STRUCTURAL ANALYSIS OF WORT DEXTRINS BY MEANS OF β-AMYLASE AND THE DEBRANCHING ENZYME, PULLULANASE

Abstract

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 β-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 polymerization 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: 6²-α-maltosyl-maltose, 6-α-glucosyl-maltotriose, two branched pentasaccharides, two branched hexasaccharides, two branched heptasaccharides and three branched octasaccharides.