EXPERIMENT STATION REPORTS. 



249 



"During the alcoholic fermentation the colloids which make the whey 

 cloudy are separated out and after inoculation with Bad. aceti when a con- 

 siderable amount of acid is present, the whey becomes very clear and is 

 of a light straw color. The taste of whej^ vinegar resembles that of 

 whey soured by Bad. bulgariciim and is not wholly pleasant to mj^ taste 

 at least. It is quite evident that the addition of sugar is necessary, 

 and whether under these circumstances the manufacture of whey vinegar 

 would be of economic value is a question. 



"Pure cultures for vinegar making were instituted in 1910 at this 

 laboratory. However, the August 1918 quarterly bulletin contained 

 the first advertisement put out for some time, that the College Bacterio- 

 logical Laboratory could furnish such pure cultures. That there was a 

 call for some such thing to make vinegar-making successful is evidenced 

 by the orders for cultures. At first the yeast and bacteria necessary 

 for the vinegar fermentation were sent out in a combined culture, for 

 twent3'-five cents a culture, but experience has proven that in realit^^ the 

 so-called vinegar fermentation is two successive fermentations, the second 

 depending on the first, and the organisms (j^easts) of the first stage of 

 the vinegar process were hindered in their activities, often checked en- 

 tirely even by the presence of the ^^neg•ar bacteria and their products. 

 Consequent!}' it was considered a wise step not to continue sending out 

 mixed cultures, so beginning with the j^ear 1919, the wine yeast and vine- 

 gar bacteria were sent out separateh' for twenty five cents per culture. 



"The following is the report of vinegar cultures sent out from August 20, 

 1918 to June 25, 1919 inclusive. 



"As yet a very few reports have been received from those using pure 

 cultures, some are favorable and others are unfavorable as would be ex- 

 pected. 



"Thirty analyses were made of cider or of vinegars which were not 

 attaining sufficient acidity, and upon the results of these anah'ses, ad- 

 vice was given for treatment. The table showing these results follows: 

 (The Hort. Dept. vinegar is not included in these results). 



