By By JAMES TABABA
Corn is a major crop in the Philippines, providing many people with food, feed, and income. However, the presence of aflatoxin poses a significant threat to both human health and the agricultural industry. Aflatoxin is a naturally occurring mycotoxin produced by certain molds, predominantly Aspergillus flavus and Aspergillus parasiticus. These molds thrive in warm and humid environments, making corn susceptible to contamination, especially during storage.
Aflatoxin in corn can originate from various sources, including pre-harvest contamination due to mold growth on the cob and post-harvest contamination during storage and transportation. It poses severe health risks to humans and animals alike.
Health risksÂ
Consumption of aflatoxin-contaminated corn can lead to acute and chronic health problems in humans. Acute aflatoxicosis can cause liver failure and even death, while long-term exposure may result in liver cancer, particularly in individuals with pre-existing liver conditions.
Aflatoxin-contaminated corn used in animal feed can lead to poor growth, reduced egg production, and compromised immune systems in livestock and poultry. This not only affects farmers’ income but also impacts the supply of meat, eggs, and dairy products.
The following farming practices recommendations are based on the standards of Good Agricultural Practice for corn set by the Department of Agriculture.
Recommended practices to minimize contamination
Implementing good agricultural practices, such as proper irrigation, pest control, and crop rotation, can reduce the risk of mold growth in corn fields. Furthermore, using high-quality seeds and following recommended planting practices can enhance resistance to aflatoxin contamination.
To prevent aflatoxin contamination during harvesting, it’s best to harvest on sunny days and avoid dehusking during rainy periods. Air-dry unhusked ears promptly in a well-ventilated area, and use clean containers for storage. Ensure harvesting machines are functional and clean to minimize grain damage. Discard corn ears with visible damage or infection properly in a compost pit away from the production area.
After harvesting, haul corn ears using clean and dry transport facilities to avoid contamination during transportation. Limit the piling duration of corn ears with husks to a maximum of three days, using underlay to prevent direct contact with the floor and clean matting materials.
Before shelling, dry corn grains to 18-20% moisture content, allowing them to withstand mechanical damage during shelling. Use well-maintained mechanical shellers to minimize kernel damage and prevent aflatoxin contamination. Store the shelled corn kernels in clean, dry containers, avoiding those previously used to contain chemicals or fertilizers. If immediate shelling isn’t possible, temporarily store the corn ears in well-ventilated cribs or structures to prevent heat build-up and microbial growth.
When drying, maintain the corn grains’ moisture content at 13 to 14% within 48 hours using calibrated moisture testers. Use mechanical dryers with air-drying temperatures between 43°C to 50°C to avoid stress cracks. When sun drying, protect the shelled corn from soil contact and prevent mixing with wet grain or foreign matter. Consider temporary storage in well-ventilated cribs if immediate drying isn’t feasible.
After drying, quickly move the bagged corn grains to suitable storage or processing areas to prevent aflatoxin growth. Cover the containers during transport to avoid re-wetting the grains and potential contamination. Stack the bags properly inside the transport vehicle to prevent damage.
For safe storage, use a durable structure with good ventilation situated in a flood-free area designed to prevent re-wetting and animal entry. Follow the first-in first-out principle for rotation. Keep the corn’s moisture content below 14% to prevent fungal growth. Regularly check the stored corn’s temperature for signs of microbial growth or pests. Keep the storage area clean to avoid pests and aflatoxin contamination. If mold is found, remove the affected parts and consider aflatoxin analysis for safety assurance.
The dangers of aflatoxin in corn pose a significant concern, as they have profound impacts on both human health and the agricultural sector. It is essential to implement preventive measures, including proper drying, storage, and monitoring, to safeguard the quality of corn and ensure the safety of food and feed products.
