DETECTION OF LIME USED IN DAIRY PEODUCTS. 5 



ter is usually less than 0.2 per cent. The amount of iron or aluminum 

 found in the ash of uncontaminated products in the amounts taken 

 for analysis is negligible. The following data, taken at random from 

 a large number of determinations, show how closely duplicate deter- 

 minations of calcium oxid will check : 



Table 4. — Agreement in percentages of calcium oxid in ash of dairy products. 



Percentage 

 ofCaO. 



Perf'entage 

 of CaO. 



Percentage 

 of CaO. 



Percentage 

 of CaO. 



Percentage 

 of CaO. 



0. 03G0 

 .0372 



.0410 

 .0405 



0. 0500 

 .0500 



.0280 

 .0285 



0. 0575 

 .0600 



.0356 

 .0340 



0.0637 

 .0642 



.0425 

 .0410 



0. 0772 

 .0765 



.0567 

 .0562 



These figures show that with careful work results can be obtained 

 that check considerably within 0.003 per cent ; 0.01 per cent for salt- 

 free ash and 0.003 per cent for calcium oxid are considered the maxi- 

 mum differences allowable. 



Samples of milk collected in Denver gave figures comparable to 

 "those found in the literature, as shown in Table 5. 



Table 5.- — Analysis of Denver milks. 



Constituent. 



Jersey 



Holstein 



milk. 



milk. 



150 



3.30 



0.80 



0.75 



78.00 



66.50 



0.194 



0.165 



24.20 



22.00 



Unknown 

 milk. 



Fat (per cent) 



Ash (per cent) ■. 



Alkalinity of ash (ce N/10 acid per 100 grams) 



Calcium oxid in milk (per cent). 



Calciimi oxid in ash (per cent) 



4.00 

 0.73 



68.50 

 0.17 



23.30 



ANALYSIS OF UNNEUTRALIZED CREAMS. 



Analyses of a considerable number of creams received by local 

 creameries were made at the Denver laboratory of the Bureau of 

 Chemistry during the summer of 1913. The samples of cream, the 

 ash data of which are given in Table 6, were secured before neutrali- 

 zation. 



