Improved Baking Preparations.
Year: 1892

page_text: Date of Application, 17th May, 1892-Accepted, 18th June, 1892
COMPLETE SPECIFICATION.
Improved Baking Preparations.
I, JAMES YATE JOHNSON of 47 Lincolns Inn Fields, in the County of
Middlesex Gentleman do hereby declare the nature of this invention: (which has
been communicated to me from abroad by the Rumford Chemical Works, a
corporation constituted under the laws of the State of Rhode Island, U.S.A. and
having its principal place of business at Providence in the said State) and in
what manner the same is to be performed to be particularly described and
ascertained in and by the following statement :-
This invention relates to that class of baking preparations in which the active
acid agent is, either in whole or in part, some form of phosphoric acid, or acidulated
phosphate.
Under the general head of baking preparations may be included (1) the ordinary
baking powder, composed of a mixture of the phosphoric acid element with a
carbonate or bi-carbonate as active agents; (2) the phosphoric acid element when
put up alone, as is sometimes done, without the carbonate or bi-carbonate;
(3) preparations in which the phosphoric acid element and carbonate, or its
equivalent are put up in separate packages to be mixed before use; and
(4) preparations known as "self-raising flour," "quick raising flour," "prepared
flour" and by various other names, in which the phosphoric acid element and
carbonate are mixed by the manufacturer with flour in proper proportions for use
in making bread.
Broadly stated the present invention consists in the production of a baking
preparation in which the phosphoric acid element is in a practically uniform
granular condition free from pulverulent phosphatic material. This granular
phosphoric acid material constitutes a new product or article of manufacture,
possessing peculiar and distinctive properties and characteristics of great value for
the purposes stated, as is hereinafter explained.
As is well known preparations of the kind above referred to, as ordinarily
prepared, while possessing the highest dietetic value and leavening efficiency,
possess nevertheless, the property of serious deterioration, when freely exposed to
atmospheric humidity, compelling the manufacturer to employ extraordinary and
expensive means in packing to protect them from this influence.
Heretofore it has been the aim of the manufacturer to produce the phosphatic
element in the finest pulverulent condition possible, believing that thus, only,
could the highest efficiency be obtained. According to this invention however,
it has been discovered that the fine pulverulent condition of the commercial
phosphatic powders is not necessary to the highest efficiency in the leavening
quality, but is rather detrimental to it.
Indeed, the results of experiments have demonstrated that when a baking powder
having the phosphatic element in granular condition is used in place of one
containing that element mainly in fine pulverulent form, the leavening efficiency
of the preparation is materially augmented, while, at the same time, the
deterioration quality is reduced, if not entirely overcome. The reason for this
increased efficiency will be readily understood when the fact is taken into con-
sideration that, within limits, a somewhat slow evolution of the leavening carbonic
acid gas is desirable, in order that too much of it may not escape from the dough
during the mixing and kneading, before the loaf is placed in the oven; but rather
that a considerable part of it shall remain to be evolved during the baking process,
that the dough may be at its highest expansion when hardened by the baking
into the permanent cellular structure of the finished loaf. The slow evolution
quality is not possessed in a marked degree by phosphatic baking powder, as

page_text: heretofore prepared; and especially is it lacking when the phosphatic element
employed is of a highly acidulous character. This is due to the ready solubility of
the acid agent in its finely powdered condition, which of course, brings it into rapid
reaction with the alkaline bicarbonate, and causes the rapid evolution of its gas.
When, on the contrary, the particles of the acid are in a coarse condition, solution
and consequent reaction are retarded. In practice it has been found, therefore,
that by giving to the phosphatic element of the baking powder a uniformly coarse
condition, the property of slow evolution of the gas is increased, and a consequent
marked increase in baking efficiency is obtained. In this respect therefore, the
new product, possesses a distinct advantage over phosphatic powders heretofore
made and used.
As is well known acidulated phosphates possess naturally a high deliquescent
property, and this to such a degree, when reduced to a finely powdered state and
exposed to variable atmospheric conditions, that they at times greedily absorb
moisture, and thereby acquire of themselves alone (or impart to any mixture of
powders of which they form a considerable proportion) a sticky, clammy condition.
This absorption of moisture by the acid element when packed separately in the
usual fine condition, causes a recrystallization of the powder, which in such cases
hardens into a caky, crystalline mass, unsuitable for the use intended. Moreover,
such a powder or mixture of powders, is difficult to pour either into or out of any
small necked receptacle, and is especially difficult to measure out in the quantities
in which baking powders are used.
This objectional quality in phosphatic powders it has been found does not attach,
to any serious extent, to the new granular preparation. The reason for this improve-
ment is plainly apparent when the fact is taken into consideration that, in the same
weight of material, the surface exposed to the atmospheric influence is greatly
increased, the finer its pulverulent condition.
According to this invention it has been furthermore discovered that, in phosphatic
baking powders as heretofore prepared, the deterioration quality largely due to
the exceedingly fine pulverulent condition of the acidulated element, and it has
'been demonstrated that this is true by comparing a baking powder having its
phosphatic element in granular form, essentially free from all finely pulverulent
phosphatic material, with other like preparations having the phosphatic element
in their mixture in the usual powdery condition, with the result that the latter were
practically spoiled, while the former, shewed little, or no deterioration.
The improved keeping quality of baking powder mixtures containing the
acidulated phosphates in a uniformly granular condition is due partly to the
reduced deliquescent property of the acidulated material in such condition, already
referred to, and partly to the greatly reduced number of points of contact which
such granular acidulated material presents to the carbonate with which it is in
admixture, in proportion to the weight employed. Another reason for this
improved result is the increased size of the interspaces between the active
particles, due to this granular condition, which permits, when a fine diluent is
employed, of a more complete introduction of the diluent between these particles
and their isolation from each other.
To prepare the acidulated phosphate in this improved granular condition, the
following is the proceeding. The material, as ordinarily prepared for the grinding
process is taken and passed through any suitable mill, and ground to a rather
coarse condition, and then it is bolted through as coarse a bolt as its proper baking
efficiency will allow. For most preparations of this kind, it has been found that a
No. 9, silk bolt answers the requirement.
This bolted product from the No. 9, silk bolt, is then subjected to another
bolting process, using a much finer bolt for this purpose. A No. 16, silk has
given excellent results for this. The material should be continued long enough in
this No. 16, silk to completely remove all the fine material that will pass through it.
The process may be much facilitated by using knockers, or aspirators, if the
condition of the material so requires. The material which will not pass the

page_text: No. 16 bolt is a mass composed entirely of granules practically uniform in size, and
this may be put up for use and sale in any of the ways above indicated. The
material passing through the No. 16, if no other use be found for it, may be used
as a drier in the crystallization of new batches of the phosphatic material, and no
loss be incurred from this source, except the double handling involved.
It is evident that any other suitable method of producing the phosphatic material
in granular form may be employed, and the resulting product possess equally
valuable qualities, and therefore I do not restrict myself to the method described,
nor to the particular size of the granules set forth.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A baking preparation containing phosphoric acid, or its compounds, in
granular condition essentially free from pulverulent phosphatic material, sub-
stantially as hereinbefore described.
2. A baking preparation composed of a phosphoric acid element in granular form
essentially free from pulverulent phosphatic material, in admixture with a carbonate
or bi-carbonate, as hereinbefore set forth.
LM 1900
J. H. JOHNSON & Co.,
Agents.