Immobilisation of pectinases into PVA gel for fruit juice application

In this study, for the first time, the use of polyvinyl alcohol gel in the form of LentiKats^® to immobilise pectinase was investigated and its application in fruit juice clarification was evaluated. Six pectolytic enzymes were tested for their polygalacturonase (PG) and pectin lyase (PL) activities. Panzyme YieldMASH and Panzyme Smash XXL exhibited maximum PG and PL activity, respectively (P < 0.05), in free and immobilised forms. The immobilised enzymes revealed a good adaptability to an acidic solution like fruit juice. Moreover, the immobilised Panzyme YieldMASH and Panzyme Smash XXL retained about 60% and 74% residual activity, respectively, in the second cycle and more than 30% during the third cycle. After that, both immobilised enzymes retained about 20% of their initial activity after repeating eight times without a significant decrease in the observed activity. The best result in terms of turbidity reduction was obtained in apple juice with immobilised Panzyme YieldMASH (about 80%), and the same % of turbidity reduction was successfully retained in the two following uses.