Pectins in Processed Fruit and Vegetables: Part I - Stability and Catalytic Activity of Pectinases
Pectinases catalyze numerous pectin conversion reactions strongly impacting on the quality of fruits, vegetables, and the related intermediate and end products. The effect of processing on the stability and catalytic activity of pectinases is of prime importance to food processors since desirable and/or deleterious reactions can be tailored (accelerated or inhibited) meeting specific quality targets. Of the multiple endogenous enzymes involved in the modification and degradation of pectin, pectinmethylesterase (PME), and polygalacturonase (PG) have been widely investigated in the context of fruit and vegetable processing. This review covers the stability and catalytic activity of endogenous plant PME and PG including the quantitative approaches applied in inactivating and/or boosting the catalytic activity of the enzymes in purified and real food systems. This will be discussed in the context of both traditional and novel food processing technologies.