1922.] PUBLIC DOCUMENT — No. 31. 31a 



Human Food. 



Deparimcni of MirrohioJof/i/. 



Project 1. " Microhiolojiical iiuestijjations in milk." 



Mr. AvEiiY and Mr. Xkill. 



The past year saw })ractical completion attend several 

 undertakings bearing upon the presence of Streptococci in 

 milk, and their relation to other Streptococci found in disease. 

 A report on one of these undertakings has been accepted for 

 publication in "Dairy Science." This deals with a study of the 

 groupings of Streptococci known as lactic Streptococci. 

 Another piece of work which is nearly ready for publication 

 consists of the study of these Streptococci in their relation to 

 growth conditions and reducing values upon methylene blue, a 

 reagent which has been employed for a number of years in 

 .certain dairy fleterminations. 



Another aspect of this study deals with the proteolytic 

 action of the lactic Streptococci as compared with other 

 Streptococci and their capacity to produce, particularly, amino 

 acids and ammonia. 



Project 3. " Canning investigations in the light of normal 

 and resistant organisms in continuous, fractional and pressure 

 methods of sterilization." 



Professor Marshall and Mr. McCrimmox. 



Further work on this project was done during the year in the 

 study of the thermal death point in connection with canning. 

 Progress, however, has been delayed through lack of the 

 necessary assistance. 



Agricultural Economics. 



Department of Acirlcnltural Economics. 



Project 1. "Local balance of trade in farm products." 



Assistant Professor Jefferson. 



This project was undertaken with a view to discovering 

 quantities of farm products produced and consumed in several 



