High-temperature drying of organically grown bread rye

Summary

Mycotoxin producing fungi are naturally occurring components in cereals. When produced, some of the mycotoxins are toxic to humans and animals. Heat treatment is a method to reduce fungal abundance on cereals. The objectives of this work have been to provide more knowledge on this topic, and specifically to optimise the drum drying technique with reference to reducing the dissemination and proliferation of fungi on organically grown rye without reducing the baking quality of the grain.
The results show that drum drying can be a very efficient method in reducing fungi colonising on grain. For rye it is possible to achieve high effects on fungi without reducing the baking abilities. When drying at a constant maximum grain temperature of 64°C, the treatment resulted in less than 1% of the yeast propagules and less than 2% of the filamentous fungi, compared to what was found in the reference grain.
As drying temperatures and time for the grain to be treated are essential, the drum drier must be equipped with an effective control unit. The experiments show that a control system using fixed constant maximum grain temperature is most suitable.