EXPERIMENT STATION REPORTS. 



245 



that matter for ain* length of time, at a cold or even a cool temperature if 

 it is to be made into vinegar. The best temperature to maintain through- 

 out the vinegar fermentation process is about 75 degrees Fahr. 



"The contents of certain of the above barrels at the first analysis did 

 not contain sufficient acid, nor enough alcohol, to raise the percentage of 

 acidity up to market standard so an experiment was undertaken in a 

 small way to determine whether the addition of sugar and inoculation 

 with Sacch. eUipsoideus would have any effect in raising the percentage 

 of alcohol and consequently acid. Five hundred cubic centimeters of 

 each sample were treated as follows and inoculated with Sacch. eUipsoideus 



Karo was used on account of the sugar shortage. If no fermentation was 

 noted in the course of a few days, other additions of sugar were made. If 

 these results are any indication of those which would have been obtained 

 had sugar in some form been added to the contents of the several barrels, 

 then the addition of these amounts of sugar would have assisted consider- 

 ably in the ease of barrels Nos. 3 and 13, and greatlj' with barrels, Nos. 

 14, 19, and 28, while it would have been unnecessary with barrels Nos. 

 12 ancl 16. Unfortunately it is difficult to predict exactly just what will 

 happen in the barrel but if these few experiments can be taken at their 

 face value then the addition of sugar to weak vinegar followed by inocula- 

 tion with the desirable yeast*is^to^beTrecommended under^similar cir- 

 cumstances. 



"Honey vinegar of most excellent quality and high acidity has been 

 made by Prof. R. H. Pettit of the Entomological Division of this station 

 by diluting the honey, adding small amounts of peptone and potassium 

 phosphate for additional nutriment and inoculating with pure cultures of 

 Sacch. eUipsoideus and Bact. aceti. The elements contained in the chemicals 

 above named are very necessary for the rapid development of the j-east 

 but as they are not only hard to obtain in this form but expensive, ex- 

 periments have been carried out using a number of different combinations 

 of these same elements in a form which can be obtained readily and with 

 small expense at any drug store, comparing these results with those ob- 

 tained from the use of the more expensive ones. 



'The following formulae were used: 



I 



250.00 cc. diluted honey 

 1.18 gm. (XH4)9 SO4 

 0.20 gm. KH0PO4 

 0.025 gm. MgS04 



II 



250.00 cc. diluted honey 

 0.20 gm. KH2PO4 

 0.50 gm. peptone 



