EXPERIMENTAL AND DFT STUDY OF GELLING FACTOR OF PECTIN
Keywords:
Pectin, coffee pulp, density functional theoryAbstract
Industrial processing of coffee cherries is done to isolate coffee powder by removing shell and mucilagenous parts from coffee pulp. The process produces coffee with less quantity of caffeine, tannins, polyphenols, and pectin. Pectin is a methylated ester of polygalacturonic acid which divides into two groups based on degrees of esterification. In this work, the gelling behavior of pectin was studied. It was found that value of galacturonic acid was 447.24 mg and an equivalent weight was 207.47. In addition, Density Functional Theory (DFT) was applied to study the chemical structure of extracted pectin with pectin molecular variation of 2-8 monomers, using different amounts of methoxyl substitution. It was found that molecular weight could affect to the molecular structure as the longer the molecular structure, the more linearity it presents.
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