This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
This is a beverage which has been used by the nomadic tribes of Asia for centuries. It is made by the Tartars of mares' milk, and now is made of pure cows' milk, with the addition of a little sugar, thus making it chemically equal to mares' milk.
Formula I. (Wilkens). - A clean champagne bottle is filled with the fresh milk, twenty or thirty grammes of sugar are added, and then compressed yeast about the size of two peas; the bottle is well corked, the cork tightly secured, and the milk kept in a warm room for two days, and frequently shaken during that time; afterward the bottle is placed in an upright position in the cellar, and after three more days the koumiss is fit for use.
Formula II. (Wolff).- Grape sugar (glucose), one-half ounce; water, four ounces; compressed yeast, twenty grains; cows' milk sufficient for a quart champagne bottle; ferment for three or four days at 10° C. (50° F.) or less; this koumiss will keep four or five days.