THE JOURNAL OF KMUTNB

Volume 32, No. 02, Month APRIL, Year 2022, Pages 478 - 485

Properties of pectin from watermelon rind extracted by conventional and microwave heating methods

Sirima Chinnasarn, Kusuma Mongsa

Abstract Download PDF

Properties of pectin from watermelon rind extracted by conventional and microwave heating methods were examined by using 2 acid extractants, 0.05 M hydrochloric acid and nitric acid. The ratio of dry watermelon rind powder to acid was 1 : 12 (w/v). The conventional heating method was heating at 95°C for 60 minutes in a shaking water bath. The microwave heating method was heating in a microwave oven with an output power of 800 W for 3 minutes. Results revealed that the equivalent weight, degree of esterification, water holding capacity and solubility of pectin extracted with hydrochloric acid were higher than those of pectin extracted with nitric acid. The microwave heating method increased the equivalent weight and degree of esterification of pectin. Watermelon rind pectin could be classified as high methoxyl pectin. The pectin obtained from hydrochloric acid extraction combined with microwave heating could provide stability to pineapple jam similar to that of commercial pectin.

Keywords

Watermelon Rind; Pectin; Microwave; Extraction

---