STABLE, CONVENIENT-WORKING EXTRACTANTS FOR THE DETERMINATION OF L-ASCORBIC-ACID IN CITRUS EXTRACTS

As an effort to find a more stable, convenient-working extractant than regularly used methaphosphoric acid for determination of L-ascorbic a cid (AA) in citrus extracts, several extractants for assay of AA were examined. The extractants tested were (I) 15 g stick HPO3 + 40 ml acet ate + 450 ml H2O, (II) 0.5% stick HPO3 + 0.2% Oxalate + H2O, (III) 0.2 % Oxalate + 5% Acetate + H2O, (IV) 0.2% Oxalate + 10% Acetate + H2O, ( V) 7% Citrate + 0.5% Malate + H2O. Based on measurements of AA stored in the extractants and AA content in the juice of Citrus limon Burm. c v. Frost Nucellar Lisbon, the combinations of oxalate plus acetate res ulted in more convenient, less expensive and more stable extractants.