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.

The carbohydrate composition during fermentation of low calorie beer, or more correctly low carbohydrate beer, has been examined. The low content of carbohydrates in the final beer is achieved by adding amyloglucosidase to the wort at the beginning of the fermentation. Amyloglucosidase is an exoenzyme capable of degrading non-fermentable dextrins almost quantitatively to glucose, which is then fermented.A full scale production of a low calorie beer "Kalorius" has been followed. The fermentation took three weeks, and was followed by five weeks of storage. Separation and detection of the carbohydrates were done by high performance liquid chromatography using a commercial carbohydrate column and refractive index detection.The results show an increased glucose content of approximately 60% on the first day of fermentation. Furthermore, it is found that amyloglucosidase degrades maltose and mallotriose to glucose. This leads to formation of glucose in such quantities that the yeast probably only metabolizes this single carbohydrate during the whole fermentation.

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