Enzymes

How are the enzymes for processing organic foods produced and used?

By Nick Stansbury

Enzymes are proteins that act as catalysts and can increase the rates of chemical reactions. Enzymes can be sourced from plants, animals and microorganisms. Most commercially important enzymes are derived from microbial sources, with a smaller fraction derived from plant and animal tissues. The National Organic Program (NOP) regulations at §205.605(a) allow the use of animal enzymes (rennet – animal derived; catalase – bovine liver; animal lipase; pancreatin; pepsin; and trypsin) and enzymes derived from edible, nontoxic plants, nonpathogenic fungi or nonpathogenic bacteria. As products of biological processes, enzymes are generally considered nonsynthetic and allowed; however, the NOP regulations prohibit at §205.105(e) the use of methods to genetically modify organisms. OMRI reviews enzymes produced using GMO technology in accordance with the OMRI Generic Materials List© GMO Decision Trees.

Plant and animal enzymes are extracted from tissues and then often purified using a number of methods. For plant enzymes, the tissue is processed to break the cells and the enzyme is isolated, separated and purified by methods that may include chromatography, ultrafiltration, precipitation (using substances such as ethanol and ammonium sulfate), ion exchange and freeze-drying. Animal enzymes are extracted from various organs: rennet is derived from the abomasum (fourth stomach chamber) of ruminants; catalase from cow liver; lipases from the forestomachs of calves, goat kids or lambs, or from an animal pancreas; pancreatin and trypsin from a cow or pig pancreas; and pepsin from hog stomachs.

Microbial enzymes are usually produced by submerged fermentation and, to a lesser extent, solid state fermentation (important for certain fungal enzymes). The enzyme may remain in the microbial cell, requiring the destruction of the cells after fermentation to obtain the enzyme, or it is excreted into the culture medium. It is then isolated and purified by methods that may include filtration and centrifugation, the precipitation of nucleic acids, precipitation of the enzyme, liquid-liquid partition, ion exchange, and separation by chromatography. 

Enzymes, especially those in liquid enzyme formulations, are often formulated with synthetic materials such as preservatives. Preservatives, stabilizers, and carriers are reviewed by OMRI to confirm compliance to the organic regulations if they remain in the final enzyme product.   Production of enzymes from artificial genetic material was reported in 2014*. However, it does not appear that these synthetic enzymes are currently commercially produced.

Enzymes are used in a myriad of ways in food processing, including hydrolysis of starches, sugars and proteins, for tenderizing of meat, and in the production of beer, wine and cheese.

This article was originally published in the Winter 2018 edition of the OMRI Materials Review newsletter, and was updated in June 2020 by Technical Director Doug Currier.