The greater availability of free sites in the cation exchange resin during initial few samples caused higher reduction in the juice constituents. However, during subsequent samplings the number of free sites on the resin, for bonding with juice constituents became lesser, resulting in reduced removal of amino acids and other soluble solids. Further, there was only 7.7, 5.1 and 12.9% loss in the acidity, ascorbic acid and total sugar of orange juice respectively, when 121 ml of juice was passed through the column in one lot. Since, the efficiency of cation exchange resin (Dowex-50 W) was maximum upto 6th sample , beyond which it decreased drastically , it was concluded that 121 ml of orange juice when passed through a glass column (5 cm internal diameter) packed with cation exchange resin (Dowex-50 W) upto a height of 8 cm could remove about 98.4% of the amino acids with minimum losses in other juice constituents. The same column can be washed and regenerated again and again without any practical loss in efficiency if the CER (Figs. 1 and 2). These findings are in close conformity with the earlier findings (Sharma et al. 2004, 2006).