1972 Volume 19 Issue 11 Pages 526-530
In order to estimate the quality of citrus fruits an attempt was made to apply the conductometric method to the determination of free acid content in juices.
(1) An intimate correlation between the amount of free acid and the specific conductivity was obtained with the diluted citrus juices.
(2) The correlation coefficient of Citrus unshiu juices was the highest in the diluted sample containing about 0.5% of the juice (r=0.994). The coefficient of Citrus natsudaidai juices was a little lower than that of unshiu.
(3) The regression of free acid upon specific conductivity indicated the highest correlation coefficient in case of the same species and the same dilution. The regressions of Citrus unshiu juices were identical during the period of maturity of fruits.
(4) It was found to be able to determine the free acid content directly from the conductivity by the use of the relationship between the titration value and the specific conductivity of diluted citrus juices without the influence of sugar.
