Phytase for food application

Phytase [myo-inositol(1,2,3,4,5,6)hexakisphosphate phosphohydrolase], a phytate-specific phosphatase, is already used as a supplement in diets for monogastric animals to improve phosphate utilisation from phytate [myo-inositol(1,2,3,4,5,6)hexakisphosphate], the major storage form of phosphate in plant seeds. In recent years, this class of enzymes has also been found increasingly interesting for use in processing and manufacturing of food for human consumption, particularly because the decline in food phytate results in an enhancement of mineral bioavailability. Different strategies could be applied to optimise phytate degradation during food processing and digestion in the human alimentary tract such as adjustment of more favourable conditions during food processing for the phytases naturally occurring in the raw material, addition of isolated phytases to the production process, use of raw material with a high intrinsic phytate-degrading activity either naturally present or introduced by genetic engineering and the use of recombinant food-grade microorganisms as carriers for phytate-degrading activity in the human gastrointestinal tract. Furthermore, phytases may find application in the production of functional foods or food supplements with health benefits. Last but not least, technological improvements are expected to occur due to phytate degradation during processing as shown for breadmaking, production of plant protein isolates, corn wet milling and the fractionation of cereal bran.