Note: Descriptions are shown in the official language in which they were submitted.
:~468~)0
The present invention relates ta a process for treating
wheat flour and in particular such a process whereby gluten
and starch syrup products are obtained.
Backqround of Invention
Wheat flour comprises from about 70-85% starch, from
about 9-16% proteinaceous material ~about 12 to 21% gluten), and
a number of minor components such as hemicelluloses (pentosans)
and ash. The gluten and starch, and starch derived products,
especially syrups, are standard commercial items and are
generally obtained from wheat flour by a variety of water
washing procedures such as that described in Canadian Patent
No. 1,037,474. The various processes are actually relatively
inefficient solid:solid separations in that both gluten and
starch are essentially insoluble in water and consequently,
following formation of a wheat flour dough or batter, the solid
starch is simply washed from the solid gluten which, as
obtained under the processing conditions is in a rubbery/elastic
condition in the form of lumps or the like. These current
commercial proces3es require a large amount of water for batter
preparation and an additional large quantity of water for the
actual washing of the starch from the gluten. During the process,
some of the soluble flour components, such as the pentosans,
simple sugars, soluble proteins, as well as some of the starch,
which is solubilized by indigenous enzymes (such as ~-amylase),
dissolve in the water. However, such potentially u~eful compo-
nents are then lost since they remain in the waste~water. This
soluble fraction generally represents from 6 to 10% of the flour
substance ahd hence is a significant loss.
Moreover, huge volumes of water are used in the process
and consequently the waste waterS contain relatively small amounts
(about 1~ ) of the soluble components. If the waste water is
merely disposed of, i.e. run to sewer, it becomes a major source
of water pollution and, in fact, public authorities are
now frowning upon, if not banning, such practices. An alterna-
tive is to dry, or at least increase the solids content of,
this waste material, a very expensive proposition in view of
the large energy requirements. A further complication is that
many possible profitable uses for the solubles obtainable upon
drying or concentrating are precluded because, in many instances,
114~i8~)0
-- 2 --
the solubles are contaminated with a relatively large amount of
processing aids, especially sodium chloride. ~s is well known,
gluten is by far the most phys~cally functional non-animal
protein and is highly valued on account of that characteristic.
However, that functionality or vitality is lost i.e. the gluten
becomes denatured, in many ways and in particular by heat, and
moreover starch gelatinizes in the presence of heat. Consequently,
the varlous wheat flour washing processes are carried out at
relatlvely low temperatures, generally about 30C, but in any
event ~ignificantly below 60C which is widely considered to be
the maximum to which gluten may be subjected during such pro-
cessing if its desirable functional properties are to be retained.
Moreover, that temperature is also critical from the viewpoint
of the starch in that the latter begins to gelatinize at about
55C. As a result, it would prove virtually impossible to
separate a gelatinized starch component from the gluten component
since the starch would gel thereby making it unsusceptible to
being washed from the gluten.
As stated above, the gluten and starch have many tradi-
tional uses, and historically many of these require that the pro-
ducts be produced to exacting specifications. For example, gluten
is generally produced as vital wheat gluten having a protein con-
tent greater than 75% and usually in excess of 80% and in as
functional a form as possible. As for starch in general, this
is finding new markets as the starting material for the production
of various syrups which are being used to an ever increasing
extent in, for example, sugar replacement, baking and brewing
areas. Purification of syrups is quite difficult and expensive
but for many applications pure, for example clear and non-
coloured, syrups are required. Consequently, since starting with
a purer starch would produce a more pure syrup requiring a less
extensive purification, commercially available starch as used to
produce syrups is utilized in a pure state to produce the
resulting commercially available syrups. In summary, the vast
majority of commercially available gluten and starch syrups
are produced to quite exacting specifications.
However, in many applications, such as brewing (where
the present applicant is a large user of wheat starch and syrup
derived therefrom),such exacting standards of quality are, in
fact, not required butsuch products are used because, in many
6~0
- 3 -
instances, they are the only available suitable products. This
results in increased costs to the user and, when the wider
implications are considered, a waste of resources in the form
of the energy, etc. required to purify the products, where
purification is actually n~necessary~
Processes are known for enzymatically solubilizing and
converting starch tovarious products. For example, United
States Patent No. 2,583,451 teaches a process for producing
dextrose comprising treating pure starch with ~-amylase under
non-gelatinizing conditions at temperatures less than about 45C
and for periods in excess of forty-eight hours. United States
Patent No. 3,922,201 teaches a similar process where granular
starch is treated with a-amylase and glucose isomerase to produce
levulose at a temperature below ~hich rapid gelatinization o~
the starch would take place. The examples teach process times of
twenty-four hours. There are other known processes of a similar
nature, but the process conditions and reactants presently
utilized are such that if proteinaceous components, and in
particular gluten,were present, then such would be significantly
adver~ely affected; for example, in the case of wheat flour, gluten
would be denatured and rendered useless, for example, for baking
purposes; and indeed, might be solubilized to a lessor or greater
extent and cause significant contamination of the syrup and
derivatives thereof and render the products unusable.
An object of the present invention is to provide a
process which, starting with readily available wheat flour,
produce~ a wheat starch syrup and essentially vital wheat gluten
rapidly and relatively inexpenslvely.
A further object is to provide such a process wherein
substantially all of the wheat flour components are recovered
and are incorporated into the process products.
Yet a further objective is to provide such a process
in which waste waters, generally a major polluting factor, are
totally eliminated while at the same time improving syrup yield.
68~)0
-- 4 --
General Statement of Invention
It has now been found that wheat gluten, either per se,
or when present as the protein component of wheat flour, is not
as susceptible to being adversely affected ~y heat as is
presently widely believed in this art.
In more detail, it has been found that the starch fraction
of wheat flour can be liquefied in the presence of the gluten com-
ponent by treatment in aqueous suspension with certain a-amylase
enzymes at significantly elevated temperatures in excess of about
65C for a period of not more than about sixty (60) minutes
without functional denaturation of the gluten component occurring.
Thus, the original solid:solid system is thereby converted to
a liquid:solid system which can readily be subjected to conven-
tional separation techniques to provide the desired syrup and
gluten products.
Detailed Statement of Invention
According to the present invention there is provided a
process for the production of ~yrup and vital gluten from wheat
flour the process including the steps of:
forming a slurry comprising wheat flour, water and an ~-amylase
enzyme which has substantially no protease activity, the slurry
having a pH compatible wlth the activity of the specific enzyme
employed tgenerallY 5 to 71 and contalning less than about 35%
by welght o~ wheat flour;
maintaining said slurry at a temperature of from 65C to about
95C with agitatlon for a period less than sixty (60)minutes but
sufficient to liquefy 9ubstantially all of the starch component
of the flour without signiflcantly adversely affecting the gluten
component; and
subsequently separating the solid gluten from the liquefied
starch syrup.
The process proceeds as follows: the starch gelatinizes
whereupon the ~-amylase commences to act thereon, breaking the
starch polymer down into smaller chain units thus causing liquefac-
tion which prevents the viscosity of the reaction mass from in-
creasing excessively and the reaction mixture from gelling. The
process is completed when the starch has been liquefied to such
an extent that the gluten can readily be removed from the
resulting syrup. In practice this is when the majority of
1 ~4~ )0
~ 5 -
the starch has been solubilized.
The rate of ltquefaction of the starch increases as the
temperature increases. A major limiting factor is the properti-es
of the specific ~-amylase enzyme chosen and in particular the
temperature range, etc. at which lt operates most effecitvely
and, of course, the temperature at which it would be heat-
deactivated. Temperatures within the range of about 70C to
about 95C and especlally between 80C to about 90C are
preferred.
Although, the reaction mass does not significantly
gel, the vlscosity does increase to an extent where the
efficiency of the realitvely small amount of the enzyme in
converting the starch may be significantly impaired. Agitation
of the reaction mass is therefore effected. However, such agita-
tion must be controlled since a high level thereof has been found
to reduce the yield and quality, especially clarity, of the syrup.
To some extent, therefore, the degree/amount of agitation used
depends also on the specific quality of syrup or gluten product
required.
Allied to the above i9 the concentration of substrate
flour in the reaction mass. It has been found that if the concen-
tration of flour exceeds about 35% by weight, then the starch
component is not sufficiently liquefled to be practically separated.
On the other hand, too dilute a slurry would increase the liqui-
factlon time; reduce the capacity of the equipment or necessitate
increasing the size of the equipment; increase handling and energy
costs,etc. Also a major factor is that the present process lends
itself to producing a solubilized starch product, which may be a
~yrup, and which incorporates substantially all the water (and
solubles) and is useable, as ls, since the concentration of
available carbohydrates is at commercially acceptable levels for
many uses without evaporative at other concentration stages being
necessary. Use of excessive amounts of water, i.e. very low flour
concentrates, would result in the resulting syrup being of low
carbohydrate concentration which would reduce its utility in some
areas. Consequently, it is preferred that the starting flour slurry
contain from about 15% to less than 30% flour. It should be em-
phasized that the starting flour material is just that, namely wheat
flour as obtained directly from the milling of wheat with no up-
grading whatsoever being necessary. Consequently, it is readily
~146~
available and at reasonable cost. It is possible to process
flour fractions upgraded in protein but these do not process as
well and are obviously more expensive.
The pH of the reaction mass may vary within the quite
wide limits and is essentially the pH at which the selected
enzyme operates most effectively. However, it has been found
that many suitable a-amylase enzymes operate optimally within
the range of 6 - 7, and most wheat flour slurries~suspensions
have a natural pH of between pH 6 to 7. Consequently, the
reaction mass preferably has a pH of from 6 to 7.
The a-amylase enzyme used mNst be substantially free of
protease activity and, obviously, have the ability to function
at relatively elevated temperatures, in the presence of a
~tabilizing agent (such as calcium chloride and sodium chloride~
if necessary,albeit for only a relatively short period of time.
Moreover, a-amylases which are most active in the pH range of
from 6 to 7 are preferred, sinc~ as stated, aqueous slurries of
wheat flour have a natural p~ within that range and, consequently,
no ad~ustment of the slurry pH is required.
Examples of such a-amylases include certain species of
the Bacillus microorganisms such as 8acillus subtilis and
Bacillus licheniformis. Specific examples of such enzymes are
as follows: f~ 1~
æ (i~ Calbiochem a-amylase - supplied by Calbiochem Co San
Diego, California;
(ii) Sigma a-amylase - a 4x crystallized enzyme supplied by
S~gma Chemical Co., St. Louis, Missouri;
(iii) Ban1120L - suppl~ed by Novo Industries of Copenhagen,
Denmark;
(iv) Tenase - available from Miles Laboratories Inc., Elkhart
Indiana;
(v) HT-1000 - available from Miles Laboratories, Inc.,
Elkhart,~Indiana;
(vi) Termamyl 60L - also supplied by Novo Industries; and
(vii) Takatherm1~ also available from Miles Laboratories Inc.,
Elkhart, Indiana.
ti) to (v) belng derived from ~. subtil~s and (vi) to ~vit
being derived ~rom 3 licheniformis.
68~
- 7 -
The concentration of a-amylase enzyme required is
relatively small and obviously depends on many factors, especially
the activity thereof and the process temperature. As the
specific experiments detailed later indicate, there appears to
be a minimum concentration of enzyme if complete liquifaction is
to be achieved and that minimum can easily be found via simple
experiments as described herein. For example, the following
concentrations have been found satisfactory.
(a) Ban 12~L - 1 ml to 2 ml /100 g flour,
activity being 120 KN~g;
(b) Calbiochem - > 0.05~ by weight, activity being 1477 AU/g;
(c) Termamyl 60L - > O.5% by weight, activity being 60 KNU/g
Of course, an amount of enzy;me of suitable activity must
be used; in other words the activity and amount of enzyme must
be suf~icient to effect the necessary solubiliation within the
stated process parameters. That amount of enzyme is termed "the
effective amountnand is readily determined for each sel~cted enzyme
using the general lnformation given herein.
In the accompan~tng F~gures:
F~g. l is a curve of conversion t~me ~ersus temperature
for Termamyl a-amylase;
Fig. 2 is an activity curve obtained using Calbiochem
a-amylase and various pH values;
Fig. 3 is a flow sheet wlth mass balance of an embodiment
of the invention using Calbiochem ~-amylase;
Fig. 4 is similar to Fig. 3 but wherein agitation of
the gluten product is carried out; and
Fig. 5 is a similar curve to Fig. 1 but wherein the
enzyme is Sigma a-amylase.
:~468~0
- 8 -
The present invention will be further described withreference to, but not limited by, the following specific experiment:
Experimentation
The process of the present invention as described in
B the following Examples was carried out in a CHAIZ (Nancy, France)
apparatus, orig~nally intended as a brewery laboratory mashing
un~t. The apparatusincorporates a temperature controlled bath in
whlch reactlon cups are lodged and allows for agitation of the
reactants via a stirring mechanism which, during all the Examples,
was set at 200 r.p.m.
Separation of the s~rup and gluten was effected by
centrifugation using a SORVAL RC-3 HGA swinging buc~et head
centrifuge. However, other conventional separation techniques such
as filtration and even sedimentation can be used, the choice
depending to some extent on the required degree of separation of
the li~uid from the solid phase and the specific constitution of
the liquefied starch and gluten product(s) required.
Procedure
A predetermined quantity of flour (usuallylOOg) was
mixed with water, (in the ratio of 1:4 unless otherwise stated)
and the selected enzyme~ ~ where required in combination with an
accompanying stabilizing mixture of calcium chloride and sodium
chloride) was added. The resultlng suspension was
plac~din the CHAIZ, where the temperature of the bath had been
adjusted to the desired value and the stirring immediately started.
The mixture was held, with stirring, at the set temperature for
the duration of the process, following which, any further reaction
was arrested by rapid cooling. The mixture was then centrifuged
to obtain the heavier gluten and as the top phase, the liquefied
starch.
In an alternative embodiment, the gluten was re-washed
and centrifuged again, the second liquid phase (comprising a very
dilute liquefied starch being used as the flour slurry ma~e-up
water.
The experimental w~rk carried out to delineate the effects
of temperature on the process of the present invention showed
that the process was ameniable to being effected over the range of
from 70 to up to about 95C, the results at higher temperatures,
whilst showing greater conversion efficiency in terms of
~46800
_ g
reduced processing times, also indicated that the liquefied starch
and gluten products were not signficantly altered from the products
at the lower temperatures. Since the available equtpment was most
conveniently operated at temperatures of about 70C to 80C with
little effect on the experimental time required, evaluations
of other process parameters such as enzyme concentration, etc.
were in many instances carried out at temperatures within that
range.
In addition, standard operation of the CHAIZ unit
allowed only for batch-type processes and consequently, much of
the w~rk effected was of that type. However, all indications are
that no problems of substance would be encountered on carrying
out the process of the present invention on a continuous basis.
Indeed, from a commercial viewpoint, that would be the pr~ferred
mode of operation and the design of suitable e~uipment would
present little difficulty.
Process parameters which are important to the efficient
carrying out of the proces~ of the present invention include:
(a) temperature
~b) enzyme concentration
(c) flour (substrate) concentrate
(d) pH
(e) flour type
Each specific enzyme i9 unique to some extent as
regards degree of activity, optimal processing conditions of
pH, temperature, etc., and consequently, in practice the actual
process, in terms of the ~pecific values of each parameter, will
be tailored to suit the specific enzyme. The experimentation work
detailed herein does not, obviously, provide such data for each
and every possible ~-amylase. However, the extensive data is
fully sufficient for a man skilled in the art to determine, with
a few simple experiments, the processing conditions to be most
advantageously used with any selected enzyme.
~6800
-- 10 --
Effect o~ ~eat, per se, on ~ital ~heat ~-luten
In this experiment the effect of heat, per se, on vital
gluten was determined by reconstituting standard regular vital
wheat gluten (obtained from IGP Limited, Montreal) with distilled
water and, following reconstitution, maintaining a first sample
at 80C and a second sample at 9~C for two hours, following which
the samples were cooled and dried and their functional vitality
compared with a regular vital gluten control.
The surprising result was that there was no signiflcant
difference ~n vitality between the heat treated samples and the
controls. It was from this surprising finding that the realiza-
tion that wheat flour could be subjected to a relatively high
temperature / short time process and, on that count alone, the
gluten component would not be denatured.
Gluten Ball Test
In order to determine rapidly and in a convenient manner,
if an a-amylase sample is suitable to be used in the present
process, a simple test was devised. A number of gluten balls were
made by mixing commercial regular wheat gluten (lOg) with water
(12g), the latter containing the enzyme to be evaluated for the
desired efficacy. The balls were tested over a period of time by
each being squeezed manually w~th the fingers . If the~enzyme under
test had a sing'ficant protease activity, this manifested itself
by causing the balls to soften and lose vitality. In the test,
regular vital (80% protein) gluten scores 5 and O indicates no
vitality as indicated by a lack of elasticity.Although this test is
subjective to some extent, it is, in fact, quite reliable and able
to be utilized by any person skilled in this art. Its reliability
was confirmed in that, of the a-amylases tested, Calbiochem ~-
amylase gave the best result - that enzyme did not affect the
vitality of the gluten ball even following a five (5) hour
incu~ation period at room temperature. Later analysisrevealed that
that enzyme had a protease activity of only 0.4 AU/gm, by far
the lowest of the enzymes tested and quite insufficient to
adversely af~ect gluten vitality even over an extended period.
Another enzyme indicated by the test to be superior and therefore
preferred was the Sigma ~-amylase.
~46~3~0
-- 11 --
Process Parameter Evaluations
Section A - using Termamyl 60L, supplied in liquid form having
an activity of 60 K~u/~.
Temperature
A series of experiments were conducted to determine the
effect of temperature on the present process. The process was
carried out at the following temperatures:
65C: 75C: 80C: 85C: 90C: 95C
The substrate was Glenrose flour ~Ogilvie ~ r Mills,
Montreal) having the following composition:
Protein 9.53
Starch 82.30
Solubles 2.32
Moisture 11.88
On each occasion, 100 g of flour and 1 ml (equivalent
to 0.05%) of enzyme were charged to the reaction cup. The time
was noted for completion of the reaction to total starch disapp-
earance, this being determlned by the standard iodine test for
detecting starch. The result~ are given in Fig. 1.
The results show quite clearly that the time required for con-
version reduces drastically as the temperature is increased
especially to temperatures over 80C.
EnzYme Concentration
Using the reactants as detailed above, a series of
experiments were conducted to determine the amount of Termamyl
60L required for efficient conversion. The results are contained
in the following Table 1 .
Table 1
_ Enzyme Concentration
Temperature 0.5% ¦ 1.0~ ¦ 1.5
65C 120 min. 120 min.
80C 60 min. 36 min. 28
90C 11.5 min. 9.5
* Flour suspension not completely liquefied
~1~6~3VO
- 12 -
The results show that about 1% (by weight based on the
flour) of the enzyme is effective. If the amount of enzyme
is less,the tLme required at low temperatures becomes prohibitively
long whilst at high temperatures the starch did not completely
liquefy. Increasing the enzyme concentration gained little in
terms of reduced conversion time. Moreover, the excess enzyme
could actually be detrimental in that, if the enzyme used does
have (even a small) protease activity, the total protease may be
increased to a level where it may have significant adverse
consequences on the gluten protein.
6uhstrate ~lour) Concen~r~tion
A series of experiments were conducted to determine the
effect of flour concentration on starch conversion
efficiency using the Termamyl ~-amylase at a constant level of
1 ml enzyme solution/100 g ~uffaloflour; the concentration of the
latter being varied as follows:
20~: 25%: 30~: 35%: and 40~
The results are included in the following Table ~
Flour
conc. ~ 20 25 30 35 40
._ ...
Iodine Reaction neg neg trace pos pos
Syrup Weight (g) 264.0 253.3 241.0 209.4 188.3
op 17.27 21.69 35.80 29.20 32.13
Extract in Syrup
(g) 45.6 54.9 62.2 61.1 60.5
. _ .
The re~ults show that at flour concentrations of about
35~ or more, starch liquifaction is inadequate, ~under the stated
condittons which are within the optimum range for the enzyme ~n
question), to the extent that separation of the gluten would prove
impractical. The maximum of about 35~ of flour in the starting
slurry ls generally applicable.
6800
.The gluten products obtained in those experiments were
analyzed and the results are given in Table 4 below:
l ml BAN enz~ e (b)2~ml BAN enzy~ë
40 min. at 80 C 22 mtn. at 80 C
... . .
Protein, % 55.19 67.38
Total lipid, % 8.83 11.27
Pentosan, % 23.96 9.68
Starch, % 15.18 4.73
Ash, ~ not determined 1.89
Both gluten products were ~unctionaland product (b)
proved similar ln baking performance to xegular vital gluten.
Influence OfFlour TvPe on Products
~p1
B In this experiment Buffalo, Harvest Queen and Glenrose
flours of the following compositions were processed according to
the present in~ention:
. _
Component Buffalo Harvest Queen Glenrose
. . . _ .__
Protein ~%) 14.14 12.20 9.53
Moisture (%) 9.5 11.37 11.88
Starch ~,db) 69.51 73.02 82.30
Solubles (%) 1.98 2.24 2.32
Ash (%)0.85 0.51 0.43 .
The BAN 120L ~-amylase was used in a concentration of
2mlflOOg flour and at 50C, and the resulting syrup and gluten
separated by centrifugation in the usual manner.
Analysis details of the syrup and gluten products
o~tained are contained in the following Ta~le 5
~3
- 114t:~8~)0
Table 5
~ufe~lo Queen Glenrose
Syrup Degree 16.3 16.3 17.3
~ Protein
in syrup
~solids 3.2 3.1 2.5
Gluten Yield 17.2 14.3 10.7
.
Protein
(d.b.) 67.7 68.2 61.2
Gluten
Ball Test 1-2 0-1
Conclusions
-
(i) The Glenrose flour gave syrup having the highest plato value
but the lowest gluten yield which was also the lowest in quality
(vitality) of the three sample~.
(ii) The Buffalo flour gave the hlghest gluten yield.
(i~ and (li) are not unexpected since Glenrose is high in
starch/low in protein whereas Buffalo i5 high in protein but
relatively low in starch. However, the Buffalo-derived gluten
also had the most vitality.
Section C
Experiments utilizing the Calbiochem enzyme supplied
in crystalline form and having an activity of 1477 AU/mg.
(i) Enzyme Concentration
A series of experiments utilizing increasing concentra-
tions of enzyme were carried out, enzyme concentrations being:
1 4
1.146~)0
-
0.025%: 0.050%: 0.075%: and 0.100%
The flour used was Buffalo and all the experiments
were carried out at 70 C with a liquefaction time of sixty (6)
minutes.
Results
(i) At the 0.025% level, a positive iodine test indicated that
the reaction was not completed.
(ii) The sample at the 0.~5% level gave a trace iodine test but
all enzyme levels above 0.05% gave a negative results i.e. the
reaction was complete.
(iii) Consideration of the syrup gravity values, yields of gluten
fractions and protein contents of such fractions indicate that
enzyme levels above 0.05% were adequate and, indeed, this was
confirmed when the gluten ~all test indicated that the gluten
obtained at the higher enzyme levels was in fact better, i.e.
more vital, etc.
~ii) pH Effect
A ~eries of experiments were carried out utilizing the
Calbiochem enzyme at the 0.05~ level in a Buffalo flour:water
, (1:4) slurry at 70C for sixty (60) minutes liquefaction period,
the pH of the slurries (adjusted using hydrochloric acid or
sodium hydroxide as necessaryt increasing as follows: 4.5: 5.0:
5.5: 6.0: 6.5: and 7.
The results are included in Fig. ~ and show that the
optimal pH for this enzyme is from 6 to 7 this giving the highest
starch conversion tto a 16.5P syrup) and optimum gluten quality,
both protein content t64-65~) and ~itality. Since flour/water
su~pensionq ha~e a natural pH of about 6.05-6.10, no adjustment
of pH is really requtred and throughout this specification all
flour:water slurries have a pH of from 6.0 to 7.0 unless other-
wise stated.
(iii) Full Process
Again utilizing the Calbiochem enzyme, the process
was carried out whereby 1200 g of Buffalo flour in a 1:4 aqueous
slurry was acted upon by 0.6g of enzyme at about 70C for thirty
(30) minutes.~ The process showing full mass balance is shown in
Fig. 3 . As can be seen, some refinement to the basic process
was made - in particular the initially obtained gluten fraction
- 1~4~8~0
Gi was washed resulting in the generation of second gluten fraction
G2, the wash water Wl being used as slurry make-up water, the G2
gluten fraction was comprised of two products as obtained
from the centrifuge,whiCh products are subsequently freeze-dried
as products Pt and Pb(~n summary,the products obtained are:
l Yield (g~ op ¦ % Protein (db)
. _ , . .
Syrup Pl 4,896 16~72
Syrup P2 5~073 2.56
I (recirculated as
I make-up)
GlutenProduct, I 44.03
GlutenProductl ' 70.02
The major gluten product Product A had the following
composition:
Co~ponent ~ (dry basis)
Protein 70.2
Lipid 9.46
Starch 4-45
Ash 1.08
Pentosan 5.17
This product had a vitality, as measured by the gluten
ball test, e~uivalent to regular vital gluten. Moreover, this
was conf~rmed via bread baking trials - refer Section E below
1~
11468~)0
Effect of Washing With and Without Agitation of the Gluten Product
It was noticed that some starch remained in the
insolubilized gluten fraction. This fraction was, therefore,
subjected to a washing step prior to separation by centrifugation.
The experiment used 50 m~ Calbiochem enzyme (with 5.5 mg CaCl2
and 2.75 mg NaCl) per 100 g flour, a conversion temperature of
70C and a period of thirty t30~ mlnutes.
The results are contained in Table 6.
Table 6
= Agitation
~aring Blender No Agitation
_ t2 min/med tum~ .
Flour UsedBuffalo S.SP2 * B.uf.falo SSP2*
proYrUF Weight(g)409.0 405.0 407.2 404.0
op 16.74 16.32 16.63 16.30
ClarityHazy Cloudy Hazy Cloudy
Gluten Weight(g)
Products
(nfnaltyPeri~ 4.25 4.00 2.55 3.35
effected)
bottom13.20 14.60 17.5 18.0
(% db)77.12 78.22 68.76 68.56
Ball test4+ 4+ 4 4
The exper~ment was repeated on a larger scale and the
results of the second experiment are contained in Table 7,
the flow diagram with mass balance for the latter being shown in
Fig. 4.
* ExFerimental hish extract blend of Ogilvie Flour Mills.
17
11~6~300
Table 7
Weight, g ¦ 412.3
Syrup Product degree plato,P ¦ 16.31
clarity ¦ clear
. _ _
Gluten top layer Weight (g) 4.21
Product B
Moisture (%) 3.06
Protein (% db) 39.07
Total lipid 7.33
Pantosan ~ 25.17
Ash ' 1.95
Starch ~ 14.02
1.
Gluten bottom layer Weight (g) ~ 13.29
Product C
Moisture (%) 1.37
Protein (~ db) 75.96
Total lipid 10.16
Pentosan 2.33
Ash 1.02
Staxch 1.6
The results clearly show that the additional washing step or
operation not only greatly improves the starch syrup/gluten
separation efficiency but also gave a better gluten product.
Again, this was confirmed via baking trials using the products
B and C of Table 7 - Section E.
(iv) Purification of Gluten Product
Although the products, and in particular the gluten
products, of the process of the present invention are intended to
be utilized with little or no purification, the gluten products
can be upgraded if desired.
18
~68~)0
For example, 100 g of Buffalo flour was treated with
400 g water containing 50 mg Calbiochem ~-amylase at 70C for
thirty (30) minutes and the resulting syrup and gluten separated
by centrifugation in the usual manner. The wet gluten obtained
was dispersed in water (made up of 500 g) centrifuged; the clear
wash water removed as was the top white (carbohydrate) layer.
That procedure was repeated five (5) times. The result was vital
gluten having a protein content increased to 77.8%. Although
the white l~yer was positlve to iodine and hence lncluded some
starch, it was composed mainly of non-starch material.
Section D
Using Sigma 4-x crystallized enzyme having an activity
of 1270 U/mg.
In a similar fashion to Section C(ii), a series of
experiments were conducted using Sigma enzyme at the somg level,
a Buffalo flour/water 1:4 slurry, liquefaction temperature of
70 C for a period of sixty t60) minutes. The pH values used
were:
1 9
~468~)0
4.5: 5.0: 5.5: 6.0: 6.5: and 7.0
The results are givenin Fig. 5.
Once again the optimum range as far as starch conversion
(about 14.75P syrup produced~ and better gluten, high protein
content of 64-65% and good vitality, is concerned is for 6.0
to 7Ø
ComParison of Calbiochem and Siqma Enzymes
In a series of experiments, these two enzymes gave very
similar results, the only noticeable difference being that the
Calbiochem had a somewhat higher activity.
section E
Evaluation of Gluten Products
Three gluten products of the present invention, in particular
those produced according to the procedure described in
Section C ~iii) - Product A
Sectlon C ('iii) - Product B
Section C (iii) - Product C
were tested to determine their performance in breadmaking.
Three gluten products had the followinq chemical composition:
Table 8
.
Product "A" Product "B'' Product "C"
Washing with agitation No Yes Yes
Dry gluten productBottom Layer Top LayerBottom Layer
Protein content % 70.0 39.1 76.0
Total lipid % 9.5 7.3 10.1
Starch ~ 4.3 14.0 1.7
Ash 1.1 ¦ 2.0 1.0
Gluten Ball Test 4 0 1 4+
Yield of gluten % (d.b. 17.3 4.5 ~ 14.5
~46800
Bread samples were produced using the recipe and
procedure given below, regular vital gluten being the control.
Results
(i) Gluten A could replace up to 60% of regular vital gluten
in bread making without any noticeable change in either bread
volume or internal structure, the protein level remaining the
same. Greater than 60% replacement resulted in a decrease in
loaf volume and a crumb having a coarse, immature appearance.
(ii) Procedure B could replace up to 25% of regular vital
gluten without noticeable effect. At levels above 25%, the
dough molding became light, poor "oven spring" was apparent
and smaller loaf volumes were obtained.
It may be noted that Product B had a low protein content
and scored very poorly in the gluten ball test and yet could
still replace up to 25% of regular vital gluten, which is ver~
significant from a practical economic viewpoint.
(iii) Product C was, to all intent and purposes, the same as
regular vital gluten obtained by conventional processes. It
could replace up to 100% of regular vital gluten with no
noticeable changes in loaf volume, etc.
As indicated above, a major aspect of the present inven-
tion is the realization that a staple item of commerce, wheat
flour, which is readily available at reasonable cost, can be
rapidly converted into syrup and gluten products. Moreover, the
proce5g i9 very flexible in that it can be tailored to produce
syrup and gluten products for sepcific applications at relatively
low cost. For example, carbohydrate syrups can, and are, used
in the brewing industry as replacement for conventional adjuncts
such as corn grits, etc. inter alia on account of convenience,
consistency, etc. of the syrups. The syrups for use in this
applications require a Plato ~alue of from about 10-16 P. More-
over extreme purity, especially as regards clarity, is not of
great importance. Such a product is ideally suited to being
produced by the present process at low cost.
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11468~0
-
Turning to gluten products, an obvious application is in
the baking industry where large amounts of gluten are used,
both solely to improve the protein content of the flour and in
some instances to improve the protein content and to assist the
indigenous protein in fulfilling its traditional role. As stated,
the gluten products produced according to the invention may range
in functionality from poor to as good as regular vital gluten,
depending mainly upon the choice of starting flour but also on
whether the product, as obtained directly from the process, is
subjected to a washing procedure. Even the less vital but still
functional to ~ome extent gluten produced by the process of the
present invention can be utilized to replace a significant propor-
tion of the more expensive regular vital gluten as the baking
trials demonstrate, and the present invention allows such pro-
ducts to be produced relatively inexpensively and at will. As
regards, the latter, the plant required to carry out the process
of the invention, especially on a continuous basis, can be
relatively inexpensive both in capital and to operate.
Moreover, it readily lends itself to bein operable on a
"when required" basis. In other word~, there will be es~entially
no delay between the demand for product syrup and/or gluten
arising and the product being supplied. If the plant is operated
to provide, as required, only one of the two products, then the
other product can be collected and stored for shipment. It is
anticipated that the plants would be custom built for a
single location such as a single brewery or bakery and consequently
no large inventory of starting flour or storage for product would
be required. The manpower required for such a plant would be
minimal and would be employed on other duties when the plant
iQ not being operated.
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