New York AGRICULTURAL EXPERIMENT STATION. 201 
more rapid development of cheese flavor and also more rapid devel- 
opment of objectionable flavors, especially when accompanied by 
higher temperature. Absence of salt in cheese is, in our experi- 
ence, invariably accompanied by the presence of bitter flavor, the 
intensity increasing with increase of temperature. Increased 
amounts of salt, other conditions being uniform, tend to a slower 
formation of cheese flavor. Excess of acid in cheese delays the 
development of cheese flavor, while the sour taste caused by the 
excessive acidity is seriously objectionable, especially in the early 
stages of ripening. 
(c) Relation of conditions of ripening to texture in cheese.— 
High temperatures in cheese-ripening favor the production of a 
crumbly, dry, mealy texture and also the formation of holes. Ex- 
cessive moisture with moderately higher temperature results in a 
texture of undesirable pasty softness. Excessive use of rennet- 
extract produces pasty texture. Large amounts of salt produce a 
texture that is dry, harsh and hard. Excess of acid acts much 
the same way. It is possible to overcome to some extent the faults 
of texture produced by excessive use of salt and acid by keeping 
the cheese for a long time in a moist atmosphere between 40° F. 
and 50° F. 
VI. THE ACTION OF ACIDS AND BASES ON CASEIN AND 
PARACASEIN. 
For more than fifty years there has been dispute over the ques- 
tion as to whether casein combines with acids to form insoluble 
casein salts of acids. When milk undergoes the process of ordinary 
souring or is treated directly by addition of an acid, the milk casein 
curdles or precipitates as soon as a certain amount of acid is reached. 
The view first expressed in 1780 by Scheele, who first isolated and 
studied lactic acid, was to the effect that the solid, white substance 
thus formed is a compound produced by the union of the acid with 
milk-casein. This view was disputed in 1843 by Rochleder who 
held that no definite chemical compound is formed when milk- 
casein is precipitated by am acid. Thirty years later Hammarsten 
devoted much attention to the subject and reached the same con- 
clusion as Rochleder. Different workers in later years have been 
divided between these two views, since no results have been so con- 
clusive as to settle the question beyond all possible doubt. 
(1) Insoluble products formed by action of acids on caseim and 
paracascin.— In 1901 a study of this subject was undertaken at this 
