EXPERIMENT STATION BULLETINS. 499 



shall, upon conviction, be punished by a line of not more than two 

 hundred dollars or imprisonment in the county jail not to exceed six 

 months or both such fine and imprisonment in the discretion of the 

 court." 



THE VINEGAR FERMENTATION, 



The vinegar fermentation is in reality two distinct fermentations, 

 one following the other. The first, the formation of alcohol from sugar 

 is accomplished by alcohol-producing yeasts of which Saccharomyces 

 ellipsoideas is the best example. Th«se yeasts change the sugar into 

 alcohol according to the following chemical equations: 



Sacch. 

 C12H22O11 + HoO + ellipsoideus = 2C6Hio06 



Complex'sugar -j- Water -f Yeast = Two simple sugars. 



Then the simple sugars are changed into alcohol as follows : 



Sacch. 

 CeHi.Oo + clUpsoidcm = 2C0H5OH + 300, 



Simple sugar -\- Yeast = Alcohol -f Carbon dioxid (gas). 



The sugars in most fruits and in honey are largely simple sugars, 

 while the sugars derived from grains, cane sugar, syrups and molasses, 

 from sugar beets, and from maple syrups, consist largely of complex 

 sugars. 



Besides sugar, of which the solids in cider largely consist, the chemi- 

 cals represented by the acidity and ash just mentioned in the state law, 

 are quite necessary for the yeast to carry on the alcoholic fermentation 

 as also they are for the subsequent acetic fermentation. The acidity of 

 cider is due mainly to malic acid, which serves to check the development 

 of putrefactive bacteria. The ash, consisting largely of potassium salts 

 and salts of other minerals, furnishes the mineral elements which are 

 as necessary to microbial as to human foods. For the best results 

 this first stage, i. e., the alcoholic fermentation should be kept rigidly 

 separate from the next stage in vinegar formation, the acetic fermen- 

 tation. 



The second fermentation in vinegar production, the formation of 

 acetic acid from alcohol, is accomplished by the vinegar bacteria, of 

 which Bacterium accti is the most prominent type. These vinegar 

 bacteria of which the "mother of vinegar" consists largely, need the 

 oxygen of the air in order to change the alcohol into acetic acid, as 

 is shown hj the following chemical equations : 



an.OH + 0„ + Bact.aceti = CH3COOH + HoO 



Alcohol 4- Oxygen -f Vinegar bacteria = Acetic acid + Water. 

 (air) 



Yield of Vinegar: In these fermentations 100 ])arts of sugar in the 

 juice should produce theoretically about 51 parts of alcohol; that is, 

 about half as much alcohol by weight should be obtained as there was 

 sugar in the juice. In actual practice only from 45 to 47 per cent is 

 obtained because some of the sugar is used by Sacch. ellipsoideus and 

 other microorganisms for purposes other than alcohol production. 



