Protease

Function

Protease is the collective name for various enzymes that break down or modify proteins or peptides (building blocks of proteins).

Proteases are produced naturally by many microbes; they also occur in many animals and plants.

• Animals produce digestive enzymes that break down proteins, such as trypsin, pepsin or chymosin.

• Some plants, such as pineapple, have a high protease content. The main enzyme of pineapple is called papain.

• Many foodstuffs (meat, cheese, fish) also contain proteases or activate them during the process of maturing. The "hanging" of meat activates digestive enzymes that tenderize the meat.

Application

Commercial protease preparations usually consist of a mixture of various protease enzymes. They are largely utilized in food processing:

• as a baking enzyme to improve the workability of dough – particularly in crackers and biscuits (bakery);

• in the extraction of seasonings und flavourings (cheese flavours) from vegetable or animal proteins (such as whey or milk proteins); in the manufacture of sauces (mainly: soya sauce) and yeast extract;

• to optimize and control the aroma formation in cheese and milk products;

• as flavour enhancers in savoury seasonings;

• to improve the texture of fish products, and in fish processing (such as in the production of filleted fish);

• to tenderize meat (not permitted in Germany) and in the manufacture of meat extracts;

• during cold stabilization of beer (in Germany, the purity law for beer prohibits the use of enzymes);

• particular proteases are also used for the production of hypoallergenic food . These proteases break down specific allergenic proteins that can cause allergic reactions in sensitized people. Proteases are utilized, for example, to produce hypoallergenic baby food from cow’s milk. The proteases break down milk proteins into small peptides and amino acids, thus diminishing the risk of babies developing milk allergies. 

Further applications:

• in detergents: proteases remove protein-containing stains

• in the leather industry, treatment of wool and raw silk

• as additives in pet food (better uptake of nutrition, due to the partial breakdown of proteins)

Gene technology

Proteases are produced in bacterial and fungal cultures through fermentation.

• There is a multitude of proteases available commercially. In Europe alone there are 40 protease preparations on the market.

• Fifteen of these protease preparations can be produced with genetically modified microorganisms (such as Aspergillus, Bacillus).

Labelling: labelling of enzymes in regard to their production using GM microorganisms is generally not foreseen in the European Union.