Almost all foods have its source in plants. Many food is gained directly from plants; but even animals that are used as food sources are raised by feeding them food produced from plants. Cereal grain is a staple food which supplies more food energy worldwide than any other type of crop. Maize, wheat, and rice - in all of their varieties - account for 87% of all grain production worldwide.Most of the grain that is produced worldwide is fed to livestock.
Other foods not from animal or plant sources include various edible fungi, especially mushrooms. Fungi and ambient bacteria are used in the preparation of fermented and pickled foods like leavened bread, alcoholic drinks, cheese, pickles, kombucha, and yogurt. Another example is blue-green algae such as Spirulina. Inorganic substances such as baking soda and cream of tartar are also used to chemically alter an ingredient.