Note: Descriptions are shown in the official language in which they were submitted.
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NOVET_, LEAVFNTNC'; 'V~TF'.M
This invention relates to novel leavening
compositions and to systems employing such
' compositions. More particularly, the invention
S relates to hemipotassium phosphate exhibiting
leavening action as the acid factor in baking
preparations.
BACKGROUND OF THE INVENTION
Various salts of the acids of
phosphoric acid, usually orthophosphoric acid or
pyrophosphoric acid are commonly employed as the acid
factor in combination with a carbonate factor in
leavening systems. Calcium, aluminum and sodium
salts, exhibiting different reaction profiles, find
use as leavening acids in different applications.
Sodium, aluminum and calcium salts have been widely
used as the acid factor in leavening systems.
The use of sodium acid pyrophosphate as an
acid factor in bakery leavening is known but an
undesirable flavor has been observed. Mixing a
calcium acid phosphate salt with sodium acid
pyrophosphate (SAPP) has been found to reduce or
eliminate the taste and also control the evolution of
gas after mixing the baking ingredients. In U. S.
1,834,747 to Stokes et al. there is described baking
powder formulas which contain the usual sodium
bicarbonate together with alkaline earth metal
phosphates such as monocalcium phosphate in admixture
with sodium acid pyrophosphate. It is reported that
the mixture results in a slowing of the evolution of
carbon dioxide as compared to sodium acid
pyrophosphate alone thereby allowing a more desirable
reaction profile. With variation in the amounts of
the various salts it is reported that the evolution of
gas during leavening can be controlled to provide
varied reaction profiles depending upon the
requirements.
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Baking powders contain as essential
ingredients an acid-reacting material and sodium
bicarbonate, with or without a filler. The acid-
reacting materials customarily used are alum and acid '
salts of phosphoric acid, pyrophosphoric acid, or
combinations of these materials. See U. S. Patents
2,630,372; 3,052,549; and 3,501,314.
SL~A_T2Y OF THE TNVF'.NTTC~N
In accordance with this invention there is
provided hemipotassium phosphate leavening agent
provided by combining mono potassium orthophosphate
with phosphoric acid in equal molar amounts and heated
to a temperature above 100°C. The hot mixture is then
placed in a vessel and agitated vigorously whereby the
free water is removed as the mixture crystallizes.
Potassium hemiphosphate crystallizes driving off any
free water to produce a granular, free flowing, fast
dissolving, dry material having less than about 0.30
free water. Hemipotassium phosphate in the form
produced by the process of this invention is highly
useful as a leavening agent in conjunction with a
carbonate factor in the preparation of baked goods
such as pancakes, angel food cake as well as other
bakery goods requiring leaving.
BRIEF DESCRIPTION nF THE DRAWTNG
The attached drawing shows the result
of the DRR test employing a leavening system of this
invention at 27°C.
DETATLED DE~CRrpTTON OF THE INVENTION
In accordance with this invention a source
of potassium ion such as mono potassium phosphate is
combined with phosphoric acid to produce potassium
hemiphosphate. The reaction may be represented as
follows:
KHzP04 + H3P04 > KH~ ( P04 ) a
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The hemipotassiumphosphate can be initially prepared
' by combining a potassium source other than the
orthophosphate salt such as the hydroxide or other
' suitable potassium base. The convenience in providing
the potassium by means of the orthophosphate salt is
the reduction in the amount of free water introduced
into the mixture. It has been found that the most
efficient process employs the least amount of free
water. There is usually free water present in the
initial mixture from the phosphoric acid, which is
typically only 850, the remaining weight being water.
The hemiphosphate is heated by any typical
means such as a jacketed vessel or oven to a
temperature in the range of from about 100C to about
195C. Higher temperatures may be employed, however,
the hemiphosphate becomes highly corrosive at higher
temperatures making the process expensive and
cumbersome. Usually, the initial mixture typically of
mono potassium orthophosphate and phosphoric acid is
heated to a temperature in the range of from about
105C to about 120C. The mixture is usually heated
for a period of from 1.5 to about 2 hours. After
undergoing the heating step, the hemiphosphate still
contains free water and is relatively fluid.
The hot liquid is then placed into a
suitable mixing device which is capable of providing
vigorous agitation and also preferably containing
cooling means. As the liquid cools, crystals of
potassium hemiphosphate form, first at the sides of
the vessel and then throughout the mixture. Continued
agitation and cooling provides an increasingly viscous
slurry of crystals and with continuous, vigorous
stirring the entire contents of the vessel becomes
crystalline, driving off substantially all of the free
water. As the contents of the mixing vessel cools to
a range of from about 25C to about 40C the material
becomes a free flowing powder. Tmmediately after
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cooling and crystallization, the powder can be placed
in containers and shipped as substantially dry powder.
It has been found that the process of this invention
provides crystallized hemipotassium phosphate having
less than 0.3% free water, by weight. Surprisingly,
the free water contained in the initial mixture, after
heating, is removed at ambient room conditions t25°C,
standard pressure) during the crystallization step
without special devices or removal steps. Thus,
although the crystallized potassium hemiphosphate is
found to contain very little free water, no special
devices or process steps are required to achieve this
result.
The potassium hemiphosphate of this
invention has been found to be somewhat hygroscopic at
higher temperatures during extended exposure to humid
air. For example, after 24 hrs. of exposure at 30°C
and 74.9% relative humidity, weight gain was in the
range of from 2.5% to 2.8% while exposure extending
for 70 hrs. provided a weight gain of from 10.6% to
11.6%.
The dried, sized hemipotassium phosphate of
this invention are employed as the acid factor in
leavening systems in t~rpical application with a
carbonate factor. Carbonate factors include any
suitable basic materials such as sodium bicarbonate as
well as other basic materials such as potassium
bicarbonate, amorphous calcium carbonate, ammonium
bicarbonate, or encapsulated bicarbonate and the like.
It has been found that approximately 140 ,
parts, by weight, of the hemipotassium phosphate of
this invention is employed to neutralize 100 parts, by
weight, sodium bicarbonate. Appropriate amounts of
the hemipotassium phosphate useful in various
leavening systems are easily calculated in view of the
above. Other amounts may be employed to provide
particular desired finished product characteristics.
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Suitable weight ratios of the leavening acid of this
' invention to several carbonate factors is in the range
of from about 0.91 to about 1.49 preferably from about
' 1.18 to about 1.49 for most baked goods.
There is provided chemical leavening systems
for baked goods in accordance with this invention by
combining leavening acid of this invention as the acid
factor with a suitable carbonate factor. Carbonate
factors useful in accordance with this invention are
20 those previously known.
The hemipotassium phosphate of this
invention can be employed in admixture with other
previously known leavening acids which include,
without limitation, monosodium dihydrogen phosphate;
dimagnesium phosphate; sodium aluminum phosphate
acidic; a mixture of sodium aluminum phosphate acidic
with aluminum sulphate anhydrous; a mixture of sodium
aluminum phosphate acidic with anhydrous coated
monocalcium phosphate; monocalcium phosphate;
dicalcium phosphate dihydrate, anhydrous monocalcium
phosphate, coated; monoammonium phosphate; diammonium
phosphate; sodium acid pyrophosphate; monosodium
phosphate and sodium acid pyrophosphate blends; citric
acid; adipic acid; mixtures of monocalcium phosphate
and sodium acid pyrophosphate; mixtures of sodium
aluminum sulphate and monocalcium phosphate;
monocalcium phosphate, anhydrous; fumaric acid;
monocalcium phosphate and sodium aluminum phosphate
mixtures; glucono-0-lactone; monopotassium tartrate;
sodium aluminum sulfate; aluminum sulfate and any
a
other suitable, edible, non-toxic acid. Further,
coated or encapsulated acids are useful. Typical
a
coatings known in the art are fats, maltodextrin, etc.
The chemical leavening system of this
invention may be incorporated into a baking powder
product conveniently prepared by admixing leavening
acid of this invention with a carbonate factor as a
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dry powder mix alone or in combination with other
acidulants (for example, SAPP and sodium aluminum
sulfate). It is well known that baking powders in the
dry powder form are best prepared together with
fillers contributing to the bulk of the powder and
aiding its measurement for actual use. Fillers such as
starch or calcium carbonate are generally employed in
baking powders of this invention. Conventional
preservatives and fillers may be employed together
with the baking powder composition of this invention
as is known in the art.
Fresh dough, dry mixes and batter can be
prepared from the leavening systems of this invention
in the conventional manner as has been practiced in
the art. Typically the ingredients may be dry mixed or
prepared as a dough or batter. The dough or batter
may be stored for conventional time periods (under
refrigeration or frozen). The dry mix is employed to
prepare fresh dough or batter by incorporating
suitable liquids such as milk, water, eggs and solids
such as shortening materials as is known in the art.
It is obvious from the above that substitution or
replacement of conventional sodium salts with the
hemipotassium phosphate of this invention will reduce
the amount of dietary sodium and fortify with
potassium.
As is known in the art, the desired pH of
the final baked goad can be controlled by incorporat-
ing into fresh dough or batter leavening acids and
alkaline carbonate sources normally employed for that
purpose in the art. Generally, the pH of the final
baked product ranges from about 5.5 to about 8.5,
preferably from about 6.9 to about 7.2 (product
dependent). The amount of alkaline carbonate material
added should provide sufficient carbon dioxide.
Typically there is included from about 0.3% by weight
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to about 3~ by weight of the edible, alkaline agent,
based upon the weight of the dry ingredients employed.
The typical uses and levels of leavening
' acid of this invention typically employed therein are
provided in the table below. The listed baked goods
are representative only and not intended to limit the
invention in any way as other uses and baked goods can
be made from the leavening system of this invention.
The level of acid used with common, commercially
available carbonate factors is an amount sufficient to
neutralize and liberate carbon dioxide. The
percentages shown are for the amount of hemipotassium
phosphate of this invention as percent of solids to
neutralize sodium bicarbonate.
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PRODUCT WT. PERCENT
Self-Rising Flour-Like Product* 0.2 - 1.1
Self-Rising Corn Meal-Like Product*0.2 - 1.5
Biscuit Mixes 0.2 - 1.4
Breading/Batter Mixes 0.0 - 1.4
Cake Mixes - Layer 0.08 - 0.7
Cake Mixes - Angel 0.2 - 1.4
Cake Doughnut Mixes 0.07 - 0.7
Cookie Mixes 0.0 - 0.5
Hush Puppy Mixes 0.2 - 1.4
Frozen Pancake Batter 0.08 - 1.7
Pizza Mixes 0.04 - 0.9
Refrigerated Doughs 0.2 - 1.8
Pancake Mixes 0.2 - 1.5
Frozen Biscuit Doughs 0.2 - 0.7
Muffins 0.2 - 1.5
Baking Powders 2.9 - 30
Crackers 0.07 - 1.3
Waffle Mixes 0.2 - 1.5
Frozen Cake Batter o.08 - 0.5
*Hemipotassium phosphate is not currently listed in
the standard of identity for Self-Rising Corn Meal and
Flour.
The moisture content of the fresh doughs and
6
batters of the present invention generally range from
about 5% by weight to about 130% byAweight, based upon
the weight of the dry ingredients. The moisture
content will vary, dependent upon the ultimate utility
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of the dough or batter as to whether it may be
employed to prepare cookies, biscuits, cakes, etc.
Baking times of the fresh doughs or batter
of this invention are generally within the baking
times generally known in the art with respect to the
use of previously known leavening systems. It is
typical that various mixes of fresh dough or batter
will require different baking times considering as
well the baking characteristics of the ovens employed.
Typical baking times range from 7 to 15 minutes for
cookies and longer periods for biscuits and other
baked goods. The doughs or batters of the present
invention are formed into pieces ar deposited in
conventional manner, using known bakery equipment such
as wire cutting devices, rotary cutters, reciprocating
cutters, and the like.
Typically, fresh dough and batter are
prepared as in the prior art from flour, shortening,
sugar, optionally emulsifiers and preservatives and
from about 0.04% by weight to about 2.0~ by weight of
the leavening acid of this invention and appropriate
levels of a carbonate source. Other optional
ingredients, of course, can be included as is well
known in the art.
The fresh doughs and batters of the present
invention can optionally include many substances known
in the art to be added to fresh dough and batter
including bulking agents such as dietary fiber and
hydrocolloides, corn fiber, soy filtrate, wheat bran,
and apple tomace fiber (dehydrated and freeze dried)
as exemplary of dietary fibers.
c
Texturizing and flavoring ingredients
conventionally used in the production of baked goods
may be employed in the novel doughs of this invention.
The amounts employed are generally comparable to those
used in the conventional formulation so as to achieve
satisfactory mouthfeel, texture and taste. Typical
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amounts of conventional texturizing and flavoring
ingredients used in the production of baked goods are
in the range of from about 5% by weight up to about
25% by weight of the fresh dough or batter. Other
additives such as sweeteners, etc. can also be
employed in combination with the novel leavening
system of this invention.
The following non-limiting examples
illustrate the preparation of compositions useful in
the process of this invention. In these examples
percent is expressed as percent by weight unless
otherwise noted.
''HE PREFEI
EXAMPLE 1
Into a suitable container were placed 581 g
of mono potassium phosphate and 493 g of concentrated
phosphoric acid (85%). The mixture was agitated by
means of a power mixer for a period of 5-10 minutes
resulting in a viscous liquid. The liquid was then
placed in an oven heated to a temperature in the range
of 190°C to about 200°C. After heating the liquid in
the oven for a time in the range of from 1.5 to 2
hrs., the temperature of the liquid reached 120°C at
which temperature it was removed from the oven. The
liquid was again subjected to vigorous agitation by
means of a power mixer whereupon crystals.formed as
the liquid cooled by air convection. No external
cooling was applied. Crystals continued to form
during cooling and when reaching a temperature in the
range of from about 25°C to about 40°C the material ,
became a free flowing powder.
The powder was analyzed (ASTM D-2761) and
found to have the following analysis as percent by
weight:
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Trimetaphosphate 0.10
Tripolyphosphate 0.08
Pyrophosphate 2_20
Potassium Orthophosphate 97.62
Recovery 99.21
P205 6 0 . 6 7
An aqueous solution (1°s) of the above
described composition indicated a pH of 2.24 and loss
on drying at 110°C was 0.070
RXAMPT,R 2
The hemipotassium phosphate of this
invention was tested as the acid factor in a leavening
system of a pancake batter. A pancake batter was
prepared as follows:
To a bowl was added about 180 g of Roland
Pancake Base Mix. Separately, 3.94 g of
sodium bicarbonate and an amount of
leavening agent shown below in Table I were
placed into a tared boat. The mixture of
leavening acid and soda were sprinkled over
the mix and incorporated with a whisk. Then
197.6 g of water were added to the mix and
blended with a whisk.
The leavening acid employed in each sample
tested is listed below:
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TABLE I
a
Sample Leavening Acid NeutralizingGrams
No. Value
1 Hemipotassium 140 2.79
Phosphate
2 Citric Acid 153 2.57
3 Hemipotassium Phosphate140 2.81
4 Hemipotassium Phosphate105 3.75
5 Citric Acid 131 3.01
In the pancake bake test a level #24 scoop
of batter was employed to make pancakes for the tests
reported in Table II below. The batter was poured
onto a heated griddle maintained at 375°F making eight
pancakes. The pancakes were baked for 1.5 minutes and
then turned over and baked fox an additional 1.5
minutes. After baking they were removed from the
griddle and evaluated.
The texture of the pancakes is reported in
Table II below. To determine texture, a stack of 3
pancakes were subjected to a probe traveling at 1.5
mm/sec. under a weight of 2I2 g. The distance the
probe became embedded into the stack of pancakes under
said weight was measured in millimeters (Texture).
Texture, in turn, is related to tenderness of the
baked good which is an indication of the amount of
leavening. The greater the texture number, the
greater the tenderness. A texture of at least 9.0 mm,
preferably at least 10.0 mm, is considered
satisfactory leavening. The above mentioned test
results and data appear in Table II below wherein
texture is reported in mm.
A sample of the pancake batter was also
taken to test volume increase without heating. Into a
100 ml graduated cylinder was added about 50 ml of the
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batter. The volume in the cylinder was noted after 30
' minutes to determine whether there was any expansion.
The observed initial volume in the graduated cylinder
is subtracted from the volume observed at 30 minutes.
The difference is divided by the initial volume to
determine the percentage of expansion at 30 minutes.
The percentage expansion in the graduated cylinder is
also shown in Table II below.
The specific volume of the pancakes was
l0 determined by dividing the weight by the volume.
Also, the "spread" of the pancake was determined by
dividing the diameter by the height of the pancake.
TABLE II
Sample ExpansionSpread Texture Sp. Vol. pH
No.
1 20 10.89 14.2 2.16 7.0
2 - 9.96 9.18 1.98 6.9
3 - 7.92 13.12 1.66 7.4
4 - 12.91 1.73 6.9
5 - 8.23 2.29 6.7
EXAMPLE 3
The product of Example 1 was employed as the
acid factor in a leavening system of an angel food
cake mix. To this mix was added sodium bicarbonate,
Grade 2, the product of Example I, and monocalcium
phosphate. To this dry mix was added water and the
mixture was blended to a uniform consistency. After
scraping down the sides and bottom, the batter was
mixed for an additional minute at the same speed.
Samples were taken for determination of specific
gravity and volume increase without heating, then
235.8g of batter were deposited in 10 cupcake forms of
a prepared pan with liner. A graduated cylinder was
filled to 72mm at room temperature and after 30
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minutes an expansion of 4.25 was observed. The
cupcakes were baked for 33 minutes in an oven at
350Y~'. The baked cupcakes were then taken from the
i
oven and allowed to cool before evaluation. Specific
gravity of the batter was determined to be .4947g/cc.
The specific volume of the cupcake (rapeseed) was
3.57cc/g. To determine texture, a single cupcake was
subjected to a probe traveling at 1.5 mm/sec under a
weight of 212 g. The distance the probe became
embedded into the center of the cupcake under said
weight was measured in millimeters. Texture was 10.58
mm at the center of the cupcake. The pH of the cake
was found to be 7Ø The crust was golden brown with
nice cracks with air cell openings and good bounce.
The crumb exhibited fine cell structure with medium
cell walls. The taste was sweet and typical of angel
food cake.
L'VTA~77T L~ A
The procedure of Example 3 was repeated with
the exception that 1.26g of citric acid (N.V. 153) was
employed in place of hemipotassium phosphate.
evaluation. Average weight of IO cup cakes was
23.11g. Specific gravity of the batter was determined
to be .4469g/cc. The.specific volume of the cupcake
(rapeseed) was 3.55cc/g. To determine texture, a
single cupcake was subjected to a probe traveling at
1.5 mm/sec under a weight of 212 g. The distance the
probe became embedded into the center of the cupcake
under said weight was measured in millimeters.
Texture was 12.83 mm at the center of the cupcake. .
The crust was light golden brown with some cracks and
with air cell openings and good bounce. The crumb i
exhibited medium cell structure with medium cell
walls. The taste was sweet and typical of angel food
cake with a slightly more tender bite than in
Example 3.
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Although the invention has been described in
terms of specific embodiments which are set forth in
considerable detail, it should be understood that this
description is by way of illustration only and that
the invention is not necessarily limited thereto since
alternative embodiments and operating techniques will
become apparent to those skilled in the art in view of
the disclosure. Accordingly, modifications are
contemplated which can be made without departing from
the spirit of the described invention.
