Mycoprotein, also known as fungal protein. A fungus called Fusarium venenatum is the main source of mycoprotein. The fungus is grown in vats using glucose syrup as food. A fermentation vat is filled with the growth medium, and then inoculated with the fungal spores. The Fusarium venenatum culture respires aerobically, so for it to grow at an optimum rate, it is supplied with oxygen, and carbon dioxide is drawn from the vat. To make protein, nitrogen (in the form of ammonia) is added, and vitamins and minerals are needed to support growth. The vat is kept at a constant temperature, also optimized for growth; the fungus can double its mass every five hours.