292 
Extracts from British and Foreign Journals. 
ON LIQUID RENNET, OR RENNET WINE. 
By William Procter, Junr. 
It has long been known that the mucous coat of the sto¬ 
mach of the calf, pig, and other young mammals possesses 
the power of coagulating the casein of milk, as in the making 
of cheese; but it is only of later years that an attempt has 
been made to introduce a solution of rennet^ as this substance 
is called, into pharmacy with a view to the cuisine^ as well as 
for use in medicine. For several pepsin, the proximate 
principle to which this coagulating power is attributed in an 
impure state, has been an article of commerce with a view to 
medicinal use in diabetes and other diseases; that prepared 
by M. Boudalt, of Paris, having acquired some celebrity. 
In several pharmaceutical works, recipes for making ^‘Li¬ 
quid Rennet may be found, but these vary much, both as 
regards the strength of the solution and the preservative in¬ 
gredients. The dried stomach of the calf prepared by salting it, 
and stretching it over a bent hoop to facilitate its desiccation, 
is familiarly known in the markets under the name of rennet, 
and most housekeepers prefer to keep and use it in this state, 
or by cutting this up and macerating it in wine; but for those 
who aim at manufacturing the solution for commerce, it is 
preferable to employ the recent membranes, both on account 
of economy and efficiency. 
Pepsin has never been isolated in a state of purity; it 
seems to be secreted by glands located in the mucous coat of 
the stomach, and, in connection with hydrochloric, and per¬ 
haps lactic acid, constitutes the active portion of what is 
called the gastric juice, concerned in the process of digestion. 
It is to this mucous coat of the organ, therefore, that attention 
must be given ; and inasmuch as the rennet tends to exercise 
its digestive power on the membrane itself, there is a pro¬ 
priety in using mechanical means to effect the rupture of the 
mucous coating to facilitate the extraction of the active prin¬ 
ciple without cutting it up, by malaxating them in water with 
salt, to which weak alcohol or wine is subsequently added. 
Some prefer at once to separate by the knife the mucous coat 
^vith the glands, but generally the whole organ is cut up, 
mixed with salt and water, and well malaxated at intervals. 
