Production of highly valued vegetable juice by osmotic distillation technique: Optimization of process parameters

Osmotic distillation (OD) was investigated for the concentration of vegetable juice, in sync with the increasing consumer interest towards natural and healthy foods. Celery juice first underwent a filtration step for removal of suspended solids, then a concentration step by OD. An OD plant was set up with a hollow fibre membrane module, where a concentrated solution of CaCl2 (60% w/v) was used as extraction brine circulating in counter current with the celery juice. Preliminary tests were performed to identify the optimal process parameters (i.e., flow rate, volumes, etc.). Celery juice was concentrated from 3.7 to 22.4 °Brix after 200 min of processing. The content of beneficial compounds and antioxidant activity were preserved after the OD process obtaining a concentration of the solution without loss of phenolic compounds.