Analysis of potato glycoalkaloids by gas-liquid chromatography of alkaloid components

A gas-liquid chromatographic (GLC) method has been developed for the analysis of potato glycoalkaloids by direct determination of the alkaloid components isolated by hydrolysis with 1N ethanolic HCl. Recoveries of solanidine from potato tubers and foliage fortified with solanine over a range approximately 0.5 to 5 times the glycoalkaloid originally present averaged greater than 95%, and the lower limit of sensitivity was 0.25 mg/100 g using a nitrogen--phosphorus detector. A means of distinguishing solanidine and demissidine by formation of their respective 3 beta-trifluoroacetates with trifluoroacetic anhydride (TFAA) is demonstrated.