Clarification of passion fruit juice with chitosan: Effects of coagulation process variables and comparison with centrifugation and enzymatic treatments

摘要

Clarification is an important step in the fruit juice processing industry. In this study, chitosan from shrimp shells is proposed as an alternative aid for passion fruit juice clarification being a natural and environmental friendly adsorbent. Experiments were carried out in Jar tests varying chitosan concentration, pH, and slow velocity speed and time. The obtained results were evaluated in terms of turbidity, color, total soluble solids (TSSs), and viscosity reductions. The best condition found in these tests for chitosan treatment was compared with centrifugation and enzymatic treatments. Two different rotation speeds (4000 and 12,000 rpm) were applied for the centrifugation process. Enzymatic treatment was carried out with 1 mL L~(-1) of Pectinex 3X L (Novo Nordisk, Switzerland) for 90 min, at 50℃. The enzymatic treatment was reliable only for viscosity reduction, while the chitosan treatment after a mild centrifugation showed the best result for passion fruit clarification.