EFFECT OF GLUCOMANAN COATING ON RIPENING AND QUALITY OF PAPAYA CULTIVAR 'RED MARADOL'

Abstract

Glucomanan prepared from konjac (Amorphophallus sp.) has been widely used in the food industry as an emulsifier. Moreover, it can also form a gel and edible film. Because of these properties, konjac glucomanan (KGM) might have potential applications in postharvest research. In this study, 0.1% KGM was applied on the surface of papaya cv. Red Maradol to delay ripening and maintain the quality. There was no significant difference in peel colour change of papaya in both treatments during storage at 13°C. In contrast, pulp colour change of KGM-coated papaya was significantly delayed as indicated by lower a * and b* values, and higher hue angle value compared with the control. Weight loss of papaya in both treatments increased during storage and there was no significant difference between treatments. Firmness of papaya in both treatments decreased sharply although 0.1% KGM-coated fruit had higher firmness values than the control. Soluble solids content of control fruit was higher than in 0.1 % KGM-coated fruit indicating that KGM coating could retard the ripening of papaya. Coating with 0.1 % KGM modified the atmosphere inside the fruit where O 2 was lower and CO 2 higher compared with the control.