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The dextrins in beer exhibit a characteristic wavy distribution with respect to their molecular weight, so that these dextrins seem to fall into distinct groups. These groups of dextrins (I, II, III and IV corresponding to DP 5-10, DP 11-16, DP 17-21 and DP 22-27) have been isolated by gel-chromatography on Bio-Gel P-2.Debranching of the megalosaccharides in Groups II, III andIV by means of pullulanase shows that they contain two, three and four oc-1,6linkages respectively. The dextrins in Group I are either linear or singly- as multiply-branched megalosaccharides of DP 11-30. With respect to the fine structure of amylopectin, the implication is that although the average interior chain length is about 6 glucose units, at least 35% of the a-1,6 linkages occur in densely branched clusters (pairs, triplets, quadruplets, etc.), the interior chain length of which is about 3 glucose units. This in turn offers an explanation of the wavy distribution of the dextrins in wort and beer.

Dextrins from a sweet wort, prepared by infusion mashing, were fractionated by paper chromatography according to their molecular weights and further into linear and branched dextrins. Each fraction was treated with j9-amylase and with the debranching enzyme, pullulanase. The products of this enzymic hydrolysis were identified by paper chromatography. From the pattern of oligosaccharides so obtained, structures have been postulated for the dextrins with a degree of polymer ization of 4 to 8 glucose units. The linear dextrins, maltotetraose, maltopentaose, maltohexaose, maltoheptaose, and malto-octaose, were shown to be present in wort. In addition, at least eleven branched dextrins were found: 6a-ec-maltosylmaltose, 6-a-glucosyl-maltotriose, two branched pentasaccharides, two branched hexasaccharides, two branched heptasaccharides and three branched octasaccharides. T the detailed structures (i.e., the structures of Introduction^moiecular-weight-isomers) of the indi-

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