title: Environmentally friendly preparation of pectins from agricultural byproducts and their structural/rheological characterization.
abstract: Apple pomace which is the main waste of fruit juice industry was utilized to extract pectins in an environmentally friendly way, which was then compared with chemically-extracted pectins. The water-based extraction with combined physical and enzymatic treatments produced pectins with 693.2 mg g(-1) galacturonic acid and 4.6% yield, which were less than those of chemically-extracted pectins. Chemically-extracted pectins exhibited lower degree of esterification (58%) than the pectin samples obtained by physical/enzymatic treatments (69%), which were also confirmed by FT-IR analysis. When subjected to steady-shear rheological conditions, both pectin solutions were shown to have shear-thinning properties. However, decreased viscosity was observed in the pectins extracted by combined physical/enzymatic methods which could be mainly attributed to the presence of more methyl esters, thus limiting polymer chain interactions. Moreover, the pectins which were extracted by combined physical/enzymatic treatments, showed less elastic properties under high shear rate conditions, compared to the chemically-extracted pectins.
authors.affiliation: Department of Food Science and Technology, Carbohydrate Bioproduct Research Center, Sejong University, 98 Gunja-dong, Gwangjin-gu, Seoul 143-747, Republic of Korea.
authors.forename: Bockki
authors.initials: B
authors.lastname: Min
authors.forename: Jongbin
authors.initials: J
authors.lastname: Lim
authors.forename: Sanghoon
authors.initials: S
authors.lastname: Ko
authors.forename: Kwang-Geun
authors.initials: KG
authors.lastname: Lee
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Lee
authors.forename: Suyong
authors.initials: S
authors.lastname: Lee
mesh_terms: D000383:Agriculture; D002241:Carbohydrates; D003247:Conservation of Natural Resources; D004548:Elasticity; D052918:Environmental Restoration and Remediation; D004952:Esters / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry*; D027845:Malus; D008970:Molecular Weight; D010368:Pectins / Q000737:chemistry*; D012212:Rheology; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods; D014783:Viscosity
chemical_list: D002241:Carbohydrates; D004952:Esters; D006603:Hexuronic Acids; C007819:galacturonic acid; D010368:Pectins