Routine method for quantification of starch by planar chromatography (HPTLC)

Starch is widely distributed in diverse plant organs as a reserve carbohydrate; it is also a major source of carbohydrates in human food. Because of its importance, different methods have been developed to measure the starch content of food and feed. Planar chromatography has been used to measure starch content of cereal products. The starch was hydrolyzed using alpha-amylase and amy-loglucosidase and the resulting glucose was separated on silica gel 60 HPTLC plates and quantified at lambda = 520 nm after derivatization. The glucose calibration plot was linear between 100 and 300 ng per spot with a coefficient of determination (r(2)) of 0.9959. The limits of detection (LOD) and quantification (LOQ) for starch as glucose were 0.26 and 0.51 (g per 100 g), respectively. The mean concentrations of starch in wheat flour and in starch premix (an industrial product) were 74.56 +/- 2.58% and 84.85 +/- 1.96%, respectively. The proposed method was shown to be a precise, selective, and sensitive means of measuring starch in cereal products.