**2.11 Aflatoxin management**

Common species of the soil-dwelling fungus *Aspergillus flavus* infest farmers' crops and foods, producing a highly toxic, cancer-causing poison called "aflatoxin" [59]. Widespread and severe contamination of several key staple crops, animal feeds, and processed foods occurs across Africa as a combined result of conducive weather conditions, extremely potent fungal strains, and substandard post-harvest handling and storage practices. In Africa, aflatoxin occurs not only in maize (**Figure 11**) and groundnut, where it poses a serious public health challenge, but also in cassava, sorghum, rice, and cashews, among others. When contaminated food is consumed by humans or livestock, aflatoxin accumulates inside the body and causes major damage to internal organs and blood. This toxin causes liver cancer, weakens people against other diseases, and stunts growth of children. Animals such as cows, pigs, and chickens are also affected by this toxin, and their milk, meat, and eggs become contaminated and unsafe for consumption. The aflatoxin pandemic in Africa has massive economic impacts by making food unfit to eat or trade, robbing humans of their health, and stunting and killing farm animals.

Biocontrol technologies for aflatoxin exist that rely upon natural competitors rather than industrial chemicals. These agents were safely and effectively adopted on increasingly large farmland areas over the past decade [60]. Aflasafe® is a product made in Africa that substantially reduces aflatoxin levels in food and is inexpensive and cost-effective to purchase and apply (**Figure 12**). The active ingredients of Aflasafe® are atoxic strains of *A. flavus* that do not produce the toxin. Combinations of four different strains are combined for each country by screening thousands of candidate strains recovered from local environments. Aflasafe® products are broadcast across crops 2 to 3 weeks before the onset of flowering. Alternatively, the product

**Figure 11.** *Infestation by* A. flavus *causing maize to be unfit for consumption.*

may be applied onto the soil using a tractor-mounted spinner [61]. Different Aflasafe® products are produced and marketed in Burkina Faso, Ghana, Kenya, Malawi, Mozambique, Nigeria, Senegal, Tanzania, The Gambia, Uganda, and Zambia. Additional countries are in the process of identifying and registering biocontrol agents and constructing production facilities. Manufacturers of biological control technologies for aflatoxin must gain approval to use certified strains of atoxic fungi and comply with national regulations concerning the production, distribution, and release of microbial agents. Farmers do not require permits to apply Aflasafe® to their fields. The atoxic strains of *A. flavus* used in biocontrol are never copyrighted. However, they remain the genetic resources and property of the countries where they are developed for use as a public good. The IITA Business Incubation Platform is responsible for further developing and extending Aflasafe® across Sub-Saharan Africa.

#### **2.12 Post-harvest management technologies**

In Africa, post-harvest management technologies for maize focus on reducing losses and maintaining grain quality. These technologies include drying methods such as solar and mechanical dryers and improved traditional drying techniques. Storage precautions such as hermetic bags, metal silos, and plastic drums are utilized to protect maize from pests and moisture. Grain cleaning using mechanical grain cleaners or sieves helps remove impurities. Maize processing technologies, such as milling machines and dehullers, are employed to transform maize into different products. Integrated pest management techniques and quality testing tools ensure pest control and quality assurance. These technologies minimize post-harvest losses and improve the value of maize crops.

Hermetic bags are a type of storage technology with a three-layered design. The outer layer is made of woven polypropylene and provides the necessary strength to support the weight of the stored grain (**Figure 13**). Inside, there are two inner bags made of high-density polythene. These inner bags are specifically designed to have extremely low gas permeability and are water-resistant. The production process of

*Agricultural Transformation in Maize Producing Areas of Africa DOI: http://dx.doi.org/10.5772/intechopen.112861*

**Figure 13.** *Many different brands of hermetic grain storage bags are now available through agrodealers.*

hermetic bags involves converting melted polypropylene into string form, which is then wound to create the polypropylene woven outer bag. A knitting machine weaves the string into the desired bag shape. For the polyethylene inner liners, recycled or raw plastic is melted and shaped into a thin layer, which is then cooled. The plastic is then combined into rolls and cut into the appropriate sizes for the inner bags. The purpose of hermetic bags is to create a barrier that prevents air and moisture from entering the stored grain. By cutting off the supply of oxygen, these bags effectively eliminate insects and microbial organisms, thus preserving the quality of the grain and reducing stored grain losses. They can provide storage for up to 2 years. Additionally, hermetic bags have gained cultural acceptance and are widely adopted by African farmers [62, 63].

Promoting hermetic bags prevents food loss and offers economic benefits to farmers and improved health outcomes due to reduced pesticide use and potential aflatoxin intake reduction. A study by Ndengwa et al. [64] found that compared to conventional methods, hermetic bags significantly curbed insect-related damage and weight loss with only 4% grain damage and 0.4% weight loss compared to the traditional practices group's 14% damage and 1.7% loss, over a crucial four-month storage period. The study also highlighted the potential profitability of hermetic bags with at least 4 months'seasonal usage across four seasons. Similarly, when produce quality is less crucial for a farmer's consumption, Dijkink et al. [65] reported that utilizing hermetic bags becomes economically advantageous compared to alternative storage methods for produce stored for more than 100 days.
