Concentration of pineapple juice by osmotic evaporation

The aim of this work was to evaluate the process of osmotic evaporation to concentrate pineapple juice. In order to study the effect of pulp content on the performance, clarified and single strength pineapple juices were successively concentrated up to 57 g 100 g(-1) total soluble solids (TSS). Trials were carried out with a laboratory unit using saturated calcium chloride brine as the extracting phase. Under the operating conditions, the difference in temperature between the juice and the brine had a large influence on the water evaporation rate. The highest flux was obtained at 35 degrees C in the juice compartment and 20 degrees C on the brine side. Flux ranged from 2 to 13 kg h(-1) m(-2). It significantly decreased when the TSS content of the juice increased. For the same operating conditions, higher flux values were obtained when processing the clarified juice, which indicated an effect of pulp content on performance. At no time were significant changes observed in the quality of the products obtained from raw juices and juices from concentrates. (c) 2008 Elsevier Ltd. All rights reserved.