Pectinase

Function

Pectinase (also known as polygalacturonase) is the collective term for a row of enzymes that are able to break down or to transform pectins. Pectin is a substance which stabilises the cell walls of plant cells. Some fruits form pectinase during natural gestation.

See also: pectinesterase

Application

Often in combination with other enzymes, pectinases are used:

• foremost in the preparation of fruit juices and vegetable juices in order to increase the juice yield. Particularly in the case of berries, pectinases improve the extraction of colourings and aromas. In some cases, they clarify naturally cloudy juices. In the preparation of juices from berries, tropical fruits, apples and pears, the use of pectinase additives is common

• in the manufacture of concentrates made from fruit or vegetables (a carefully warmed mass made from uncooked plants or plant parts), such as in the case of tomatoes, onions, carrots, paprika and celery as well as plums, buckthorn and rosehips

• in the extraction of pigments and food colourings from plant-based raw materials

• in the extraction of highly concentrated citrus aromas from the zests of citrus fruits

• in "enzymatic peeling" of fruits (as in fruit salads, for example), in order to prepare fresh, peeled fruit

• in the manufacture of wine
  Pektinases facilitate the clearing of fresh-pressed wine must and improves its consistency. The fluidity of the wine is improved.

• in the industrial manufacture of feed (polygalacturonase and pektinlyase)

Gene technology

Pektinases primarily are obtained through fermentation with fungal cultures (Aspergillus, Penicillium and Trichoderma types).

• Several enzymes from the group of pectinases (for example, polygalacturonase and pektinlyase) are obtained with the aid of genetically modified moulds. Pectatlyase can be obtained with genetically modified bacteria (Bacillus), however is utilised only for technical industrial purposes.

• A variety of pektinesterases (enzymes that modify pectin) are produced with the aid of genetically modified moulds Aspergillus, Penicillium). These may be found in various pectinase preparations.

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