CHAPTER XXVIII. 



FERMENTED MILKS. 



DURING the past few years there has been a great in- 

 crease in the consumption of buttermilk and other fer- 

 mented milks. Buttermilk tablets and numerous other milk 

 preparations have appeared on the market, for most of 

 which a certain medicinal as well as food value is claimed. 

 These are sold under various, names, such as Zoulak, 

 Vitallac, Yoghurt, Matzoon, Bacillae, Kefir, Kumiss, 

 Lacto-Bacilline, etc. 



In practically all these fermented milks, lactic-acid fermen- 

 tation is the main one. This may or may not be accompa- 

 nied by a fermentation causing alcohol and carbon dioxide to 

 be formed. This latter is brought about chiefly by yeast 

 ferments acting on the milk sugar and other added sugars. 



Food Value. Since these products are all made of 

 milk, either whole or skimmed, the composition of which 

 is but slightly changed by the fermentation it undergoes, 

 it is evident that the food value of these fermented products 

 is practically the same as that of fresh milk. There is 

 possibly an increased digestibility of the casein, due to 

 the fact that it has been precipitated and is in a very 

 finely divided condition. Those products containing alco- 

 hol and carbon dioxide are said to have a stimulating action 

 upon the digestive organs. 



Principles Involved. In Metchnikoff's book " The 

 Prolongation of Life " there is a chapter on " Lactic 

 acid inhibiting intestinal putrefactions." He states that 

 the use of fermented milks in combating autointoxi- 



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