Modification of Milk Casein and its Preparation as a Food.
Year: 1899

page_text: [Communicated from abroad by JOHN AUGUSTUS JUST, Chemist, of 109, West
Kennedy Street, Syracuse, New York, U.S.A.]
Modification of Milk Casein and its Preparation as a Food.
JAMES ROBINSON HATMAKER, Gentleman, 30, St. James's Square, London, S.W.,
do hereby declare the nature of this invention to be as follows:-
I take dry or moist milk casein or curd and remove all adhering traces of sugar
of milk therefrom by washing or other suitable way.
I then determine the degree of acidity of such curd in any suitable way.
I then make a suitable alkaline solution-such as a solution of bicarbonate
of soda at ordinary temperature and of only sufficient strength to neutralize
from one-half to two-thirds of the acidity of the curd, and in quantity sufficient
to give the mixture after the curd has been thoroughly dissolved a consistency
about like that of mucilage.
I mix the dry or moist curd-preferably in a somewhat finely divided state
-into the bath referred to and slowly and gradually heat the mixture to a
temperature of from 100 to 130 degrees Fahrenheit, and maintain it within those
limits until it becomes thoroughly homogeneous in character. To facilitate
this result the mixture is frequently agitated.
When this stage is reached the material is a sticky, uniform liquid of about
the consistency of mucilage.
Rendering it into a dry, light, flaky form is successfully accomplished by dis-
tributing a thin uniform film of the material over a suitably heated metallic
surface, drying it quickly, and removing it therefrom by a knife edge or by
brushes.
The product is a natural acid casein-(where bicarbonate of soda is used acid
sodium casein).
By neutralizing only a portion of the natural acidity of the casein, I enhance
the food value of the product as compared with wholly neutralized casein, and
make it more digestible.
Dated this Twenty-first day of January 1899.
JAMES ROBINSON HATMAKER,
Applicant.
JAMES ROBINSON HATMAKER, Gentleman, 30, St. James's Square, London, S.W.,
do hereby declare the nature of this invention and in what manner the same is
[Price 8d.]

page_text: to be performed, to be particularly described and ascertained in and by the
following statement:-
My invention has, reference to the modification of milk casein so as to make
it soluble and to a process for rendering it into light, dry, porous form in which
it can be preserved and used as a food-stuff.
Milk casein is naturally acid and insoluble in water, but, as is well-known, it
can be dissolved-except perhaps when it has been precipitated by rennet-
in various alkaline solutions and rendered soluble in water. I have found that
a more digestible product is obtained by neutralizing only a portion of its natural
acidity and I prefer so to modify it when it is to be used as a food, but my
process of drying its solution is independent of the degree of neutralization and
is suitable for drying any solution of casein.
To produce a food of the finest quality the raw casein or curd used should
be as nearly as possible free from sugar of milk and fat. I take such casein and
modify it and reduce it to solution as follows; I first determine its acidity in
any suitable way. I then make a suitable alkaline solution-such as a solution
of bicarbonate of soda-at ordinary temperature and of only sufficient strength
to neutralize from one-half to two-thirds of the acidity of the curd and in quantity
sufficient to give the mixture, after the curd has been completely dissolved, an
easy flowing consistency about like that of mucilage.
I mix the dry or moist curd-preferably in a somewhat finely divided state
into the bath referred to and slowly and gradually heat the mixture to a
temperature of from 100 to 130° F. and maintain it within those limits until
it becomes thoroughly homogeneous in character. Thus heating the mixture
facilitates the dissolving of the curd, but it is not absolutely necessary for the
curd will completely dissolve in a somewhat longer time in a bath of ordinary
temperature. But whether heated or not the mixture should be frequently or
continuously agitated until the curd is completely dissolved.. The solution will
then be a sticky, uniform liquid of easy flowing consistency.
In order to give an idea of the amount of bicarbonate of soda required, I may
say that from one to one and one-half pound added to twenty-two gallons of
water will make an alkaline bath which will modify and dissolve 150 pounds of
wet curd or about 100 pounds of pressed curd of average acidity.
Solutions of other alkaline reagents such as phosphate of soda, or caustic soda
or potash will modify and dissolve milk casein and may be used, and I wish it
understood that bicarbonate of soda is given in this specification purely as an
example of a suitable modifying and dissolving agent. Where other alkaline
reagents are used the quantities should vary from the quantity named in the
example given above in accordance with their relative alkaline strengths as com-
pared with bicarbonate of soda.
In my method of drying solutions of casein I employ a much higher degree
of heat than has heretofore been used in drying such solutions. I dry casein
solutions in a thin layer or film upon a surface which is heated to a temperature
slightly above that required to produce a free evaporation of their moisture.
212 to 220° F. is a good working temperature for such drying surfaces, but I
have found that a temperature of 2500 F. can be employed without injury to
the material.
I cause a very thin, uniform layer of the solution to be distributed over a
suitable metallic surface heated as above stated. The water of the solution is
rapidly almost instantaneously-driven off, leaving a thin, porous film of
desiccated casein, which may be removed by a knife-edge or by brushes. After
removal it may be reduced to a uniform powder by rubbing it through a fine
sieve.
In physical form the product thus dried is extremely light, dry and porous,
which greatly conduces to its ready solubility. It is sterilized in the process of
drying, is very preservable, and suitable for purposes of food.

page_text: Having now particularly described and ascertained the nature of my invention
and in what manner the same is to be performed, I declare that what I claim
is:-
1. Casein prepared in light, dry, porous form by the process of rapid drying
hereinbefore described.
2. The herein before described modification of casein prepared in light, dry,
porous form by the process of rapid drying herein before described.
3. The hereinbefore described process of drying solutions of casein which con-
sists in exposing a thin layer or film of such solutions to a temperature sufficiently
high to effect their rapid desiccation and sterilization.
4. The process of preparing casein as a food-stuff which consists in partially
neutralizing its natural acidity, bringing the partially neutralized casein into
solution, and drying the solution substantially as described.
Dated this 19th day of October 1899.