Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
104~337
Background of the Invention
The present invention relates to a dried proteln
product of lmproved emulsiflcation properties and flavor.
Isolated protein which is derived from vegetable
protein sources such as soybean meal has been determined to
possess a wide degree of functlonallty in various food products.
One application for this material has been in the preparation
Or ground meat products. The isola~ted soy protein or ~lour
has been used in these ground meat products as a fat emulsifier
and water binding agent. Normally, however, the relative
percentages o~ ~at and molsture ls so hlgh in ground meat
products that a hlgh percentage Or protein material must be ~;
used to ~orm a stable emulsion with the ~at and water. By the
same token, the use of a higher percentage o~ soybean flour
lmparts an undesirable flavor to the meat product because
Or the "beany" ~lavor that ls characteristic of soybeans. For
thls reason, sodlum caseinate or proteln sources derived ~rom
materials other than soybeans have been employed to overcome
the ~lavor problem assoclated with soybean blnders ln ground
meat products. However, while the flavor problem ls overcome,
casein ls relatively ine~fective in providing a stable emulsion.
This is readily illustrated by a cooking test in which an emul-
slon Or ~at, water and protein is ~ormed, after which it is
oanned and retorted at 245F. under pressure to coagulate the
proteln. The emulsion can be removed as an integral mass,
a~ter which lt is cooked in a hot skillet and the ~at and
molsture loss measured. Usually, emulsions prepared with
sodium caselnate as a blnder wlll completely melt or dislnte-
grate upon cooking.
United States Patent 2,881,076 descrlbes a soy protein
composition and method for its production includin~ its use as
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- . ~. .
37
an emulslfler for fat and water. This protein composition, of
desirable emulsification properties is produced by heating
the aqueous mass of protein at a pH above 6 at a temperature of
100 to 180F. to render the protein more colloidal or gel-like.
The solids suspension, after heat treatment is then dried to
rorm a ~owder useful as a binder for ground meat. While the
emulsification properties of the soy protein is enhanced by
thls treatment, nevertheless protein products produced by this
process still suffer from the above descrlbed deficlency with
regard to flavor.
The flavor of isolated protein derived from soybeans
has been significantly improved by processing techniques such
as described in United States Patent 3,642,490. The process
descrlbed in this patent relates to controlled dynamic heating
o~ an aqueous slurry of the soy protein to an elevated temper-
ature range followed by physlcal working of the slurry under
dynamic condltions and under controlled posltive pressure. The
slurry i5 retained for a brief period of time under these con-
dltions after which the undesirable flavors are removed by
causing subsequent lnstant pressure release to cause flash off,
wlth vaporizatlon of some of the moisture that is laden with
these undeslrable flavor components. The slurry ls then dried
to a white powder of a substantlally bland flavor. Whlle the
product is markedly improved in flavor, nevertheless, lt ls
not as deslrable as a binder for ground meat products. Further
processlng ls requlred to produce a product suitable as
emulsifier for fat and water mlxtures which is of the same
quallty o~ blandness as this product but which has superior
emulsifying properties.
It ls therefore an ob~ect o~ the instant invention
to produce a soybean protein product with a bland flavor having
improved emulsification properties.
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337
It is also an object of the instant invention to provide
a process for the production of a protein isolate which signific-
antly enhances its emulsifying properties while retaining a
substantially bland flavour.
It is a further object of the instant invention to
provide a process for the production of such a product that
is economical and commercially feasible to produce.
It is another object to provide a protein product
that will effectively bind fat and water emulsion even when
the emulsion is subjected to cooking.
Summary of the Invention
The emulsification properties of a dried soy protein
isolate having improved flavor characteristics has been markedly
improved by the addition of an edible reducing agent to the
aqueous protein slurry either before or subsequent to the dynamic
heating step together with critical control of the drying temp-
erature of the isolate to below about 200F. The instant process
for the production of a soy protein isolate having these propert-
ies therefor includes, in one aspect, the process for the prod-
uction of a dried protein isolate of improved emulsificationproperties and flavor comprising: forming a slurry of isolated
90y protein having a ph of about 5.7 to 7.5, dynamically heating
said slurry under a positive pressure at a temperature above about
175F, retaining the heated slurry under a positive pressure for
at least a few seconds, releasing the pressure to cause flash off
volatilization and removal of moisture laden with undesirable
flavor components, adding to the slurry an edible reducing agent
in an amount of at least about 0.1% by weight of the solids in
the slurry to improve the emulsification properties of the soy
protein, and drying the slurry at a temperature below about
200F. to produce a dried protein isolate. AlthoUgh in the
previous production the edible reducing agent is added subsequent
to the heating step, it may be added prior to the heatlng step
~ - 4 -
~'
~ 04a"~37
to also alter the properties of the protein isolate
and as a consequence improve its emulsification properties.
Althouyh not limiting, it is theorized that an en-
hancement in emulsification properties of the isolate
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~t
~ 04~;;337
is achi~ved by a change in the svlubility characterlstlcs
Or the isolate because of the processing techniques. This
results in the productlon Or an lsolate that is a better
emulsirler because Or the colloidal nature Or the dried protein
particles. This change in the physlcal characteristics Or the
particl s ls belleved to be due to the effect Or the reduclng
agent and drying temperature on the rate of hydration
Or the drled soy protein. The edl~le reduclng agent can be
added to the slurry immediately prior to the dynamic heating
step or subsequent to it. Following deflavorization, a drled
protein isolate is produced by drying of the protein slurry.
It has been determined that lr critlcal control Or the drylng
temperature ls maintained together with the addition of a reducing
agent~ the emulsiflcation propertles Or the dr~cd product are
further lmproved. In thls regard, lt has becn detcrnlincd that
it ls necessary to control the drying temperature to below about
200F. and preferably between 165 and 200F. When the temperature
ls permitted to exceed 200F., the rate of hydration Or the
dried proteln product and hence its emulslrlcation properties
are less deslrable.
It has also been determined in con~unctlon with the
sbove that the addition Or an edible reducing agent is necessary
to achieve an improvement in emulsificatlon properties Or the
protein, wlth the amount Or addltion belng at least about 0.1%
by weight Or the solids, with a prererred range of 0.1 to 2.0
by weight of the solids. The mlnimum percenta~e Or reducing
a~ent is necessary to change the emulsirication propcrties of
the protein while the upper limit is determined slmply by the
need to avoid another flavor problem, this one associated with
a hlgh level Or reducin~ agent used to alter the physlcal
Gharacterlstlcs of the proteln.
E~
37
When emulsions of fat and water are prepared with the
protein isolate of the instant invention, canned and retorted
to coagulate the protein, the resultant products when fried
show less than 50Z Or the fat 105S which characterizes the same
product without the addition of reducing agent. The
isolate, however, st~ll possess~s the highly desirable
bland flavor characteristics of the isolate which has
employed a dynamic heating step to~deflavorize the pro-
telnaceous slurry.
Description of the Preferred Embodiments
In a brief outline Or the total process, the soy-
beans forming the starting material are ground or crushed,
the oil extracted to leave soybean meal or flakes, the pro-
telns and sugars are dissolved out of the flakes into solution,
the proteins are precipitated, washed and put into water sus-
pension as a slurry. The slurry is ad~usted to a controlled
pH range as described in detail hereinafter. The slurry also
has a controlled range of solids. The slurry is thereafter
deflavorized by a dynamic heating step employing positive
pressure and "flash off" or release of pressure to volatllize
entrapped flavors ln the protein. Prior to or subsequent to
deflavorization, an edible reduclng agent is added to the
slurry in a critically controlled amount to improve the emulsi-
ficatlon properties of the protein followed by drying of the
product at a temperature below about 200F.
More specifically, the soybeans are crushed or
ground in convenient fashion. The oil is preferably removed
by solvent extraction, using solvents normally employed for
this purpose.
The resulting sollds, commonly referred to as soy-
bean meal, and normally in the form of flakes, contain many
~04~37
lngred~ents including complex proteins, sugars, fibers, and
others. The proteins and sugars are then preferably dissolved
out Or the bath by adding a food grade al~aline mater~al to
ralse the pH to 7 or above. Typical of such alkaline reagents
i8 sodium hydroxide, potassium hydroxide, calcium hydroxide or
other commonly accepted food grade alkaline reagents. The
material is then extracted ror a period of time surficient to
put the proteins and sugars in solution, usually about 30 minutes
or so. The resulting liquor solution is separated ~rom the
solids, as by passing the material through a screen and/or
centrifuging. Preferably, the liquor is then cycled through
a claririer to remove tlny particles.
It may ~urther be desirable to include other chemical
reagents in the protein slurry during alkaline extraction
lncluded among which are the sulfite salts and these modlfications
o~ the alkaline extraction procedure are to be included within
the scope of the present invention. Insofar as the addition
Or sulrite ~ or similar reducing agent during extraction, most
Or this is removed during the protein isolation process so the
addition of the described percentage of reducing agent either
berore or after deflavorization is still necessary to improve
emulslfication of the protein, even if sulrite is added during
the alkaline extraction step.
The soy proteins are then precipitated from the liquor
by lowering the pH to an acidic value of the isoelectric point
Or the protein, usually a pH Or 4.6 - 4.9, with the addition
Or a common food grade acidic reagent such as acetic acid,
phosphoric acid, citric acid, or others. The preclpitate is
then separated as by centrlfuglng, and washed wlth water to
remove remaining sugars, except for a minute trace which is
practically impossible to remove. The aqueous slurry of the
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~ O~ ;37
preclpltated protein is diluted by adding water.
The slurry then has its pH ad~usted, specifically,
the pH ls ad~usted to a range of about 5.7 to 7.5, preferably
between about 6.5 and 7.2. Below about 5.7, the water
dlspersibility of the final product is very low and not useful
for many purposes. At a pH above about 7.5 and approaching 8.0,
the final product tends to assume an undesirable soapy taste.
The degree of disperslbillty in the flnal product can be regu-
lated by varylng the pH wlthln the controlled pH range of about
5.7 - 7.5, to sult the product to the final food being prepared.
The pH may be easily adJusted by adding a ~ood grade alkaline
reagent such as sodium bicarbonate, or an alkaline earth metal
hydroxlde.
The slurry to be further processed should have a
controlled solids content of about 3 - 30% by welght, and pre-
ferably about 5 - 17% by weight. If lt falls below about 3%,
subsequent processlng steps are not econom~cally advlsable when
a contlnuous process is employed. Drying is particularly costly.
Above about 17% sollds content, the resultlng product does not
subsequently lend itself to the preferred flash drylng tech-
niques, such as spray drying using a ~et or spinning thrower
or such, so that other drying techniques must be employed, to
result in a product that is not as desirable in its functional
¢haracteristics.
The aqueous slurry of soybean protein materlal may be
then sub~ected to dynamic heating pursuant to the deflavorization
procedure as hereinafter described, after which reducing agent
additlon can be carried out, or alternatively the reducing agent
can be added be~ore the de~lavorizatlon procedure. In either
situation the reducing agent is added in an amount of at least
about 0.1% based on the weight of solids in the slurry, with a
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~ 04~;337
preferred level of addition being between 0.1 and 2.0% by weight
Or solids.
The edible reducing agent may be selected from a
varlety Or materials including sulfur dioxide, sulrurous acid
or salts thereof such as the sulfites and bisulfites, or salts
Or phos~horous acid such as the phosphites. Typlcal salts of
choice include the alkaline earth salts such as sodium and
potassium. The present invention is not intended to be limited
by the particular type Or edible reducing agent that may be
employed, provided that the source is capable Or ionization in
an aqueous system to yield a reducing component to improve the
rate of hydratlon of the protein.
The de~lavorizatlon process Or the present invention
ls that disclosed in United States Patent 3,642,490 which
comprises sub~ecting the aqueous slurry to dynamic heating under
positive pressure, followed by "flash off" or volatilization of a
portlon o~ the moisture by e~ection of the pressurlzed slurry
lnto a vacuum chamber or area Or negative pressure. In this
manner entrapped flavor components are readily removed. The
positive pressure can be created in the aqueous suspension
ltself by direct steam in~ection into the slurry and conrinement
Or the slurry, or the slurry can simply be conrined and the
temperature elevated without direct steam in~ection.
The application Or positlve pressure, sub~ects the
slurry to dynamic working while at this elevated temperature
range. Currently, a typical but nonlimiting apparatus used
to achieve this is a de~ice known as a ~et Cooker. It includes
ad~acent ~et nozzle orifices, normally concentric, through
which the slurry and the pressurized steam used as a heating
agent are e~ected at high veloclties in intersecting flow
patterns, so that each tiny bit of slurry ls instantly dynamlcally
3j~37
heated by the steam while practically simultaneously being
sub~ected to severe physical forces at the nozzle, such physical
workln~ being largely of a shearing nature. The physical working
of each tlny portion is believed to expose the obnoxious sub-
stances to further action, and this physical working with the
elevateæ temperature heat treatment is believed to weaken and/or
break the tenacious bond between these obvious substances and
the complex protein molecules, to an extent where these
substances can be laded away by flashed orf vapors, as described
hereinafter. Thls physical working and heating also tends to
eliminate some Or the characteristic soy flavor, but more
importantly, prepares the material for the subsequent processing
steps. The temperature range to which the slurry is heated for
the desired results is about 175 - 400F., although the tempera-
ture should not be in the lower region of this range unless the
product is subsequently vented into a vacuum chamber after
being held under pressure in a special holding chamber, as
explained herelnafter. Normally,the temperature should be
about 285 - 320F. for best results.
The product is introduced to the Jet Cooker nozzle
at a positlve pressure. Thls pre~.sure should be at a value
near the pressure Or the steam in~ected into the slurry,
should be sufficient to cause high-velocity discharge of the
slurry through the ~et nozzle, and must be greater than the
pressure in the special retention chamber lmmediately down-
stream of the nozzle. Normally the steam pressure is about
80 - 8~ psig, the slurry line pressure is slightly above the
steam pressure, usually about 85 - 100 pslg, and the dlscharge
pressure ln the chamber downstream of the nozzle is about
6;5 - 80 pslg. The pressure drop of the slurry across the nozzle
is about 5 - 15 psi, depending upon these other pressures, with
6 - 10 psi being common.
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~04s~37
The time interval of thc slurry in the nozæle is
estimated to be about 1 second or less. The nozzle ori~ice
for the slurry is small, being only a fraction of an inch, e.g.,
about one-eighth lnch, so that t~le slurry sollds are sub~ected
to severe dynamlc, physlcal working during passage. The steam
intermi~es intimately wlth the solids in the e~ected slurry.
The amount of steam requlred is not great, normally being an
amount to lower the solids content ~o~ the slurry about 1 - ~%
by weight. Preferably the nozzle orifices are concentric, with
the slurry being eJected from the center orifice, for example,
and the steam from a surrounding annular orifice oriented to
cause its output ~low path to intersect the output flow path
of the center orlfice. The slurry and steam could be e~ected
rrom the alternate orifices however. Further, the ad~acent
orifices need not necessarily be concentrlc to obtaln this
interaction.
As noted prevlously, the steam and slurry are e~ected
lnto a special retention chamber. This may comprise an elongated
tube through which the lntermixed slurry and steam moves from
the ~et nozzle on one end of the tube to a pressure controlled
dlscharge on the other end. The discharge can be controlled by
a conventional preset pressure release valve to enable con-
tinuou~ process flow ~rom the nozzle to and o~t o~ the dlscharge
valve. mis valve regulates the pressure in the holdlng chamber.
Thls chamber pressure must be great enough to prevent any slgni-
~lcant vaporlzation Or the moisture in the chamber, even though
the temperature is well above the boillng point of water. A
pressure of about 65 - 80 psig readily achleves this. Slnce
slurry and steam must continuously ~low into this pressurized
chamber, the pressure behind the slurry and the steam must be
greater than the chamber pressure to cause this continuous flow.
~O~i~;337
The heated slurry ls retained in the holding ch~mber
for a definite but relatively short period of a few seconds
up to a ~ew minutes, normally Or about 7 seconds to about
100 seconds and preferably from about 3 to 20 seconds. It is
only necessary to retain the product in this heated condition
for a f~w seconds for optimum reiults. Therefore, the pa ticu-
lar retention time is not deemed to be limlting insofar as
the present invention.
The pressure on the slurry is then instantly released
by dlscharging the slurry to a reduced pressure zone, into a
suitable receiving means. This causes "flash off" of a portion
of the moisture in the form of water vapor which is laden with
the entrained odiferous chemical components or substances of
unknown composition from the soy product. The flash off also
causes substantial coollng of the remalning slurry because
Or the heat o~ vaporlzation absorbed from the slurry, so that
the total time which the product is sub~ected to elevated tem-
peratures is very short and controlled. Removal of the substance-
laden vapors removes the ob~ectionable ~lavor and odor components.
The reduced pressure zone into which the slurry is
dlscharged is normally at atmospheric pressure, but it is
sometimes subatmospheric, i.e. at a partial vacuum. In elther
case, the vapors should be lnstantly conducted away from the
slurry, preferably by a movlng current of air across the slurry
or by drawing a continuous vacuum on the discharge zone to draw
the vapors away. The vapors may be specially condensed in a
fashion to positively remove the condensate from the area of
the collected discharged slurry. In production, the slurry
may be discharged from the back pressure control discharge
valve directly into a vessel ln the open atmosphere where the
vapors are allowed and/or caused to rise directly away from the
,
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~ 04~;337
slurry and are prevented rrom condensing in a manner to a:low
the condensed substance to flow back into the product.
To assure complete removal of the vapors from the
purifled slurry wlthout allowlng the vapors to recondense back
lnto the slurry, the slurry and vapor should be separated
immediately after dlscharge, l.e. lmmediately after pressure
release. In thls regard lt ls ur.deslrable to cause passage
of both components through a common conduit downstream of the
discharge valve, and lf such is done, lt should be minlmal.
The aqueous slurry may then be dried to a powdery
condltlon, and lt ls preferred to flash dry the product because
of the unlform nature of the product obtalned. It has further
been determined pursuant to the instant invention, that lf the
drying temperature of the protein product is controlled to below
about 200F. or preferably to between about 165 to 200F. that
the emulsification properties of the dried protein material are
further im~roved. It is theorized that this is due to the
better hydration capacity of a proteln product dried at this
temperature slnce when a temperature above about 200F. is used,
the dried protein material does not hydrate as readlly. Of
the flash drying techniques, spray drying is usually employed.
The lnstant invention is not intended to be limited by the
particular drying technique employed and other techniques may
be employed provided that the temperature is controlled as
stated. The dried protein product is then suitable as an
emulsl~ier fox water and fat systems as are ordinarlly found
in ground meat emulslons or products such as sausage, frank-
furters, etc. In determinlng the suitablllty o~ the lnstant
product as an emulsl~ler for ground meat products it is common
to employ the protein product in a test for emulsification
properties as hereinafter described.
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The protein product is combined with fat and water in
respective weight ratios of 1 part protein to between about
3 to 9 parts of both fat and water. Typically, a weight ratio
of 1 part proteln, 5 parts fat and 5 parts water is employed.
Thls mlxture is then homogenized to form an emulsion and placed
ln a suitable container such as a can. The product is then
cooked for between about 15 to 20 minutes at 230 to 250F. to
coagulate the protein and form a substantially unsegregated
mass of the emulsion. A portion of the emulsion is then taken
and placed ln a frying pan and fried, after which the loss of
water, and particularly fat due to cooking is measured. In
this manner, the emulsification properties of the protein
product may be evaluated, in that the loss of fat is directly
associated with the emulsification propertles of the protein
product. It is desirable of course to keep the loss of fat
due to cooklng to a minimum.
The followlng Examples are set forth as speclflc
embodlments Of the lnstant invention for illustratlve purposes.
Example 1
? About 500 lbs. of solvent extracted soybean flakes
were suspended in 5000 lbs. of water to which was added 1.8%
Or calcium hydroxide thereby raising the pH to about 10.5.
Additionally, 1.5% of sodium sulfite was added to the alkaline
slurry. The mixture was held at 90F. and extracted for
30 mlnutes. Following extractlon, the undissolved solids and
spent ~lakes were removed by centrifugation and resuspended
in 600 lbs. of water. The resuspended mixture was again
centrifuged and the spent flakes discarded. The original
extract and that of the resuspended flakes were combined. The
pH of the extract was lowered to about 4.5 wi~h phosphorlc acid
to precipitate the protein. The water was removed from the
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337
precipitated protein by centrifugation and to the "curd" was
added an equal volume of water for washing of it. After agita-
tion, the water wash was removed by centri~ugation, thereby
ylelding 615 lbs. of curd at 27.9% solids.
The 615 lbs. of curd was dispersed in 640 lbs. of
water tc produce a solids level of 13.6% by weight, and the pH
of the slurry was ad~usted to 6.8. One hundred pounds of the
slurry was then passed through a Jet Cooker. The steam heats
the slurry through the Jet Cooker to a temperature of 310F.
The heated mixture is held under a posltive pressure for 10
seconds, after which it is discharged into a vacuum chamber held
at a pressure of 20 inches of mercury. This causes flash
off volatilization of moisture laden with undesirable flavors.
To a 50 lb. portion of the ~et cooked slurry was added 0.2%
sodium sulfite based on the weight of the sollds ln the slurry.
Thls sample was spray dried at a temperature of 18~F. to yield
a desirable, whitlsh protein powder of a bland flavor.
Example 2
To a second 50 lb. portion of the ~et cooked slurry
produced in Example 1 was added 0.4% sodium sulfite based on
the weight Or solids in the slurry. This sample was spray
dried at a temperature of 180F. to yield a whitish protein
powder of a bland flavor.
xample 3
To a 75 lb. portion of the aqueous slurry prior to ~et
cooking, as set forth in Example 1, having a pH of 6.8 and a
solids content o~ 13.6%, was added 0.2% by weight of sodium
sul~ite, based on the weight of solids in the slurry. The slurry,
with added sulfite is then passed through a Jet Cooker, and the
Jet Cooker ~s used to heat the slurry to a temperature of 310F.
The heated mixture is held under a positive pressure at this
~(J4~37
temperatlre for 10 seconds after which it is discharged lnto a
vacuum chamber held at a pressure of 20 in. of mercury, at which
time flash off volatilization of the flavor components takes
place. The cooked slurry was then spray dried at 180F. to
yield a whitish prote~n powder of a bland flavor.
Example 4
The spray dried protein products obtained from
Examples 1, 2 and 3 were then comparatively tested against
a spray dried quantity of ~et cooked product designated as
the control which had been processed pursuant to Example 1
absent any addition of sulflte. The testing was designed to
evaluate the relative emulsification properties of these
protein products and were handled as follows:
Protein, fat and water emulsions were prepared by
adding 150 grams of the proteln products from Examples 1 to 3,
and the control of 500 ml. of water ln a food chopper and
chopplng the mixture for 90 seconds. Three hundred fifty grams
of pork fat back was then added, and the mixture was chopped
for an addltional 3 1/2 minutes.
The four dlfferent emulsions were then placed in 7 oz.
cans and retorted at 250F. for 30 minutes. Following retorting,
each emulsion was removed from the can, at which tlme it was
observed that the emulsions produced pursuant to Examples 1 to
3 were excellent in quality with little visible separation of
fat and water while the control showed a considerable separation
of the fat.
At this time, each solidified emulsion was sliced in
half, and each half portion from each emulsion having the
following designated we~ght was separately placed in an
electric skillet held at a temperature of 340F. and cooked on
one side only for 10 minutes to determine fat and moisture loss
- 16 -
~04~;~3~7
on cooking for each portion. The results of this testing are
set forth below in Table 1.
Table 1
Cooking (gm) Average
% Weight Weight % %
SampleSulfite Before A~terCookout Cookout
Example 1 0.2 89.3 85.2 4.6 4.7
84.3 80.3 4.7
Example 2 0.4 79.4 76.2 4.0 4.1
86.6 83.o 4.2
Example 3 0.2 72.0 70.0 2.8 3.1
85.2 82.3 3.4
Example 4 0 74.1 67.6 8.8 8.3
91.0 84.o 7.7
It may be seen from the data in Table 1 that the samples of
proteln product pursuant to Examples 1 to 3 was significantly
better than the control in emulsifying the mixture of fat and
water, as evidenced by smaller cookout of the emulslons prepared
wlth proteln product produced pursuant to the lnstant lnventlon.
Example 5
A portion of washed curd produced as set forth
in Example 1 was ad~usted to a solids content of 13% by the
.addltion of water and the pH ad~usted to 6.6. To the slurry
was added 0. 3% sodium sulfite based on the sollds content and
the mixture was then passed through a ~et cooker. The steam
heated the slurry in the ~et cooker to a temperature of 310F.
The heated mixture was then retained under a positlve pressure
ror 10 seconds, after whlch lt ls discharged ~nto a vacuum
chamber to cause flash off volatillzation of undesirable flavors.
Followlng this, the mlxture was spray dried at 180F. to a
whitish powder.
~ This proteln product was then comparatively evaluated
agalnst the followlng products to determine its emulsiflcation
properties as compared to these products. Sample 1 was the
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~ (~4~37
protein product of thls Example, Sample 2 was sodium caseinate,
a prlor art emulsifier, Sample 3 was a soy protein 70%
concentrate, unprocessed to remove residual flavor components,
and Sample 4 was a protein product processed as described above to
remove resldual flavors, but without the addition of sulfite.
One part by weight of each of the above samples was
combined with 5 parts b~ weight of water, and 5 parts by
weight of pork fat back and chopped in a food chopper for 5
mlnutes to form an emulsion.
Each emulsion from each sample was then placed in
a 7 oz. can, sealed and retorted at 230F. for 30 minutes.
Following this, each emulsion was removed from the can and
sliced in half. Each half portion o~ each sample, was then
placed in an electric skillet held at a temperature of 340F.
and cooked on one side only for 10 minutes to measure fat and
moisture loss during cooking. The results of this test are
set rorth in Table 2.
Table 2
~ _ , .
~ooking ~gm~ Average
Weight Weight %
20Sample _ Before After Cookout Cookout
1 90.6 82.5 8.9 8.4
lol.l 93.2 7.8
2 87.2 Emulsion broke during cooking
85 .2
3 90.1 78.0 13.4 13.1
99.8 87.1 12.7
4 85.3 74.0 13.2 12.3
91.9 81.5 11.3
It may be seen from the above cooking data that the emulsion
using sodium caseinate as a binder could not withstand the
cooking test, ~nd the 70% soy protei~ concentrate had a much
30 higher cooking loss than the product of the lnstant inventlon.
- 18 - I
37
It is further illustrated by the above data, that a protein
product deflavorized as in the instant invention but wlthout the
addltlon of reducing agent had a higher cooklng loss than the
emulslon prepared with the protein product of the lnstant
lnventlon. The proteln emulslon contalning the product of the
instant invention was further ch~racterlzed by a very wh~te
color and essentially bland flavor.
The above Examples are merely illustrative of the
instant lnvention and lt will be understood that varlous other
changes in the details, materlals or steps whlch have been
descrlbed may be made wlthout departing from the spirlt of
the instant disclosure, and such changes or modl~ications are
intended to be included wlthln the scope of the lnstant
disclosure and appended clalms.
19
.
