8 - Pectinases: Production and Applications for Fruit Juice Beverages

Abstract

Beverage industry for its fruit juice products and fruit softening has been using cell wall degrading enzymes such as pectinases, cellulases, and proteases. The pectin in the middle lamella of plant tissues is enzymatically degraded by protopectinase, pectin methylesterase, pectin lyase, and polygalacturonase to completely hydrolyze the galacturonan polymer to its constituent galacturonic acid. This improves the yield and clarification of various fruit juices. The acidic pectinases are used extensively in fruit juice manufacturing individually or synergistically with cellulases and proteases. Various microbial—fungal and bacterial—sources have been employed for production of pectinases using solid state as well as submerged fermentation. The purified or partially purified polygalacturonase and pectin methylesterase have been employed for clarification of various fruit juices in solutions or by using bioreactors. Pectinases are an important biochemical tool for fruit liquefaction, pressing, clarification, and production of clear concentrated fruit juices. This chapter contemplates the pectin structure, the hydrolyzing enzymes, their sources, production, and their application in the beverage industry.