500 



STATE BOARD OF AGRICULTURE. 



In the conversion of alcohol into acetic acid 100 parts of alcohol 

 should yield theoretically 130 parts of acetic acid, but less than 120 

 parts are actually obtained because certain other yeasts and bacteria, 

 which are quite sure to be present, also use alcohol as food. 



Thus for every 100 parts of sugar present in the original sugary solu- 

 tion under favorable conditions, 50 to 55 parts of acetic acid should be 

 obtained. So if a vinegar containing 5 per cent acetic acid is desired, 

 the fermentation should be started with at least a 10 per cent sugar 

 solution, while for a 1 per cent acetic acid content (Michigan standard) 

 the sugar solution (fruit juice, etc.) must contain at least 8 per cent 

 sugar. (See Table I.) ■ 



Fig. 2. Photograph of Vinegar Bacteria. Magnified 2,000 times. These bacteria secrete a gela- 

 tinous material which binds them together and produces the membrane known as "mother of 

 vinegar." 



IMPORTANT rOINTS IN VINEGAR MAKING. 



Use of a saccharimetcr: In order to know that the sugar in the freshly 

 pressed fruit juice, freshly diluted sugar, syrup, molasses, honey, etc., is 

 of sufficiently high percentage to make ultimately vinegar of market 

 standard, it is necessary that a saccharimeter or hydrometer for sugar 

 be used. This is merely a hydrometer, reading directly in percentages 

 of sugar, and is indisj)eiisab]e if you Avisli to start your vinegar i-iglit. 



Brix or Balling's hydrometers read directly in percentages of sugar 

 but Beaume's hydrometer scale readings are somewhat different so if 



