Determination of total vitamin C in fruit juices and related products by liquid chromatography: interlaboratory study.

摘要: A interlaboratory study was conducted to evaluate a liquid chromatographic (LC) procedure for the determination of total vitamin C in foods at levels 5-60 mg/100 g. Emphasis placed on fruit juices, although selected were also included study. Following dissolution sample water, endogenous dehydroascorbic acid converted ascorbic by precolumn reduction with dithiothreitol neutral pH. Total ascorbate determined C18 reversed-phase LC phosphate eluent pH 2.5, incorporating maintain reduced form, and UV detection 254 nm. Seven types juices tested 19 collaborators 7 countries. Three duplicate met criteria Youden pairs yielded repeatability relative standard deviation 5.80-14.66%. Reproducibility ranged from 6.36 35.54% (n = 10) HORRAT values 0.82-4.04. The method is suitable routine use products containing > 5 g recommended further validation AOAC INTERNATIONAL International Fruit Juice Union.