Koumiss (spelled also koumys and kumyss) is milk artificially prepared by simultaneous lactic acid and alcoholic fermentation. It was originally made by the natives in the steppes of southeastern Russia and other eastern countries as a refreshing and slightly intoxicating beverage. Of late years the idea has been advanced that it has some beneficial or curative influence in chronic diseases, such as phthisis, chronic bronchitis, chronic gastro-intestinal catarrh, and other wasting diseases, and as a result the manufacture of koumiss has been extensively introduced into the United States, and at many pharmacies it can be obtained daily, freshly prepared, in pint or quart bottles. It is probable that a large share of the benefit claimed for the native "koumiss cure " is attributable, like most "cures," to the favourable climate in which the patients live, especially during the months of May, June, and July, where the air is dry, clear, and aromatic.

Very advanced cases, and those having active fever, may not be benefited by the "cure," but koumiss may be given them at home. Koumiss is of great service as an easily digested food for many cases of obstinate gastric irritation and severe vomiting. In the latter it may be often tolerated when no other nutriment is retained. Its uses are therefore various both for infants and adults, and there are often cases in which it agrees better than pancreatinised milk or milk prepared in any other way.

The Manufacture Of Koumiss

The manufacture of koumiss may be conducted by several different processes. In southeastern Russia, especially in south Samara, the milk of a certain breed of mares is used, which is particularly rich in milk sugar but poor in fat and casein, and the animals are fed upon grasses which contain this sugar-forming material in abundance (Karrick).

Mare's milk, as compared with cow's, contains much more sugar (6 per cent) and less casein and fat (less than 3 per cent) (Biel).

The mares are light-coloured animals, unbroken, and are guarded with greatest care, not being allowed dry food, such as oats and hay. Pastured among mountains containing salt beds, they have access to running water, in which they can bathe frequently. They have large udders and abundant milk secretion, which is milked from four to eight times daily. The best koumiss is made in the early summer by pouring fresh milk into smoked leather bottles or sabas, to which is added a little sour cow's milk or old dry koumiss ferment. The skins are kept at a temperature about equal to the body heat and are frequently shaken for thorough mixing, and fermentation is allowed to proceed for three or four days.

In the United States koumiss is manufactured from cow's milk by the addition of some artificial ferment. Such home-made koumiss may be prepared as follows:

Take 2 teaspoonfuls of wheat-flour dough, 2 tablespoonfuls of millet flour, 1 tablespoonful of honey, 1 tablespoonful of beer yeast. Mix into a thin paste with milk. Place in a warm place to ferment. When fermented, put into a linen bag and hang in a covered jar with sixteen pounds of fresh milk. Let stand for twenty-four hours, or until the milk becomes acid, at a temperature of 86° to 900 F. Skim, decant, agitate for an hour, bottle and cork tightly, protecting the corks with wire fastenings. Keep in a refrigerator. Absolute cleanliness must be insisted upon throughout all the various manipulations; otherwise different forms of fermentation will result (Stange).

Properties

Koumiss when shaken froths readily. It has, when fresh, a slightly sour odour, agreeable bitter taste, and acid reaction. The specific gravity is 1.018 to 1.029. During fermentation alcohol is developed from the milk sugar, which forms lactic acid and glucose, the latter making alcohol and carbonic acid. The alcohol may reach 2.5 per cent, but koumiss made from cow's milk may not contain above 1 per cent. Koumiss becomes stronger in both taste and smell after keeping for a day or two. It is highly sensitive to temperature changes, and easily putrefies.

There are two varieties of koumiss prepared which differ in degree of fermentation and in their exhilarating and intoxicating properties. The lighter form contains less alcohol than the heavier, in which fermentation has proceeded further.

The following analysis by Stange illustrates the changes in composition which koumiss undergoes by prolonged fermentation:

Table of the Percentage Composition of the Several Strengths of Koumiss

(Stange)

Mare's milk.

KOUMISS - DURATION OF FERMENTATION.

6 hours.

18 hours.

30 hours.

4 days.

Carbonic acid

..

3.8

6.0

7.0

11.0

Alcohol

..

18.5

19.5

30.0

30.0

Lactic acid

3.9

5.6

6.4

6.4

Milk sugar

51

18.8

16.3

Albumin

23

22.5

22.6

20.0

16.0

Fat

19

18.9

20.0

I9.0

I9.0

Salts

5

4.5

4.0

4.0

4.0

The casein, after being first precipitated, is converted into peptones and an acid albumin. It should be remembered that the composition of koumiss is always changing unless the fermentation be constantly held in check by extreme cold. Koumiss grows more and more acid and keeps but a short time when exposed to the air. If spoiled, it may produce severe symptoms of ptomaine poisoning.

Koumiss is prepared in tablet form under the name of koumysgen, each tablet, it is claimed, containing 30 per cent of soluble casein. The tablets keep indefinitely in air-tight bottles, and when dissolved in water form a cooling effervescing food, possessing similar properties with koumiss, and it is cheaper. It is doubtful, however, whether any preparation can be made to reproduce all the peculiarities and advantages of fresh koumiss, which is so variable and delicate a substance.