DISEASE GERMS IN MILK IOQ 



results from eating poisonous cheese. 1 Cases of poisoning from 

 eating ice cream are still more common. In all these instances 

 certain kinds of bacteria have developed in the food until they 

 have produced a considerable quantity of toxin, sufficient to 

 bring about violent illness to the person swallowing it. The 

 poison that causes the trouble has been separated from cheese 

 and called tyrotoxicon by Vaughan, and he has also found in 

 some samples of ice cream the species of bacterium that pro- 

 duces the toxin. 



The only way of protecting milk from this trouble is to use 

 it fresh, for it will never appear until the bacteria become 

 very abundant. No means can be given for avoiding poisoning 

 in cheese except that of using only good milk. We know so 

 little as to the matter that we are as yet helpless in regard to 

 it. Probably the use of lactic acid starters in cheese-making, 

 which is becoming common, will do much toward eliminating 

 such troubles which, fortunately, are very rare. 



Ice Cream Poisoning. Instances of this nature are more com- 

 mon and are probably more easily avoided. They occur almost 

 always in hot summer weather and are apparently most liable 

 to occur in the hot days that follow a period of cool weather. 

 That they are attributable to certain poisons in the ice cream 

 produced by the growth of bacteria is beyond question. It has 

 been shown above that if the milk is kept cool for a number 

 of days the lactic acid bacteria fail to grow; but at these low 

 temperatures other kinds of bacteria do grow, even though 

 somewhat slowly. If the cream collected from day to day is 

 kept for a number of days in the cool temperature of an ice 

 chest, there will be a continuous growth of these other types 

 of germs which are not checked by the development of the 

 lactic bacteria. During a period of cool days there is no de- 

 mand for ice cream; the cream accumulates in the ice chest, 



1 Vaughan. Med. and Sur. Reporter, Ixiii., p. 584, 1890. 

 Vaughan. Med. News, II., p. 644, 1887. 



