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The optimization of pectin extraction from Kaffir lime (Citrus hystrix) peel by microwave-assisted aqueous extraction for environmentally friendly pectin was investigated in this study. The response surface methodology (RSM) was applied for the experiment with 3 factors, which affected pectin yield (%), i.e., extraction temperature (90-120 ºC), extraction time (10-20 min) and liquid-solid ratios (40 : 1 to 80 : 1 mL/g). The results demonstrated that pectin yield predicted under the optimum extraction condition (time; 13.34 min, temperature; 98.21 ºC and liquid-solid ratio; 71.85 mL/g) was obtained at 20.18 % (w/w), and was lower than the experimental value (20.66 % w/w). Moreover, pectin obtained from Kaffir lime peel can be classified as low methoxyl pectin (6.34 %). The FTIR spectrum of the obtained pectin was similar to that of the standard of pectin. Hence, Kaffir lime is a potential raw material for pectin production. Besides, the aqueous extraction by microwave-assisted aqueous extraction can be used for a green pectin production.
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