An Improved Process of Deodorizing Oils and Fatty Substances.
Year: 1897

page_text: Date of Application, 10th Nov., 1897-Accepted, 8th Jan., 1898
An Improved Process of Deodorizing Oils and Fatty Substances.
I, DR. CHARLES CULMANN, of No. 23 Alter Gröningerstrasse, Hamburg, in the
Empire of Germany, Trade Chemist, do hereby declare the nature of this invention
and in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement :-
This process for deodorizing oils and fatty substances enables the usual beating or
"stirring "during which acids and lyes are generally added,-and the tedious
washing, to be dispensed with; the formation of emulsions, which invariably takes
place with disturbing effect in the course of the purification of train oil (blubber, cod-
liver oil or the like), to be avoided, and the oil or fat to be purified or refined in one
single, considerably simplified operation.
These advantages are attained mainly by subjecting the oil or fat simultaneously
to the action of bodies whose reaction is acid (especially alum or aluminium
sulphate) used in the condition of a saturated solution, and to the influence of
superheated steam.
In order to obviate a dilution of the chemicals employed and the formation of an
emulsion in this process, the oil or fat to be deodorized is, further heated externally,.
or prevented from cooling by thermal insulation, while the steam sent through is so
controlled that the proportion of water contained in the material which is being
treated either remains constant or diminished..
The following is an example of the performance of the process in practice.
100 kilogrammes of oil are mixed with from 2 to 4 per cent. (according to the
nature of the oil) of a cold, saturated, aqueous solution of alum or aluminium sulphate,
and treated with steam at a temperature of from 108 to 110 degrees Centigrade.
The combined action of steam at that temperature, and of the chemicals named, will
effect the separation of the offensive matter, partly in the form of a gluey mass and
partly in a volatile condition; the latter portion being carried away by the steam. Thus
the impurities will be removed without in the least affecting the oil itself.
In order to prevent any of the steam from being condensed, and the solution of the
chemical agent employed from becoming more dilute in consequence, as such a
dilution would necessarily result in an emulsion, the receiver should, during the
operation, be surrounded by a bad heat conductor, or be heated, while the circulation
of the steam at from 108 to 110 deg. Centigrade should be so regulated that the
amount of water present should tend to diminish, rather than increase.
After the steam-circulation has been kept up for from two to four hours, and
when the last trace of an offensive odour has disappeared, the steam is cut off and
the oil is left standing at rest. Then, almost instantaneously, the oil will neatly
separate from the solution of its own accord, without any emulsion forming, so that
the pure oil may be drawn off a very short time after.
The oil is allowed to deposit its sediment in the receivers, which are maintained at
a temperature of about 80 degrees Centigrade and it will be found to clear compara-
tively quickly, the final product being a perfectly limpidand inodorous oil. In fact it
will resume none of its former nauseous odour even if it should be heated, which
some of the apparently inodorous fish-oils do; so that any subsequent washing or
filtering becomes unnecessary.

page_text: The process described is essentially serviceable in deodorizing whale and seal
blubber, cod-liver oil or the like; and it also may be extended to other fats, especially
the various sorts of tallow. By it, odourless and tasteless oils may be prepared (with
or without the co-operation of heat), which will in their properties or behaviours
prove exactly similar to the oils obtained by boiling lard.
One main advantage, which this process offers to manufacturers, is, that he is no
longer under the necessity of working the fat of animals immediately after collecting
it, in order to produce the finer kinds of oil.
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 :-
1. A process for deodorizing oil and fat, mainly consisting in subjecting the oil or
fat simultaneously to the action of chemicals having an acid reaction (more especially
alum or aluminium sulphate) in the state of a saturated solution, and to the action
of superheated steam.
2. In the process referred to in the 1st claim, with a view to avoiding the dilution
of the chemicals and the formation of an emulsion, subjecting the substance under
the treatment to external heating or thermal insulation and admitting the steam
under such conditions that the proportion of water contained in the material does
not increase.
HASELTINE, LAKE & Co.,
45 Southampton Buildings, London, W.C., Agents for the Applicant.