The aim of the master's thesis was to investigate the influence of temperature and time on the formation of aflatoxin B1 (AFB1) and B2 (AFB2) in buckwheat contaminated with Aspergillus flavus during germination. In addition, we investigated the influence of different methods of heat treatment of buckwheat on the number of indigenous moulds, germination rate and sprout length as well as the influence of mechanical treatment (milling and hulling) on the number of moulds. Buckwheat was heat-treated at two different temperatures (60 and 80 °C) and with five different methods (dry/open, dry/closed, 1× moistened, daily moistened and prolonged treatment). The highest germination rate and sprout length was achieved with the dry/open method at 60 °C. Complete inhibition of mould growth was achieved with the procedures: 1× humidified, daily humidified and extended treatment, but in most cases no germination occurred with these procedures. This shows that the combination of heat treatment and moistening of buckwheat can reduce the number of moulds, but this combination also has a negative effect on buckwheat germination. Buckwheat hulling reduced the number of moulds, and a higher number of moulds was found in ground buckwheat than in whole buckwheat. The results of our investigations also showed that higher temperatures during prolonged buckwheat germination promote the formation of AFB1 and AFB2. The highest AFB1 concentration was detected in samples germinated at 21 °C for 7 days (24.32 ± 2,36 μg/g), while the highest AFB2 concentration was detected in samples germinated at 18 °C for 10 days (2.93 ± 0,82 μg/g). A lower temperature during a shorter germination period, which limits the formation of aflatoxins, has a negative effect on the conversion of macronutrients and the accumulation of secondary metabolites, which is why edible seeds are germinated in the first place.
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