Abstract

Peanut seeds (Arachis hypogaea L.) are consumed worldwide including Mozambique, due to good taste, high nutritional value and easy accessibility. When found in suitable conditions of humidity and high temperature, a fungus of the genus Aspergillus can contaminate peanuts and produce toxic secondary metabolites called "aflatoxins" (AFs) which are not destroyed by usual thermal processes, causing aflatoxicosis and liver cancer, when consumed frequently. This study aimed to identify the concentration of aflatoxins B1 (AFB1) in raw peanuts seeds marketed in Maputo city and to analyze the association with the storage conditions. Raw peanuts samples of 1 kg were acquired in 57 commercial establishments in Maputo city (63.16% markets and 36.84% supermarkets).  AFB1 concentration was analyzed by ELISA test. Peanut storage conditions were analyzed in each sampling spot. The results of the study showed that the average concentration of AFB1 on peanut was 2.71 µg/kg (0.00 to 72.93). The prevalence of AFB1 above the limit of European Union (EU) legislation (8 µg/kg) was 3.5%. The significantly associated factors (p<0.05) were: Mozambican origin, presence of damaged kernels, storage time over 15 days and container where the peanut was stored. Most factors were associated with poor storage and measures should be taken to avoid the presence of these chemicals in peanuts. In conclusion, the concentration of AFB1 in raw peanuts seeds was within the acceptable European Union (EU) standards at 96.49%. Similar studies should be made in the country to identity the concentration of these compounds and probable sources of contamination.

Key words: Aflatoxin B1, peanut, markets, supermarkets, Maputo, Mozambique.