1078 



VINEGAR 



2088 



perforated lid, is filled with shavings of beechwood ; by percolating through which, the 

 solution is exposed, over a very considerable surface, to the oxidising influence of the 



air, which passes in a current upwards through 

 the apparatus. One inch above the bottom is 

 a syphon-shaped discharge pipe o, the upper 

 curvature of which stands one inch below the 

 air-holes in the side of the tub ; so that, when 

 the liquid in the bottom of the generator, 

 which has passed through the shavings, collects 

 up to this level, it runs off into any vessel 

 placed beneath to receive it. 



The analogy between acetification and ordi- 

 nary processes of decay, and even combustion, 

 is well seen in this process ; for, as the oxida- 

 tion proceeds, the temperature of the liquid 

 rises to J00 or even 104 Fahr. ; but if the 

 temperature generated by the process itself be 

 not sufficient, the temperature of the rooms in 

 which the tuns are placed should be artificially 

 raised. 



By this methed 150 gallons of vinegar can 

 be manufactured daily in ten tuns, which one 

 man can superintend ; and the vinegar, in 

 purity and clearness, resembles distilled vinegar. 



It is better to avoid using liquors containing much suspended mucilaginous matter, 

 which, collecting on the chips, quickly chokes up the apparatus, and not only impedes 

 the process, but contaminates the product. 



The chips and shavings may with advantage be replaced by charcoal in fragments, 

 which, by the oxygen it contains condensed in its pores, still further accelerates the 

 process. The charcoal would of course require re-igniting from time to time. 



Processes for the rapid formation of vinegar have likewise been adopted in this 

 country. So long ago as the year 1824, Mr. Ham obtained a patent for the following 

 method, which is still in operation at several works : 



The apparatus consists of a large vat, in the centre of which is placed a revolving 

 pump, having two or more shoots pierced with holes, so as to cause a constant shower 

 of wash fermented wort to descend. The lower part of the vat is charged with 

 wash, the upper part with birch-twigs, piled as high as possible, but without inter- 

 fering with the revolution of the shoots. Between the surface of th 04 wash and the 

 joist which supports the birch-twigs, a space of tliree or four inches is unoccupied, and 

 holes are perforated in it, to admit a current of air, either from the atmosphere or from 

 a blowing apparatus. 



If the wash be maintained at a temperature of from 90 to 100 Fahr., and the supply 

 of liquid duly proportioned to the mass of the twigs, a charge is generally acetified 

 in about a fortnight. The acetification can of course be arrested at any moment, and 

 the current of air increased or diminished at will. 



Generally in England much larger tuns are iised than in Germany, the larger mass 

 of matter thus undergoing oxidation generating so much heat that no artificial eleva- 

 tion of temperature is required ; and in consequence of the promotion of the process in 

 this way, one of these largo tuns, fifteen feet wide at the bottom, fourteen at the top, 

 and thirteen high, turns out as much vinegar as in Germany is obtained from six tubs 

 eighteen feet high and four feet wide. 



By the quick process of Ham, when the fermentation is finished, the greatest 

 care ought to be taken that all access of air is excluded from the wash, and that its 

 temperature be reduced to, and maintained at, a heat below the point where acetifica- 

 tion commences. Those who, like Messrs. Hill, Evans, and Co., of Worcester, attach 

 great importance to the fabrication of the best-keeping vinegars, arc in the habit of 

 filtering the fermented wash, and also of storing it away for many months in a cool 

 situation ere it is passed through the acetificr ; and there cannot be a moment's doubt 

 concerning the great value of this practice, not only as regards the appearance and 

 flavour of the resulting vinegar, but also in respect to its dietetic and sanitary pro- 

 perties. 



All recently-fermented wash contains a quantity of partially-decomposed gluten, 

 some of which is mechanically suspended merely, but by far the Larger portion exists 

 in a state of solution through the agency of carbonic acid gas. 



A filter will remove the former, but time alone can dissipate the carbonic acid, and 

 lead to the deposition of the soluble gluten. At all events, time is the only available 

 remedy, for though heat would expel the carbonic acid, yet it would at the same time 



