Comparação entre centrifugação e microfiltração na clarificação do suco tropical de maracujá

Abstract

Aiming at n alternative to the conventional centrifuge process of clarification, this work presents a study of the microfiltration processes to clarify the tropical juice of passion fruit. The influence of transmembrane pressure and the enzyme pre-treatment of the juice were studied in the process of clarification by microfiltration. Tests of microfiltration for clarification of tropical juice of passion fruit were performed in a microfiltration unit built in stainless steel. The ceramic membranes used have diameter cut-off 0.3 and 0.8 μm. The levels of transmembrane pressure investigated were 1.0 and 3.0 bar in an isothermal process at 35°C. The concentrations of Cytrozym Ultra L enzymes used in the pre-treatment of the juice were 100 and 200 ppm. The condition that resulted into a better quality of micro filtered juice was with membrane of 0.3 μm at 1.0 bar operated with juice pre-treated with 100 ppm of enzyme. In this condition, a permeate flow equal to 56 kg h-1 m -2 was obtained and resulting in 100% reduction of solid matter and 97% reduction in turbidity. The process of centrifugation with the same juice showed equivalent results, but the reduction of suspended solids was lower than the observed for microfiltration. The microfiltration allowed obtaining a juice free of suspended particles, which was the objective of this work.