706 EXPERIMENT STATION EECOED. 



The readiness with which milk absorbs odors from the air was 

 early demonstrated by station workers and led to radical reforms in 

 methods of milk production and care. The discovery of the value 

 of the covered and the small-topped milk pail was a consequence 

 of the experiments at the Connecticut Storrs Station and elsewhere, 

 demonstrating that dirt particles and bacteria from the cow's body 

 and the air found their way into the milk. That feeding after milk- 

 ing, washing and clipping the cow's udder and flank, and other aseptic 

 measures all aided in the production of a cleaner and more sanitary 

 milk, was also indicated. The accumulated results of such studies 

 as these pointed to the cow as a leading source of infection and 

 logically led to effective and practical remedies. The importance of 

 prompt and efficient cooling of milk followed studies of the tempera- 

 ture relations of dairy bacteria, and has become a part of good prac- 

 tice. The effect of milking machines on the germ content of the milk 

 has been studied by various institutions, and the necessity of exer- 

 cising proper precautions, especially in washing and cleansing all 

 parts, has been amply demonstrated through practical trials. 



The subject of pasteurization has received no little attention from 

 the Dairy Division and from many station workers. The pasteuriza- 

 tion of milk in the bottle has recently been found to be entirely feasi- 

 ble and to be even more efficient in reducing the bacterial content of 

 milk than the customary " holder " sj'^stem of pasteurizing. The rela- 

 tion of proper pasteurization as an efficient safeguard against the 

 spread of communicable diseases has likewise been shown in both a 

 scientific and a practical way. Aside from the effects of pasteuriza- 

 tion in reducing the bacterial content of milk, the influence of heat 

 upon the composition and properties of milk has received attention, 

 notably that upon the viscosity of milk and the proteids and fat 

 globules. 



The sources of bacteria in milk have been studied as well as the 

 fermentations produced by various species. Particular attention has 

 been paid to the prevention of bacterial contamint^tion, and methods 

 of destroying or delaying the development of the organisms that do 

 gain access to milk have been repeatedly tested. Much valuable in- 

 formation has been acquired, but as was pointed out by Rogers at this 

 meeting, bacteriology is still a young science with a constantly chang- 

 ing technique and frequent discoveries of unexplored fields. This is 

 illustrated by the experience with the bacterial count as an indicator 

 of pollution. For some years, it has been generally assumed that 

 the bacterial content is a measure of the sanitary quality of milk, 

 and the plate method a measure of the bacteria. Recent tests, how- 

 ever, have indicated in the opinion of Professor Stocking, that " ex- 

 treme liberality must be used in the interpretation of the plate count, 



