Technical enzyme products have been used in the process of making fruit juices since the 1930's. They were originally used for clarifying and depectinising juices; at the start of the 1970's, they were used for mash enzyme treatment of apples. The pectolytic enzymes which are normally used feature polygalactonasis as their main activity and pectinesterasis as their secondary activity. In addition, they can also feature amylase, cellulase and protease activities. Pectolytic mash enzymes primarily hydrolyse the somewhat less esterified pectins of the membranes. Mash enzyme treatment is used for accelerating the juicing process in conjunction with higher yields. In particular, ripe apples which are usually very soft are very difficult to press and juice economically without the use of enzymes.

The necessary technical equipment for mash enzyme treatment consists of a unit for controlling the temperature of the mash, an enzyme adding unit and a dwell tank for the enzyme reactions. The activities of the enzymes which are used, the dwell time and the temperature are parameters which have an effect on yield and quality.

The combined use of pectinases and cellulases enable the mash to liquefy. The sugar content in the juice and the yield increase significantly due to the complete hydrolysis of sacchariferous macromolecules. However, the process of mash liquefaction is legally permitted only in certain countries.

Enzyme-treated apple mash can be juiced particularly well by means of decanters. The reduction in viscosity due to the action of enzymes and the simultaneously higher temperature leads to higher throughputs and better degrees of clarification in the production of juices. However, it is very difficult to make cloudy juices by means of mash enzyme treatment.