VINEGAR- MA KING. 221 



process is also dependent upon the presence and active growth of the 

 vinegar plants. 



Use of Pure Cultures in Vinegar-making. The different 

 types of vinegar-making organisms vary much, requiring quite 

 different conditions of temperature for their best work. In the 

 processes of manufacture hitherto used considerable losses have 

 resulted from the fact that the acetic acid formed is destroyed by 

 the further action of the bacteria. The fermentation is apt to be 

 irregular and, even under the same conditions, does not always 

 produce equally desirable results. The reasons for the irregularities 

 are to be found in the fact that, in different factories, sometimes 

 even in the same factory at different times, many varieties of the 

 vinegar organisms are found. Moreover, several of these organisms 

 are almost sure to be found together in any mass of natural " mother." 

 It is impossible to devise conditions that will be most favorable for 

 all of the organisms, and hence, with a "mother" composed of 

 many varieties, there is sure to be some loss. Theoretically, it 

 would seem that vinegar-making could be improved by the use 

 of pure cultures of these organisms. With a pure culture it would 

 be possible to make the conditions such as to produce the best 

 results with the variety in question, and thus prevent the losses 

 that come from one variety destroying the product of another 

 variety. The use of pure cultures has revolutionized brewing, 

 has greatly improved the methods of butter-making, and is rapidly 

 changing the process of cheese-making. Bacteriologists feel 

 confident that the same principal can be applied to vinegar-making. 



Hitherto there has been but little application of pure cultures 

 to vinegar-making. To obtain absolutely pure cultures is difficult, 

 and to keep them pure from subsequent contamination is more 

 difficult still. Vinegar-makers have not thought the advantages 

 derived from such methods sufficient to pay for the labor and trouble 

 of applying them. They have, to a considerable extent, adopted 

 rougher methods of obtaining the vinegar organism in quantity 

 and in a comparatively pure condition. A little white spirit vinegar 

 is filtered through fine bolting cloth to remove the vinegar eels. 

 This is mixed with a little alcohol of 90 per cent, volume, and some 



