Koumiss is prepared by dissolving four ounces of white sugar in one gallon of skimmed milk, and placing in bottles of the capacity of one quart; add two ounces of baker’s yeast or a cake of compressed yeast to each bottle. Cork and tie securely, set in a warm place until fermentation is well under way, and lay the bottles on their sides in a cool cellar. In three days, fermentation will have progressed sufficiently to permit the koumiss to be in good condition.
The Whitehouse Cookbook, by Mrs. F.L. Gillette (Year 1887)