[macfarlane] on the ANALYSIS OF CHEESE 9 



In this table the columns I, II, III, IV and V, represent the per- 

 centages obtained by the operations given in the preceding description 

 under the same numbers. Owing to the variations in the quantity of 

 moisture present in the dilïerent samples, a comparison of these with 

 each other is rendered somewhat difficult, especially as regards the ex- 

 tent to which the casein has undergone alteration. In order to bring 

 out this point more clearly, columns VII, VIII and IX, have been 

 added. The figure in VII consists of the sum of columns III, IV and 

 V, and may also be obtained by deducting the percentages of moisture 

 and fat contained in the sample from 100. It represents the casein and 

 the products of its alteration during ripening, and also includes the ash, 

 given separately in column VI. For the sake of convenience the name 

 of " Caseids" is given to this group of substances, using the term in a 

 sense somewhat analogous to that of " Proteids." Column VIII is 

 headed '• Caseones in Caseids,'" and indicatcb the percentage of the lat- 

 ter which is soluble in water, including the alcohol soluble, most of 

 which is also capable of being removed by water. The name "Caseone," 

 was applied by Duclaux to represent the products of ripening, but their 

 quantity was ascertained by a tedious process of aqueous extraction per- 

 formed on the original cheese, and by ascertaining and deducting the in- 

 organic constituents. Duclaux's figure would therefore differ from those 

 contained in column VIII, which not only include the ash proper of the 

 casein, but also the salt added in the process of manufacture. As an 

 index of the degree to which the process of ripening has extended in a 

 cheese the figures given in column IX, appear to be better applicable. 

 The alcohol seems to remove from the cheese less of the ash constituents 

 and the results in duplicates show a better agreement. The determina- 

 tion of "alcohol soluble caseone" is therefore proposed as a practical test 

 of the degree of ripening, and it is anticipated that it will be found to 

 bear a distinct relation to what is known by practical men as the "break- 

 ing down" of a cheese in the process of curing it. By reference to the 

 table it will be observed that the percentage of "alcohol soluble caseone" 

 in the caseids varies from 23.58 in the case of a Canadian cheese to 

 58.74 in the case of Camembert. It will also be seen that it is quite 

 high in the- case of " Hague," which is a Canadian cheese, evidently 

 made from skimmed milk. 



In order to obtain some idea of the nature of the substances ex- 

 tracted by alcohol and then by water from the dried and fat free con- 

 stituents of cheese, which have been called " caseids," determinations 

 were made of the nitrogen and ash contained in the extracts from certain 

 cheese samples, and Table 2 contains the results of this investigation. 

 In the analyses which this table contains, the caseids are calculated from 

 the total nitrogen of the cheese by using 6.35 as the factor for casein. 



