Method for the direct determination of available carbohydrates in low-carbohydrate products using high-performance anion exchange chromatography.

摘要

An improved method for direct determination of available carbohydrates in low-carbohydrate products was developed and validated for a low-carbohydrate soy infant formula. The method involves modification of an existing direct method to improve specificity, accuracy, detection levels and run times through a more extensive enzymic digestion to capture all available (or potentially available) carbohydrates. The digestion process hydrolyses all common sugars, starch and starch derivatives down to their monosaccharide components, glucose, fructose, and galactose, which are then quantitated by high-performance anion-exchange chromatography with photodiode array detection. Method validation consisted of specificity testing and 10 days of analysing various spiked levels of mixed sugars, maltodextrin and corn starch. The overall RSD was 4.0% across all sample types, which contained within-day and day-to-day components of 3.6 and 3.4%, respectively. Overall average recovery was 99.4% (n = 10). Average recovery for individual spiked samples ranged from 94.1 to 106% (n = 10). It is expected that the method could be applied to a variety of low-carbohydrate foods and beverages.