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Mycotoxins and Mycotoxigenic Fungi in Nepalese Chili
Nepal is among the countries that benefitted from the United States Agency for International Development (USAID), Feed the Future program, and Global Food Security Strategy which is dedicated to ending hunger and poverty worldwide. The Program’s goal is to achieve food security by transforming the food systems in beneficiary countries. Nepal is an agrarian society, with agriculture providing livelihood to 68% of the population and employing about two-thirds of the economically active population. Through this program, Nepal was able to increase the production of horticultural crops. Chili’s unique flavor, unique aroma, and rich taste are responsible for its increased global demand. Nepal’s chili production increased by almost four-fold from 2011 to 2020. However, chili is one of the spices susceptible to fungal contamination due to its production and processing conditions. The overarching objective of this study was to examine the factors that compromise chili quality and safety. This was achieved by assessing the mycobiota and the mycotoxin metabolites they produce, aflatoxin and ochratoxin, in chili samples from Nepal. High concentrations of these mycotoxins in foods are a public health risk given the acute and chronic illnesses they cause in humans. This study also assessed extrinsic factors, moisture content, and water activity that influence contamination. Despite the low moisture content and water activity, the presence of fungi, aflatoxin, and ochratoxin was still detected in the samples evaluated. Aflatoxin was found at relatively lower concentrations with a lower frequency of samples that exceeded the European Commission maximum allowable limit for this toxin. However, ochratoxin was found in higher levels which prompted further investigations associated with the stability of ochratoxin upon cooking (boiling) and the bioaccessibility of the ochratoxin in chili. The results revealed that ochratoxin A is stable in boiling temperatures up to 100 °C and that its bioaccessibility remains high after cooking. These results show that efforts to control contamination by fungus and mycotoxins must be conducted during preharvest and postharvest operations before the chili reaches the consumers.
Morrison, Donna Marcel, "Mycotoxins and Mycotoxigenic Fungi in Nepalese Chili" (2022). ETD collection for University of Nebraska - Lincoln. AAI29998901.