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Purified apple pectins extracted under mild conditions were degraded by purified pectin lyase (EC 4.2.2.10) and pectate lyase (EC 4.2.2.2). The degraded pectins were fractionated by gel permeation chromatography and the degree of esterification and the sugar composition determined for each fraction. More than 90% of the uronic acid residues can be isolated as homogalacturonan chains. The neutral sugar residues can be detected in the column eluates as high molecular weight fragments. Models of the apple pectin molecules are presented. In the models the neutral sugars are present as side chains, arranged in blocks (in so-called ‘hairy regions’). The galacturonate residues in the hairy regions are esterified with methanol.