2 



BULLETIN 524^. U. S. DEPARTMENT OF AGRICULTURE. 



prevent excessive souring, to " lime " or " neutralize " cream of high 

 acid content, before pasteurization, in order to reduce its acidity and 

 improve the salable quality of the butter made from it. Some 

 creameries use sodium carbonate for this purpose instead of lime. 



The TTork reported in this bulletin was undertaken for the puri^ose 

 of developing and perfecting a method for detecting with certainty 

 the addition of lime to cream before its manufacture into butter. It 

 is believed that no such method has heretofore been published. The 

 detection of alkali salts when used to neutralize dairy products has 

 not been considered in this publication but has been left for future 

 work. Nor has any consideration been given to the question of pos- 

 sible detriment to health, or to the legal, economic, and ethical phases 

 of the process discussed in this bulletin. 



Milk and products derived from milk contain calcium phosphate 

 as one of the principal constituents of the ash. Leach ^ states that 

 the percentage of calcium oxid in the ash of a typical milk is 20. 

 Blj^th^ gives figures ranging between 17.31 and 27.55 with a mean 

 of 22. Tibbies ^ quotes an analysis by Schrodt wherein the calcium 

 oxid is 21.45 'per cent of the ash. Konig * gives a figure of 22.42 per 

 cent. Kostler^ reports values for the percentages of calcium oxid 

 in the ash of milk, cream, buttermilk, and butter. His maximum 

 and minimum figures are given in Table 1. 



Table 1. 



-Percentages of calcium oxid i/n the ash of dairy products, as 

 calculated by Kostler. 





Number 



of 

 analyses. 



Calcium oxid in ash- 



Substance. 



Maxi- 

 mum. 



Mini- 

 mum. 



Milk , 



10 

 1 

 1 



19 

 11 



Per cent. 

 24.63 

 24.48 

 23.09 

 24.54 

 22.83 



Per cent. 

 22.24 













21.22 



Butter 



20.07 







Shaffer and von Fellenberg^ found values between 18.3 and 20.2 

 per cent for butter. 



1 Leach, Albert E., Food Inspection and Analysis, 3d ed., p. 128, New York, 1913. 

 " BIyth, A. W. and M. W., Foods : Their Composition and Annlysis, p. 201, London, 

 1909. 



* Tibbies, William, Foods, Their Origin, Composition, and Manufacture, p. 245, London, 

 1912. 



•* Konig, J., Chemie der Menschlichen Nahrungs- und Genussmittel, 4th ed., v. 2, p. 603, 

 Berlin, 1904. 



* Kostler, G. Zur Charakterisierung unserer schweizerischen Butterarten. Jn Landw. 

 Jahrl). der Schweiz, 25 (1911), 249-276. 



8 Shaffer, F., and von Fellenberg, Th. Zur Unterscheidung der Butterarten. In Mitt. 

 Lebensm. Hyg., 2 (1911), 220. 



