pH-DEPENDENT YIELD AND PHYSICOCHEMICAL PROPERTIES OF PECTIN ISOLATED FROM CITRUS MAXIMA

Citrus maxima white pith was utilized for the isolation of pectin under acidified condition using L-(+)-tartaric acid, at extraction pH in the range of 1.0 and 2.0. The extraction yield and physicochemical properties (ash content, equivalent weight, methoxy content, anhydrouronic acid, degree of esterification) of the isolated pectin was investigated. The highest yield (70.2%) obtained in this extraction was at pH 1.0, 60 degrees C, 120 minutes. The optimized condition of the isolated pectin in this study was based on the yield and physicochemical properties, where pectin extracted at pH 2.0 and 60-80 degrees C for 60-120 minutes resulted in a 59.6% yield, with low ash content (2.82%), highest equivalent weight (1098.8) for gelling effect and highest DE (39.2%). The findings are within the range for a good quality pectin. The FTIR spectra of the isolated pectin at different pH mediums, but at constant temperature of 70 degrees C and extraction time of 60 minutes were compared. The presence of methyl esterified carboxyl (1696 cm(-1)) and carboxylate group confirms the presence of pectin. This isolated pectin as an innovative raw material is potentially applicable for adsorbents, thin films, environmentally-friendly agents and green corrosion inhibitors.