An Improved Process for Producing Condensed Milk.
Year: 1899

page_text: Date of Application, 24th Aug., 1899-Accepted, 7th Oct., 1899
COMPLETE SPECIFICATION,
An Improved Process for Producing Condensed Milk.
I, AUGUST GÜRBER, Assistant at the Physiological Institute of the University
of Wuerzburg, Bavaria, in the Empire of Germany, do hereby declare the nature
of this invention and in what manner the same is to be performed, to be parti-
cularly described and ascertained in and by the following statement:-
The product hitherto known to the trade as condensed milk has the disadvan-
tage of greatly changing its taste, a circumstance which must be attributed to the
method of condensing by evaporation, employed in the manufacture of that pro-
duct. Another disadvantage lies in the fact that, owing to the milk being boiled
up to a comparatively slight degree of consistency, it does not keep in a good
state, so that it is necessary to allow a considerable addition of cane sugar. For
rearing infants, therefore, who require an addition of sugar varying according
to their stage of lactation this condensed milk is not at all suitable.
By the present method a condensed milk is produced not by evaporation, but
by an entirely new principle. It is well known that an aqueous solution of solid
substances if divided into minute particles becomes thoroughly frozen.
If this freezing process be effected in a centrifugal separator while rotating
the detached particles are thrown out according to their specific gravity, during
the act of freezing as well as during that of thawing, the detached particles flying
towards the circumference, where they form a solution, which is, say 5 to 6
times stronger than the original solution.
In order to work the new process for producing condensed milk, milk skimmed
by a centrifugal separator is put in the centrifugal drum and alternately caused to
congeal and thaw while being separated by the machine until the desired con-
centration has been reached, whereupon the superfluous water separated from the
concentrated milk having been removed, the milk is mixed again with the cream.
The inlet of cold and heat for purposes of congealing and thawing respectively
may be effected in any desired manner. The congealing however is preferably
accomplished from the interior of the centrifugal machine, whilst the introduction
of heat for thawing is effected from outside. The milk condensed in this manner
may be diluted with water to the original volume and still have the taste of fresh
milk without exhibiting the sweet, but to many people disagreeable flavour of
the condensed milk hitherto in use. This new condensed milk preserves its good
taste without the addition of sugar owing to its having been heated up to a high
degree in order to obtain the desired consistency.
For purposes of rearing infants, however, it may be mixed with sugar in any
desired proportion.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is-
The process for producing condensed milk, characterised by the feature that
skimmed milk is put in a centrifugal separator and there alternately caused to

page_text: freeze and thaw for the purpose, during the successive processes of congealing and
thawing of eliminating the superfluous moisture, and thereby attaining a high
degree of concentration, as herein described and set forth.
Dated this 24th day of August 1899.
S. S. BROMHEAD,
Patent Agent, 33, Cannon Street, London, E.C.