938 



Journal of Agricultural Research 



Vol. VI, No. 24 



sis. The fat in the jars was covered with a thin layer of paraffin to exclude 

 any action of the atmosphere other than that contained within the mate- 

 rial itself. All samples w T ere kept under the same conditions in cold 

 storage at a temperature of o° F. Samples taken from the lot packed 

 in jars were at once analyzed and, in addition, were scored by Messrs. 

 Corneliuson and Rabild, of the Dairy Division. After intervals of 

 approximately one month, samples were withdrawn from storage, 

 analyzed, and scored. This was continued for several months, during 

 which time a sufficient period had elapsed for the samples to manifest 

 any change which might occur in butter stored for a reasonable length 

 of time. 



As may be seen by reference to Table IV, it is certain that no altera- 

 tion in this sample of butter fat was manifested by the flavor. These 

 samples of nearly pure butter fat showed no physical alteration of any 

 kind after six months or even after one and one-half years in cold storage. 

 There was no development of any characteristic flavor whatsoever, the 

 scoring indicating what might have been expected in case of a material 

 deprived of nearly all its essential ingredients other than fat. 



Table IV. — Scores of butter fat stored at 0° F. 



As noted earlier in this paper, the following determinations were 

 made to establish a standard as a criterion for judging any change which 

 might occur in the fat of the same lot of butter (whole butter) prepared 

 with varying quantities of nonfatty ingredients (Table V). 



Table V. — Chemical constants of the butter fat after being nearly freed from the non- 

 fatty ingredients by melting, filtering, and washing and stored at 0°F. 1 



Age. 



Initial . . 



2 months 



3 months 



4 months 



Reichert- 



Meissl 

 number. 



■30.03 



3°- 17 

 29.84 

 29. 67 



Iodin 

 number. 



37-3° 

 37-42 

 36.58 

 36.68 



Saponifi- 

 cation 

 number. 



226. 8 

 226. 8 

 226. 9 

 226. 4 



Soluble 

 acids as 



butyric. 



Per cent. 



5-552 



572 

 483 

 140 



Insoluble 

 acids. 



Per cent. 



87-54 

 88. 10 

 87.52 

 87. 22 



Acetyl 

 value. 



3- 703 

 3-785 

 3-634 

 3- 340 



Free acid 

 as oleic. 



Per cent. 

 O. 45 6 

 .468 



.427 

 .408 



1 The determinations of chemical constants of the fat incorporated were made by Dr. E. G. Thomssen, 

 formerly of the Dairy Division. 



