The fungus is grown in continually oxygenated water in large, otherwise sterile fermentation tanks. Glucose and fixed nitrogen are added as a food for the fungus, as are vitamins and minerals to improve the food value of the product. The resulting mycoprotein is then extracted and heat-treated to remove excess levels of RNA. Previous attempts to produce such fermented protein foodstuffs were thwarted by excessive levels of DNA or RNA; without the heat treatment, purines, found in nucleic acids, are metabolised by humans to produce uric acid, which can lead to gout.