Effect of anti-browning treatments on physicochemical characteristics and sensory acceptance of green roselle pickle (Hibiscus sabdariffa L. var. UKMR-3)

Abstract

The inhibition of enzymatic browning catalyzed by polyphenol oxidase (PPO) is still an important challenge in food processing as shown in the case of green roselle, where its utilization as raw materials of food products is hindered by its susceptibility to enzymatic browning. The aim of this work was to evaluate the effect of anti-browning treatments on physicochemical characteristics and ·sensory acceptance of green roselle pickle (Hibiscus sabdariffa L. var. UKMR-3). Two types of physical (hot water blanching and steam blanching) and three types of chemical treatments (0.15M citric acid, 0.15M ascorbic acid and 0.15M calcium chloride) were applied as anti-browning treatments. Different anti-browning treatments significantly affected (p<0.05) the physicochemical characteristics (total soluble solids, yellowness, pH, titratable acidity, firmness and proximate compositions) and sensory properties (color, texture and overall acceptance) of green roselle pickle. Green roselle pickle treated with 0.15M calcium chloride is the suggested treatment since it had the highest firmness and high greenness. It also had the second highest score of overall acceptance and second highest vitamin C content after IO days of pickling. These results showed that with proper anti-browning treatment, green roselle has potentials to be produced into food products such as pickle.