Determining aflatoxins contamination in locally processed peanut butter using fluorometry and hplc in Arusha city, Tanzania

A Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Masters in Life Science and Bioengineering of the Nelson Mandela African Institution of Science and TechnologyFood poisoning with mycotoxins produced by fungi is a global food safety issue. The consumption of mycotoxin-contaminated foods is responsible for several foodborne diseases outbreak worldwide. While peanuts are an important crop with both economic and nutritional significance in tropical and subtropical regions, their vulnerability to aflatoxin contamination, for example, makes them unsuitable for human consumption. This study aimed at assessing the aflatoxin contamination of locally processed peanut butter in Arusha city. Fifty samples of peanut butter from ten different firms (5 different batches per firm) were purchased at the local markets, supermarkets, and retail shops in the city. High-Performance Liquid Chromatography and Vicam fluorometer methods were used for aflatoxin analysis in the samples. Whereas the total amount of aflatoxins detected by Vicam fluorometer ranged from 5.6 to 720 ppb (μg/kg), by High-Performance Liquid Chromatography it ranged from 1 to 1981.37 μg/kg. These results showed a moderate positive correlation or relationship between High-Performance Liquid Chromatography and Vicam Fluorometer methods with r = 0.47. This implies that Vicam fluorometer can be more effective in initial determination of aflatoxins prior to food processing. The results further suggest that unhygienic processing practices, poor quality raw materials used for food processing, and the lack of quality control in local production chains might be the source of high aflatoxins contamination in peanut butter. Accordingly, a moderate positive correlation in total aflatoxin concentration was revealed between High-Performance Liquid Chromatography and Fluorimeter methods (r = 0.47). This indicates that Fluorimeter could be a suitable and cost-effective pre-screening tool of aflatoxin levels in locally processed food products. It is recommended that farmers and food processors in local production chains can use Vicam fluorometer to determine the quality of raw materials before processing foods intended for human consumption. This could help farmers and food processors to timely identify aflatoxin contamination of their raw materials and products at pre and post-processing stages, and hence, improving the quality and safety and product market value