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stuffs prepared from it; (2) on the cstimatiou of fat in linseed cake; 

 (.)) on the behavior of fat toward animal charcoal. 



The dairy division has made analytical studies of the morning's and 

 evening's milk of ten cows and of the milk of different breeds; exam- 

 inations of butter fat and of the percentage of water in Schleswig- 

 Holstein butter, and experiments with the Danish hand-centrifuge. Of 

 the 158 samples of milk sent to the station for analysis 18 were found 

 to have been watered and 21 to have been partially skimmed or diluted 

 with skim milk. Twenty-five per cent of the samples, therefore, weie 

 found to liave been tami)ered with, and 11 others Avere suspected. 

 It is proposed during the present year to make experiments on the 

 determination of solids in milk; on the value of fluorine salts, especially 

 sodium fluoride, as a milk an<l butter preservative; studies of the albu- 

 minoid materials in "stringy'' milk; and feeding experiments with 

 milch cows. 



Among the investigations of the bacteriological division were studies 

 of the use of pure cultures of bacteria in ripening cream. This use of 

 pure cultures is analogous to their use in the manufacture of spirits, Avhere 

 their introduction has been attended with marked success. A prelimi- 

 nary experiment, made in February, 1890, Avas followed by encouraging- 

 results. More extensive experiments w^ere then made to determine 

 whether the project was i)racticable on a large scale and whether the pure 

 cultures could be retained practically pure for any considerable length 

 of time. The material for inoculation of the fresh cream was taken 

 each time from the buttermilk of the previous churning, and it was 

 found that in this way relatively pure cultures could be retained for 

 about 14 days. In later experiments in a large creamery it was recom- 

 mended to transplant the bacteria by usin g a sma 11 a m on n t of the ripened 

 cream, and this was found to work successfully. As to the possil)ility 

 of eliiuinatiug numerous undesirable qualities of butter by the use of 

 pure cultures of lactic-acid bacteria, tests which were made showed at 

 once a favorable change in the quality of the butter, and indicated that 

 these faults could be prevented by the use of i)ure cultures. The sta- 

 tion has also distributed pure cultures, and in each case has requested 

 that a report be made of the results of their use. In cases where the 

 butter Avas oily, possessed a musty or an oily flavor ("beet taste"), or 

 was generally poor, the use of these cultures has been attended bj' a 

 marked improvement in aroma and quality of the butter. Several 

 critical examinations of butter Avhich possessed undesirable qualities, 

 such as a decidedly oily consistence, a strong, acid flavor, and other 

 disagreeable flavors, shoAved the presence of large quantities of yeasts 

 and molds of A^arious forms in every instance. 



Studies of the causes of the formation of caAnties in cheese indicated 

 that this Avas due to bacteria a\ hich are capable of decomposing the milk 

 sugar (and perhaps also the albuminoids) and thus CA^ohang gases. 

 The size of the caA'ities and the character of the gases depend upon 



