Degree of Esterification and Gelling Properties of Pectin Structure in Coffee Pulp

Abstract:

Pectin is a high value functional food ingredient widely used as a gelling agent and stabilizer. The chemical structure of pectin has been the subject of scientific investigations for decades. Coffee producers remove beans; the other source of pectin, from coffee cherries is thrown away. Our study showed that pectin extracted from coffee pulp has high degree of esterification and methoxyl content of 93.75% and 7.87 respectively, which indicated good gelation properties. Nevertheless, here we were interested in the primary structure of pectin which is a complex polysaccharides that contains 1, 4-linked a-D-galactosyluronic acid (GalpA) residue. A theoretical dimension, density functional theory (DFT) with Generalized Gradient Approximation (GGA)/ BLYP functions, was utilized to study methylester substitution in pectin model compounds. For further discussion, the use of a COSMO model in different solvent showed the significant results in the difference torsion angle and HOMO diagram.

• Periodical: Key Engineering Materials (Volumes 675-676)
• Pages: 11-14
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.675-676.11
• Online since: January 2016
• Authors: Waleepan Rakitikul*, Piyarat Nimmanpipug
• Keywords: Coffee Pulp, Density Functional Theory, Gelation Properties

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