Abstract
Sodium bisulfite, cysteine, dithiothreitol, and sodium diethyldithiocarbamate (Na Dieca) inhibit enzymatic blackening in potatoes by initially inhibiting the oxidation of tyrosine by polyphenol oxidase. Sodium bisulfite and Na Dieca also cause enzyme inactivation. Although cysteine and dithiothreitol inhibit tyrosine oxidation for a period of time, they do not appear to inactivate the enzyme. Dithiothreitol is a much more effective inhibitor of tyrosine oxidation than cysteine.
Ascorbic and dihydroxyfumaric acids inhibit enzymatic blackening by reducing the dopaquinone to dopa. When the reducing agents are completely oxidized, blackening can occur.
Resumen
Bisulfito de Sodio, cisteína, ditiotreitol y dietil ditiocarbonato (Dieca de Sodio) inhiben el obscurecimiento (necrosis) enzimática en papas a causa de la inhibición en la oxidación de la tirosina causada por la oxidasa poliferiótica. El bisulfito de Sodio y el Dieca de Sodio también causan inactivación de la enzima. Aunque la cisteína y el ditiotreitol inhiben la oxidación de la tirosina por un cierto período, aparentemente no inactivan la enzima. El Ditiotreitol es un inhibidor much más efectivo de la oxidación de la tirosina que la cisteína.
Los ácidos ascórbico y dihidroxifumárico disminuyen el obscurecimiento enzimático a través de su acción de reducir la dopaquinona a dopa. Cuando los agentes reductores son oxidados totalmente se produce el obscurecimiento del tejido.
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Published with the approval of the Director of the Idaho Agricultural Experiment Station as Research Paper No. 8055.
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Muneta, P. Comparisons of Inhibitors of Tyrosine Oxidation in the enzymatic blackening of potatoes. American Potato Journal 58, 85–92 (1981). https://doi.org/10.1007/BF02854377
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DOI: https://doi.org/10.1007/BF02854377