IMPROVEMENTS IN MAKING BREAD
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by the said Andrew McDonald at the
Office of the Commissioners of Patents on the 3rd October 1883.
_ANDREW MCDONALD of Glasgow, in the County of Lanark, North Britain
"IMPROVEMENTS IN MAKING BREAD
"
This Invention relates to improvements in making bread.
Hitherto cream of tartar and tartaric acid have been used in the manufacture of
bread, these substances forming tartrate of soda. in the compound, which I consider
to be injurious to the system.
Instead of cream of tartar or tartaric acid I use the acid or bisulphate of potash
or of soda (the acid or bisulphate of potash by preference) prepared in any way
suitable for the purpose and amalgamated with the dough in the manner in which
cream of tartar or tartaric acid have hitherto been used.
The acid bi-sulphate of potash used under this Invention is preferably obtained
by treating pure nitrate of potash with sulphur sulphuric acid in manufacturing
nitric acid or vitriol. The bye-product thus obtained would be a pure acid sulphate
of potash ready for use:-Or pure nitrate of soda may be treated in the same way
with sulphur sulphuric acid thus producing a bye product of pure acid sulphate of
soda for the purposes of this Invention.
These bye products of potash and soda may be afterwards crystalized either with
or without the addition of sulphuric acid-or, when crude materials are used in the
manufacture of nitric acid or vitriol the bye-products herein before mentioned may
be crystalized in the same way to remove impurities.
Under another mode the normal sulphates of potash and of soda may be fused
with sufficient sulphuric acid added to produce the bisulphates of acid sulphates of
potash and soda for the purposes of this Invention.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Andrew McDonald in the Patent Office on the 2nd April 1884.
ANDREW MODONALD of Glasgow in the County of Lanark, North Britain.
IMPROVEMENTS IN MAKING BREAD
My said Invention relates to improvements in the process of making bread, cakes, 5
biscuits, puddings, and the like.
Hitherto cream of tartar and tartaric acid have been so used, these substances
forming a salt difficult to dissolve and which I consider to be injurious to the
system.
Instead of cream of tartar or tartaric acid I use the Acid or Bi-sulphate of Potash 1
or of Soda (the Acid or Bi-sulphate of Potash by preference) as I find these Acids
or Bi-sulphates besides being much cheaper are much more easily dissolved than
the salts of Cream of Tartar or of Tartaric Acid.
The Acid or Bi-sulphate of Potash or of Soda which for the purposes of this
Invention is preferably used in the anhydrous state of these salts may be prepared 1
in any suitable way and amalgamated with the flour or with the dough in any of
the modes in which Cream of Tartar or Tartaric Acid have hitherto been used.
As compared with the other ingredients the proportion of Bi-sulphate may be as
follows, namely, to 8 pounds of flour
and 1 ounce of Bi-carbonate of Soda or of Potash
1 ounce of Bi-sulphate of Potash or of Soda
or if butter milk, or sour milk, is used in making the bread, cakes, biscuits,
puddings, or the like to 7 pounds of flour
and 1 ounce of Bi-carbonate of Soda or of Potash
1 ounce of Bi-sulphate of Potash or of Soda.
Obviously instead of Bi-carbonate of Soda or of Potash the Carbonates of these
substances may be employed with the foregoing mode of using Bi-sulphate of
Potash or of Soda, in which case about double the quantity of Carbonate as
compared with Bi-carbonate would be required.
2
2
It is to be understood although I have given the above proportions of the 3
Bi-sulphates as being those which I find well adapted and satisfactory for general
use that I do not confine myself to them and that they may be modified without
departing from the main or essential features of my said Invention, which are in
the making of bread, cakes, biscuits, puddings and the like to provide a cheap
substitute for Cream of Tartar or Tartaric Acid and one whose salts are more easily
dissolved than the salts of these substances.
Generally wherever Bi-sulphate of Potash or of Soda is substituted for cream of
Tartar, half the quantity of the Bi-sulphate as compared with Cream of Tartar will
suffice, and when the Bi-sulphates are employed instead of Tartaric Acid they may
be used in quantities equal to the quantities heretofore used of Tartaric Acid.
The Acid Bi-sulphate of Potash for employment under this Invention may be
obtained in any of the usual methods but it is preferably procured by treating
pure Nitrate of Potash with Sulphur Sulphuric Acid in manufacturing Nitric Acid
or Vitriol The bye product thus obtained is a pure Acid Bi-sulphate of Potash
which after being ground to a powder by any suitable means is ready for use.
Pure Nitrate of Soda may be treated in the same way with Sulphur Sulphuric
Acid thus producing a bye product of pure Acid Bi-sulphate of Soda for the
purposes of this Invention which after being ground to a powder is ready for use.
These bye products of Bi-sulphate of Potash and Soda may be crystallized either
with or without the addition of Sulphuric Acid. When crude materials are used

page_text: in the manufacture of Nitric Acid or Vitriol the bye products (Bi sulphate of Potash
and of Soda) may be crystallized in the same way to remove impurities.
Under another mode the neutral sulphates of Potash and of Soda may be fused
with sufficient Sulphuric Acid added to produce Bi-sulphates or Acid Sulphates of
Potash and Soda for the purposes of this Invention.
When the Bi-sulphate of Soda is used for the purposes of this Invention as it is
more deliquescent than the Potash salt, in order to preserve it in a proper condition
for employment it is preferably mixed with a sufficient quantity of rice flour or
farina to prevent it caking
Having now described and particularly ascertained the nature of my said
Invention and systems or modes in or under which it is or may be used or carried
out in practice I would observe in conclusion that I do not claim any móde of
manufacturing Bi-sulphate of Potash or of Soda nor do I confine myself to the use
of these Bi-sulphates when obtained by the modes hereinbefore described but what
I desire to claim and secure by Letters Patent is,
The use of Bi-sulphates of Potash and of Soda as a substitute for Cream of
Tartar or Tartaric Acid in making bread, cakes, biscuits, puddings and the like,
substantially as described.
In Witness Whereof, I, the said Andrew MoDonald have hereunto set my hand
and seal, this First day of April in the Year of our Lord one thousand eight
hundred and eighty four.
ANTA