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Starch is measured as glucose (g/100g). Starch values are computed as glucose multiplied by a hydration factor of 0.9, because the total weight of glucose released is higher than the weight of the starch. The reason for this is that one molecule of water is required for every covalent bond hydrolyzed, which adds to the hydrolysis products that becomes glucose.

To determine available carbohydrates by direct analysis of individual carbohydrates, also the amount of starch needs to be determined.

Most analytical procedures for the measurements of starch involve enzymatic hydrolysis of starch and subsequent measurement of the product of analysis, which is glucose. For this hydrolysis enzymes are used that are derived from enzymes present in the intestinal system: amyloglucosidase, pullulanase and mixtures of pancreas extracts containing alpha-amylase. However, sometimes acid hydrolysis is used.

Because intact starch granules are resistant for (enzymatic) hydrolysis it is essential to solubilise the starch e.g. by heating it with water prior to the hydrolysis step.