212 DOMESTIC ANIMALS, DAIRYING, ETC. 



sugars is possessed by many kinds of bacteria, but is so character- 

 istic of a certain group that they^ are commonly spoken of as the 

 lactic-acid bacteria. These bacteria have been described as distinct 

 species or varieties under many names. Among these may be men- 

 tioned Bacterium guntheri, Bacillus acidi lactici, Streptococcus lac- 

 ticus, and many others. In spite of the confusion in nomenclature 

 it is evident that the term "lactic-acid bacteria" includes a fairly 

 well-defined group of closely related varieties possessing in common 

 several definite characters. Variations from the type in minor char- 

 acters produce an almost infinite number of varieties. These varia- 

 tions may be in the ability to ferment different sugars, in the ten- 

 dency to grow in chains, in the kind of flavor formed in milk, in 

 the intensity of acid formation, and in the ability to produce patho- 

 logical conditions in animals. 



In making buttermilk from milk the same procedure should be 

 followed as in making a starter for cream ripening. A good, clean- 

 flavored mother starter should be carried along with every possible 

 precaution to prevent contamination. Good commercial cultures 

 can be obtained, but if it is not convenient to use one of these a 

 natural starter can be secured. 



Milk to be used for making buttermilk should be fresh and 

 clean flavored. Good buttermilk can not be made from milk that 

 is tainted or too old to be used for other purposes. Skimmed, partly 

 skimmed, or whole milk, as desired, may be used. 



Butter makers in the Northwest make a very refreshing and 

 nutritious drink by adding sugar and lemons to buttermilk. As the 

 casein is already precipitated, the acid juice of the lemon has no 

 effect. Slightly more sugar and lemon juice are necessary than in 

 making ordinary lemonade, and the mixture should be well iced. 



Kefir. Fermented milks have evidently been extensively used 

 by the people of southern Russia, Turkey, the Balkan countries, 

 and their neighbors for many centuries. The natives have no 

 records and few traditions of the origin of the milks they use, and 

 it is probable that their preparation and use developed gradually 

 by accident and cumulative experience. One of the first of the fer- 

 mented milks known to Europeans was the kefir, made in the Cau- 

 casus Mountains and neighboring regions from the milk of sheep, 

 goats, and cows. Kefir differs from most of the fermented milks of 

 the Mediterranean countries in that it is made from a dried prepa- 

 ration and contains considerable quantities of alcohol and gas. 

 Kefir is made by many tribes under varying names, as hippe, kepi, 

 khapon, kephir, kiaphir, and kaphir, all of which are said to come 

 from a common root signifying a pleasant or agreeable taste. 



The mountaineers of the Caucasus depend for a large part of 

 their food on kefir, which they prepare in leather bottles made from 

 the skins of goats. In the summer the skins are hung out of doors 

 either in the sun or in the shade according to the weather, but in 

 winter they are kept in the house. The bags are usually hung near 

 a doorway, where they may be frequently shaken or kicked by each 

 passer-by. Fresh milk is added as the kefir is taken out, and the fer- 



