ESSAY XXL 



OBSERVATIONS ON A METHOD OF PRESERVING 

 VINEGAR. 1782. 



IT is a fact generally known that vinegar, of whatever 

 kind, will not keep long ; but, in the course of a few weeks, 

 especially in the warm temperature of summer, grows turbid, 

 and that its surface is covered with a thick mucilaginous 

 substance ; during which period the acid disappears by 

 degrees, and at last is entirely lost ; whence the vinegar 

 must very often be thrown away. Now, in order to avoid 

 this corruption of the vinegar, four methods have been 

 discovered. The first is, to prepare the vinegar very strong 

 and sour at first. . It is well known that such vinegar keeps 

 for several years ; but as there are few people who prepare 

 their own vinegar, and as most content themselves with 

 buying it as it is to be had in the shops, there are of course 

 but few who can make use of this method. The second 

 method is to concentrate the vinegar by congelation ; after 

 which a hole is made in the crust of ice which covers it, 

 through which the part that is not congealed is let out 

 and afterwards put into bottles. This manipulation answers 

 well enough ; but as nearly one-half is lost, because that 

 which forms the crust of ice is, for the most part, nothing 

 but water, good economists dislike it. The third method is 

 to prevent the access of air, viz. to fill the bottles full, and 

 keep them perfectly well corked. Though vinegar by this 



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