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Dextrine or Starch Gum

Heat 4 gallons water in a water-bath to between 77° and 86° Fahr.; stir in 1½ or 2 pounds finely ground malt; raise the temperature to 140°, add 10 pounds potato or other starch; mix all thoroughly, raise the heat to 158°, and keep it between that and 167° for 20 or 30 minutes. When the liquor becomes thin, instantly raise the heat to the boiling point, to prevent the formation of sugar.

Strain the liquor, and evaporate it to dryness, as the dextrine will not keep long in a liquid form. Another method is to boil solution of starch with a few drops of sulphuric acid, filter the solution, and add alcohol to throw down the dextrine.

Or: Mix 500 parts potato starch with 1500 parts of cold distilled water and 8 parts of pure oxalic acid; place this mixture in a suitable vessel on a water-bath, and heat until a small sample tested with iodine solution does not produce the reaction of starch. When this is found to be the case, immediately remove the vessel from the water-bath, and neutralize the liquid with pure carbonate of lime. After having been left standing for a couple of days the liquor is filtered, and the clear filtrate evaporated upon a water-bath until the mass has become quite a paste, which is removed by a spatula, and, having been made into a thin cake, is placed upo n paper and further dried in a warm place; 220 parts of pure dextrine are thus obtained. (See No. 2925.)