Abstract

Aflatoxins are potent mycotoxins classified as Group 1 human carcinogens and remain a significant food safety concern due to their acute toxicity and chronic health effects. Maize and maize-derived products are particularly susceptible to aflatoxin contamination, especially under conditions favorable for fungal growth during storage and processing. This study evaluated the effectiveness of garlic (Allium sativum) and ginger (Zingiber officinale) powders in reducing aflatoxin concentrations during maize malting and assessed their impact on the sensory acceptability of Thobwa, a traditional maize-based beverage. Mould-free maize samples were treated with 2 g garlic or ginger powder and then subjected to malting. Following malting, malted maize was ground into flour using Romer Labs Series II ® mill and then aflatoxin concentrations were determined in the resulting malt flour using a fluorometric method prior to beverage preparation. Sensory differences between Thobwa produced from treated and untreated malt were evaluated using a tetrad discrimination test. Both botanical treatments significantly reduced aflatoxin concentrations in malted maize compared with the untreated control. Garlic treatment reduced aflatoxin levels from 87.83 µg/kg in the control to 6.77 µg/kg, representing a 92.3% reduction, while ginger treatment reduced concentrations to 5.95 µg/kg, corresponding to a 93.2% reduction. Sensory evaluation indicated no significant differences (p > 0.05) between beverages prepared from treated and untreated malt, suggesting that the herbal treatments did not adversely affect product sensory characteristics. The findings demonstrate that garlic and ginger powders can substantially reduce aflatoxin contamination during maize malting without compromising the sensory quality of Thobwa. These readily available botanical materials offer a practical, low-cost, and consumer-acceptable intervention for mitigating aflatoxin exposure in maize-based foods and beverages, particularly in resource-limited settings.

Publication status

Published - 2026