18 BULLETIN 319, TJ. S. DEPARTMENT OF AGRICULTURE. 
(4) Add the yeast culture to the buttermilk in the proportion of 
one teaspoonful to a quart of buttermilk. 
(5) Mix thoroughly and bottle. The bottles should be very strong, 
as sufficient gas pressure is sometimes generated to break ordinary 
bottles; the heavy bottles used for ginger ale or other carbonated 
drinks answer this purpose very well. They should be carefully 
cleaned and boiled or steamed before filling ; fill them full and stop- 
per tightly, wiring or tying the stoppers securely in place. 
(6) Place in a cool place to ferment. 
If the fermentation is too active the kefir will have a yeasty taste 
and the curd is likely to become lumpy and filled with large gas bub- 
bles. A temperature of 18° C. (65° F.) to 21° C. (70° F.) will be 
found satisfactory for kefir which is to be used on the third or fourth 
day. The floor of a cool cellar is a convenient place to ferment kefir 
made in the home. The bottles should be shaken as often as may be 
necessary to keep the curd in a finely divided condition. The finished 
product should be smooth and creamy, effervesce rapidly when 
poured from the bottle, and have the pleasant, acid taste of but- 
termilk, with the added sharpness caused by the gas and the trace 
of alcohol. Kefir 2 or 3 days old may have a yeasty taste, but if it 
has been properly made this will disappear as the fermentation of 
the sugar nears completion; made under these conditions it should 
be used when 3 to 5 days old, but if put on ice it may be held for a 
week or even longer. 
KUMISS. 
The missionary monks and other wanderers who first penetrated the 
undulating, treeless plains of European Russia and central and south- 
western Asia brought back descriptions of a fermented drink which 
in the light of more recent investigations is easily recognized as 
kumiss. These vast prairies are inhabited by tribes of nomads who 
live in tents or squalid huts in the winter and wander during the 
summer, seeking pasture for their horses, their herds of cattle, or 
flocks of sheep. They are all horsemen, and by a process of selection 
in which they have probably played only a passive part have de- 
veloped an exceptionally hard} 7 race of horses. The mares give much 
more than the ordinary amount of milk, which constitutes almost the 
entire food of the people during the summer. This is never used in 
the fresh condition, but is fermented to make kumiss. Unlike kefir, 
there is no dried " ferment," ;i seeds," or ' ; grains " with which the 
fermentation of the mare's milk is started. It is the practice of the 
natives, when it becomes necessary to establish the fermentation anew. 
to add to milk some fermenting or decaying matter, such as a piece of 
flesh, tendon, or vegetable matter. Whatever the material used to 
supply the essential organisms, it is evident that the milk is so cared 
