Encapsulation of Watermelon Rind Extract in Chitosan Microcapsules: Analysis of Physical Properties and Flavonoid Release Ability

Abstract

Along with the increase in watermelon production, the amount of watermelon rind waste increased. The total mass of fruit rind in a watermelon reaches around 30 percent and this fruit rind can increase the quantity of organic waste in Indonesia. The outer portion of the watermelon rind has a green layer containing a large amount of anthocyanin and a white layer containing flavonoids. In this study, the extract of watermelon rind containing anthocyanins and flavonoids was protected from damaging conditions using the ionic gelation encapsulation method. Chitosan (CN) was used as a natural polymer in this encapsulation method and sodium tripolyphosphate (TPP) was used as an ionic crosslinking agent. The total of flavonols content (TF), microstructure test, in vitro releasing test, and shelf life of microcapsules were observed in the various ratio between watermelon rind and the solvent. From the process, can be concluded that higher watermelon skin levels will produce the most flavonoid microcapsules (70g/35 mL). At 70g/35 mL or 2:1 g/mL watermelon skin levels give the best flavonoid release test results, especially if it will be applied to the pharmaceutical industry, which follows a controlled release method.