Evaluation of the pH, titratable acidity and ascorbic acid content of juices commonly consumed by children

Abstract

Juices are beverages that are consumed by many individuals on a daily basis with children being one of the highest consumers. Juices are obtained by extracting the natural liquid out of fruits or vegetables. This in vitro study aims to evaluate the endogenous pH, titratable acidity and ascorbic acid content of juices commonly consumed by children. Fifteen (15) commonly consumed juices were evaluated. The pH of each juice was determined using a digital pH meter. The titratable acidity was assessed by titrating 0.1 N sodium hydroxide solution against 30 ml of each juice until the end point was reached. The ascorbic acid content of 10 of the juices was determined by iodometric titration. The pH of the evaluated samples ranged from 3.40 to 5.74, with 93% of the juice samples having pH values less than the critical pH (5.5). The titratable acidity of the juice samples also ranged from 5.43 g/100 ml to 2.14 g/100 ml. Of the juice samples, 33.33 % did not contain ascorbic acid but for the others, the ascorbic acid level ranged from 6.739 mg/100 ml to 1 mg/100 ml. All juices were acidic.

Keywords: Fruit juice, pH, titratable acidity, ascorbic acid content