sept. ii. i 5l 5 Progressive Oxidation of Cold-Storage Butter 



943 



Table XI. — Chemical constants of the fat of normally washed butter, with medium con- 

 tent of nonfatty ingredients , stored at o° F. 



[Protein, 0.57 per cent. Total, NX6.38] 



There is practically no variation in these figures from those obtained 

 in the foregoing determination of chemical constants with the nearly 

 pure butter fat standard. Evidently the fat in these two samples of 

 butter underwent little or no chemical change, owing to the presence 

 of either the confined air or the other nonfatty components. The analysis 

 of this confined air, however, gave figures which differed considerably 

 from those obtained in the analysis of the air confined within the samples 

 of the butter fat itself (Table XII). 



Table XII. — Analysis of air in excessively washed butter, with low content of nonfatty 



ingredients, stored at 0° F. 



[Calculated to 0° C and 760 mm. Protein, 0.50 per cent. Total, NX6.38] 



Age. 



Months 

 2 .'. . . . 



3 



4 



5 



14 



Total gas. 



C.c. 



31.88 

 42- 5° 

 26.57 

 26.28 

 30.55 



Total carbon dioxid. 



Per cent. 

 I4.05 



6. 52 



7-57 

 7-38 

 5-7° 



Total oxygen. 



5-5 2 

 6.47 



3-39 

 3- 24 

 1.84 



Per cent. 

 17.31 

 I5-23 

 12. 76 



12-33 

 6. 03 



Calculated 

 oxygen. 1 



C.c 



5 

 7 

 4 



4 



5 



1 After deducting figure for carbon dioxid from total quantity of gas extracted from the tube and assuming 

 that the residual gas is pure air — that is, approximately one-fifth oxygen. 



Table XIII. — Analysis of air in normally washed butter, with medium content of non- 

 fatty ingredients, stored at 0° F. 



1 After deducting figure for carbon dioxid from total quantity of gas extracted from the tube and assuming 

 that the residual gas is pure air— that is, approximately one-fifth oxygen. 



There is no great difference in the total quantity of carbon dioxid to be 



observed between these samples of excessively washed butter and what 



is considered to represent normally washed butter. It is to be noted 



that there is very little difference in the protein content of these two 



55852°— 16 2 



