title: Physicochemical properties of modified citrus pectins extracted from orange pomace.
abstract: Modified pectin is a polysaccharide rich in galacturonic acid altered by pH adjustment and thermal treatment used especially as an anti-cancer agent. The aim of this work was to study the physical and chemical properties of modified pectins extracted from orange pomace with citric and nitric acids. The galacturonic acid content, degree of esterification, Fourier Transform Infrared Spectroscopy profile, molecular weight, intrinsic viscosity, rheological properties and antioxidant activity of the pectins were evaluated. The modification process caused the de-esterification of pectins and a decrease of molecular weight due to removal of neutral sugars, maintaining the linear chain of galacturonic acid. Such changes also caused a significant increase in the in vitro antioxidant activity (p ≤ 0.05) and influenced the rheological properties of pectin, reducing its viscosity. This work showed that the modification of pectin from orange pomace with citric and nitric acids altered its structural and physical characteristics as well as its biological activity toward a free-radical.
authors.affiliation: Programa de Pós-Graduação em Tecnologia de Alimentos (PPGTA), Universidade Tecnológica Federal do Paraná, Campus Campo Mourão, Brazil.
authors.forename: Simoni Spohr
authors.initials: SS
authors.lastname: Venzon
authors.affiliation: Coordenação de Alimentos (COEAL), Universidade Tecnológica Federal do Paraná, Campus Ponta Grossa, Brazil.
authors.forename: Maria Helene Giovanetti
authors.initials: MH
authors.lastname: Canteri
authors.affiliation: Programa de Pós-Graduação em Ciência e Tecnologia de Alimentos, Universidade Estadual de Ponta Grossa, Ponta Grossa, Paraná Brazil.
authors.forename: Daniel
authors.initials: D
authors.lastname: Granato
authors.affiliation: Departamento Acadêmico de Alimentos (DALIM), Universidade Tecnológica Federal do Paraná, Campus Campo Mourão, Brazil.
authors.forename: Bogdan Demczuk
authors.initials: BD
authors.lastname: Junior
authors.affiliation: Departamento Acadêmico de Química e Biologia (DAQBi), Universidade Tecnológica Federal do Paraná, Campus Campo Mourão, Brazil.
authors.forename: Giselle Maria
authors.initials: GM
authors.lastname: Maciel
authors.affiliation: Programa de Pós-Graduação em Tecnologia de Alimentos (PPGTA), Universidade Tecnológica Federal do Paraná, Campus Campo Mourão, Brazil.
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Stafussa
authors.affiliation: Programa de Pós-Graduação em Tecnologia de Alimentos (PPGTA), Universidade Tecnológica Federal do Paraná, Campus Campo Mourão, Brazil.
authors.forename: Charles Windson Isidoro
authors.initials: CW
authors.lastname: Haminiuk
keywords: Antioxidant activity; Degree of esterification; Fourier transform infrared spectroscopy; Modified pectin; Pectin; Rheological properties