Phytase enzymes produced by bacteria or fungi can cleave inorganic phosphorus from the phytate molecule to increase the amount of bioavailable phosphorus in feed grains. By increasing grain phosphorus bioavailability, the amount of supplemental mineral phosphorus needed to balance the feed ration is reduced. Likewise, the amount of phosphorus released to the environment through fecal matter as unutilized phosphorus is also reduced.

Phytic acid is the major storage form of phosphorus in cereals, legumes and oilseeds. It serves several physiological functions and also significantly influences the functional and nutritional properties of cereals, legumes and oilseed (and food and feed derived thereof) by forming complexes with proteins and minerals. The salts of phytic acid are described as phytates. More accurately, phytate is a mixed potassium-, magnesium- and calcium salt of phytic acid that is present as a chelate in cereals, legumes and oilseed.

Adding phytase to animal feeds makes grain phosphorus more available to animals, thereby reducing the amount of supplemental phosphorus needed for optimum animal performance.