The electrodialysis (ED) process was investigated to reduce the acidity of four tropical fruit juices, passion fruit, castilla mulberry, najanrilla and araza. In this part of the study, the results of physico-chemical and sensory analyses of juices treated were collected and compared to fresh juices. Low differences (< 10%) were observed whatever the ED configurations (conventional or bipolar ED) and operating conditions used. At a final pH of 4, the titrable acidity and organic anion concentration decreased of about 70% and 50-60%, respectively, for all the juices. Inorganic anions were almost eliminated, between 70% and 95%, while the sugar and cation concentration remained unchanged, except for the sodium concentration in conventional ED. Slight changes of colour were observed, except for the mulberry juice, because of the presence of anthocyanidins which varied in colour vs. pH. The sensory characteristics of juices were preserved, but a decrease in the intensity of odour was detected. Different nectars with the same sugar-acid ratio were prepared by mixing fresh and deacidified juices. Except for passion fruit, the increase in the juice content of the nectars did not improve significantly their aromatic quality. (c) 2006 Elsevier Ltd. All rights reserved.