OPTIMIZATION OF PRE-TREATMENTS TOWARDS REHYDRATABLE TORCH GINGER (Etlingera elatior) FLOWER CHARACTERISTICS

Abstract

Torch ginger (Etlingera elatior) is an indigenous plant found in South-Asian region which is known for its attractive appearance, pink color, and health benefits. The torch ginger flower shows potential for its rehydratable form development to increase added value, convenience, and shelf life. Some of the most important characteristics in the rehydratable torch ginger flower development are moisture content, color difference, rehydration ratio, and antioxidant activity. Cabinet drier has been used widely in the development of dehydrated food due to its affordability, however shows problem in the degradation of quality. On the other hand, pre-treatments such as steam blanching and sodium metabisulphite soaking has been known to retard quality degradation during drying in dehydrated products. In this study, optimization was done using Response Surface Methodology (RSM) in Design Expert v11.0 software with 13 combination runs of steam blanching time (ranging from 30-180 seconds) and sodium metabisulphite soaking concentration (ranging from 0.15%-0.40%). The optimum pre-treatments in the experiment were found to be 180 seconds of steam blanching continued by soaking in 0.331% sodium metabisulphite solution which resulted in moisture content of 7.96%, rehydration ratio of 4.65, color difference of 12.56, and antioxidant activity of 39.36% with the desirability of 0.719.