Detoxification of aflatoxin B1 in peanut meal by heating and gamma irradiation

Thesis Type: Doctorate

Institution Of The Thesis: Middle East Technical University, Faculty of Engineering, Department of Food Engineering, Turkey

Approval Date: 2015

Thesis Language: English


Principal Supervisor (For Co-Supervisor Theses): Faruk Bozoğlu

Co-Supervisor: İlkay Şensoy


Aflatoxin is one type of mycotoxin, which is synthesized by some molds as by-products under certain conditions and needed to be controlled because of several health risks when present in foods and feeds. Due to these health related effects, prevention of aflatoxin in food and feed is essential. According to the Turkish Food Codex Communiqué on Undesirable Substances in Feed, the maximum limit of aflatoxin B1 in feed materials is defined as 0.02 ppm. In case of unavoidable aflatoxin contamination, there are variety of techniques for detoxification of aflatoxins such as fermentation, extraction, extrusion, solar treatment, oxidizing agents and gamma irradiation. In the scope of this thesis, naturally aflatoxin contaminated peanut meal were subjected to different treatments (roasting (120°C, 160°C and 200°C) and gamma irradiation (10 kGy)) in order to reduce Aflatoxin B1 content to the levels specified by Food Codex. Studies on residual toxicity after treatments were also carried out to test whether the toxicity increases due to by products formed upon treatments. According to the results obtained from our experiments; high temperature roasting (200°C) and gamma irradiation (10 kGy) were more effective on aflatoxin B1 reduction (~80%). Roasting especially at high temperatures (200°C) and gamma irradiation reduced the level of protein content of peanut meal samples. Minimum reduction in the protein content was observed in samples treated with gamma irradiation. In addition to the reduction levels, used techniques did not have an increasing effect on toxicity of Aflatoxin B1.