New York AGRICULTURAL EXPERIMENT STATION. 269 
BEHAVIOR OF SALT-SOLUBLE AND ALCOHOL-SOLUBLE PREPARATIONS 
TOWARD ACIDS. 
In d2termining the amount of acid that could combine with 
these salt-soluble and alcohol-soluble preparations made from 
cheese, we used the methods already employed in connection with 
casein and paracasein. We suspended .5 gram of proteid in 
water, added 10 cc. of *. hydrochloric acid, made the volume 
100 
to 100 ec. filtered, and titrated the filtrate with —*_ sodium 
100 Ss 
hydroxide, with phenolphthalein indicator. The results, figured 
on the basis of one gram of proteid, were as follows: 


TABLE V.—ACID COMBINING POWER OF DIFFERENT PREPARATIONS. 


Amount of | 4 cid equal to|Acid equal to 


MATERIAL USED. c acid used |"n-100 HCl injn-100 HCl in 
n-100 H Cl. filtrate. proteid. 
: f ce. cc. cc 
amar TEC IGASEIN aes ok een) os heeds ste 6 rd omg, Bak, ok 20.0 13.6 6.4 
Alcohol-soluble preparation..................2.5: 20.0 13.6 6.4 
Steno DO sore ara TOs hei ob op hes cans eindtiel chess beets 20.0 14.0 6.0 





In respect to the power of combining with acids, these results 
indicate that the alcohol-soluble and salt‘soluble preparations 
made from cheese are essentially the same compounds as casein 
and paracasein, that is, that they are essentially base-free para- 
casein. 
THE NOMENCLATURE OF CASEIN AND PARAGASEIN 
AND THEIR COMPOUNDS. 
From the work presented in the preceding pages, there is rea- 
son to believe that there exist the following bodies, representing 
milk-casein and paracasein and the compounds formed by them: 
Casein, the base-free proteid or free casein. 
Basic calciwm casein, containing free casein combined with 
about 2.40 per ct. of CaO. 
Neutral calcium casein, calcium casein containing about 1.50 
per ct. of CaO in combination, probably identical with casein as 
it exists in cows’ milk. 
Casein salts of acids, compounds existing as precipitates and 
formed by combination of the free proteid with acid. 
Paracasein, the base-free proteid formed by treating calcium 
casein with rennet enzym. 
