Koumiss, which is simply fermented milk, can easily be made at home after the receipt given below, and can then be had sweet and is much more palatable than the acid koumiss sold at pharmacies. It is a valuable drink or diet for invalids with weak digestion, or for dyspeptics.
For making koumiss it is necessary to have strong bottles (champagne bottles are best), and they must be scrupulously clean. A corking machine is requisite for driving in the corks. This is placed over the bottle; the cork, which has steamed an hour or more in hot water until softened, is placed in the side opening and the rammer pounded until the cork is free from the machine. The cork must be tied down to insure safety. A loop of twine is placed over it, then drawn tight around the neck of the bottle, brought back, and tied over the top of the cork.
A champagne tap for drawing the koumiss is also necessary, as it contains so much gas, it is impossible to draw the cork without losing a good part of the contents of the bottle.
Fill quart bottles three quarters full of fresh milk; add to each one a tablespoonful of fresh brewer's yeast and a tablespoonful of sugar syrup. The syrup is made by boiling sugar and water together to a syrup (the sugar must be used in this form). Shake the bottles for some minutes to thoroughly mix the ingredients, then fill them nearly full with milk and shake them again. Cork and tie them, and stand them upright in a cool place for two and a half days; then turn them on the side and use as needed. They should be kept in a cool, dark place, so the fermentation will be slow, and the temperature should be about 52 deg., or low enough to prevent the milk from souring.
Brewer's yeast is best and gives the koumiss the taste of beer; but compressed yeast may be used, a fifth of a cake dissolved being added to each bottleful of milk.