title: Structural characterization of oligosaccharides and polysaccharides from apple juices produced by enzymatic pomace liquefaction.
abstract: Eight apple pomace liquefaction juices were produced to characterize soluble cell wall material released by the action of pectolytic and cellulolytic enzyme preparations. Very high colloid values from 9.7 to 19.6 g/L were recovered from the juices by ethanol precipitation. The crude polysaccharides consisted mainly of galacturonic acid (49-64 mol %), arabinose (14-23 mol %), galactose (6-15 mol %), and minor amounts of rhamnose, xylose, and glucose. Separation of the polysaccharides by anion-exchange chromatography yielded one neutral, one slightly acidic, and one acidic polymer accounting for 60% of total colloids. Preparative size exclusion chromatography of the acidic fractions resulted in four polymers of different molecular weights and different sugar compositions. Among them, high molecular weight arabinans and rhamnogalacturonans as well as oligomeric fractions consisting of only galacturonic acid could be found. Linkage studies were performed on neutral fractions from anion-exchange chromatography and size exclusion chromatography. They revealed highly branched arabinans, xyloglucans, and mainly type I arabinogalactans.
authors.affiliation: State Research Institute Geisenheim, Department of Wine Analysis and Beverage Research, P.O. Box 1154, D-65366 Geisenheim, Germany.
authors.forename: Katri
authors.initials: K
authors.lastname: Mehrländer
authors.forename: Helmut
authors.initials: H
authors.lastname: Dietrich
authors.forename: Sabine
authors.initials: S
authors.lastname: Sembries
authors.forename: Gerhard
authors.initials: G
authors.lastname: Dongowski
authors.forename: Frank
authors.initials: F
authors.lastname: Will
mesh_terms: D001628:Beverages; D002241:Carbohydrates / Q000032:analysis; D002480:Cellulase / Q000378:metabolism*; D002848:Chromatography, DEAE-Cellulose; D003102:Colloids; D005511:Food Handling; D005638:Fruit / Q000201:enzymology*; D008970:Molecular Weight; D009844:Oligosaccharides / Q000737:chemistry* / Q000378:metabolism; D011096:Polygalacturonase / Q000378:metabolism*; D011134:Polysaccharides / Q000737:chemistry* / Q000378:metabolism
chemical_list: D002241:Carbohydrates; D003102:Colloids; D009844:Oligosaccharides; D011134:Polysaccharides; D011096:Polygalacturonase; D002480:Cellulase