010;Ndung'u et al 2013;Nyirahakizimana et al 2013). In Nigeria, groundnut is mostly consumed in its processed form (e.g.…”

Monitoring of Aflatoxin contamination at market food chain in east java

“…the marketing sectors especially at retail level in traditional market; here the contamination was generally found to be the highest. This indicates that aflatoxin contaminated peanuts entered in the marketing chain, post-harvest contamination of aflatoxin build up due to poor storage conditions (Dharmaputra et al, 2003;Dharmaputra et al, 2004;Rahmianna et al, 2007;Ndung'u 2013).…”