Fusarium venenatum. A3/5 was first chosen for development as a myco-protein in the late 1960s. It was intended as a protein source for humans and after 12 years of intensive testing, F venenatum A3/5 was approved for sale as food by the Ministry of Agriculture, Fisheries and Food in the United Kingdom in 1984. Today, myco-protein is produced in two 150,000 1 pressure-cycle fermenters in a continuous process which outputs around 300 kg biomass/h. The continuous process is typically operated for around 1,000 h. One factor which has limited the length of production runs was the appearance of highly branched mutants in the population. Several factors affect the time of appearance of such mutants and a number of strategies for delaying their appearance have been investigated. After reduction of the RNA content, the fungal biomass is mixed with egg albumin and made into a variety of products. Consumption of these can lead to reduced blood cholesterol and to lower energy intake in a subsequent meal. F. venenatum myco-protein is now used in products available in six European countries and there are plans for it to be sold in France, the United States and Germany.