**2.2 Heating treatment**

*Aflatoxin B1 Occurrence, Detection and Toxicological Effects*

rainbow trouts [6].

impose a great risk to the consumers.

update some new methods.

**2.1 Cleaning and segregation of aflatoxins**

aflatoxin risk.

upon the living organisms of aflatoxin decreases in an order B1, G1, B2, and G2 [5]. AFB1 is the most potent carcinogenic agent associated with hepatocellular carcinoma (HCC), one of the most lethal and common cancers in the world, especially in Asia and Africa. The mycotoxin aflatoxin B1 (AFB1), the most notorious liver carcinogen, has been proven to be genotoxic. Epidemiological studies have shown that chronic exposure to aflatoxin B1 in the diet is one of the important factors in the etiology of liver cancer in experimental animal models, including rats and

Discovery of practical and economical procedure to prevent aflatoxin contamination, detect and degrade *Aspergillus* fungi contamination, and lower the concentration of AFB1 in the foodstuffs is of the primary task to prevent or eliminate the

*Aspergillus* fungi is ubiquitously found in the soil and contaminates the crops in the field and during storage, such as maize, groundnuts, rice, and so on. Mycotoxins are the low-molecular weight nature products as the secondary metabolites of molds that make the industrial factories lose money resulting from condemnation of contaminated crops. They have been detected in various commodities such as maize, wheat, barley, oilseed, peanut, and beverages made from contaminated grains and other foods. Thus direct exposure to aflatoxin-contaminated commodities may

Unquestionably, prevention is the best method to control mycotoxin contamination. As the result of the high prevalence of AFB1 in the foods, many strategies are being developed to prevent or remove AFB1 contamination. In general, two ways are available to prevent AFB1 from contamination: pre- and postharvest treatment. Pre-harvest techniques are the first barrier to prevent mycotoxin contamination in all kinds of grains or feed. Pre-harvest techniques include the use of genetically altered crops that are resistant to *Aspergillus* infection and environmental stressors, pesticide usage, crop rotation, and timing of planting. Postharvest strategies include physical methods (proper drying, packaging, storage, preservative/pesticide usage). These strategies play the roles as the preventative measures to reduce the chance and the amount of contaminations that are introduced to the crops. However, these strategies fail to prevent the contaminations fully and effectively; thus some postharvest techniques are being developed to degrade or reduce AFB1 contamination. In this review, we aimed to investigate AFB1 decontamination methods, including several traditional strategies, and

**2. Physical treatment of aflatoxin removal and detoxification**

The first option to reduce aflatoxin is to physically separate the mold-contaminated grains or feed (kernel, seeds, and nuts) from the intact and apparently uncontaminated product. The physical procedure is the safe way not to alter the products significantly, including cleaning, sorting, and handpicking [7]. In the developing countries or economically underdeveloped areas, the people have little or no access to do mycotoxin testing of their foods. Hand sorting is still the primary method to remove AFB1. As compared with other methods including flotation and dehulling of the grains, hand sorting of maize grains boasts <6% of AFB1 and <5% of fumonisin B1. Thus hand sorting of maize grains is being recommended as a last line of defense against mycotoxin exposure among subsistence

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consumers [8].

Aflatoxins are well known to be stable at high temperature. In modern food/feed manufacturing technology, heating treatment is always used to degrade mycotoxins to a certain extent during the processing. Recent studies have shown that AFB1 could be significantly removed at high humidity [9–12]. However, several possible facts are associated with the prediction of the extent of mycotoxin reduction, such as initial mycotoxin concentration, the extent of binding between mycotoxin and food or feed products, heat penetration, moisture content, and processing conditions. Nonetheless, heat treatment to partially reduce the mycotoxin concentration in the food/feed stuffs is still the feasible physiological method because heating technique can be carried out easily at low cost. Extrusion cooking is broadly used in the field of food industry, which is an efficient process in food/feed process. High temperature with short-time extrusion is commonly used in the industry [5].
