AU427367B2 - Readily dispersible dry gluten product processes for making it, and uses thereof - Google Patents

Description

27,364171

BACKGROUND OF INVENTION Field of Invention This invention relates broadly to a novel gluten product, processes for obtaining it and uses thereof. More particularly, this invention is concerned with a vital wheat gluten product of novel physical structure endowing it with improved functionality, to processes for producing it and to its utilisation in making different products, especially, though not exclusively, yeast-leavened bakery products;. Description of the Prior Art

Vital wheat gluten (sometimes referred to herein, for convenience, simply as gluten), is a concentrated natural protein in the form of a light tan powder having a bland taste and aroma. It usually contains 75% to protein, 6% to 8% fat-like phospholipids and related 2. 427.367

27,364171 compounds, some fiber, residual starch, a small amount

of mineral matter and between 4% and 6% residual moisture.

It is normally insoluble iftneutral aqueous solution

(pH 4 to For commercial purposes, vital wheat gluten

is presently manufactured by one of several washing

processes in which wheat flour is kneaded with water to

remove the starch and water-soluble materials from the

gluten. This gluten forms a tough, rubbery elastic mass

containing a high proportion of water. This water must

be removed rapidly without exposing the gluten to excessively

high temperatures, since gluten, being a protein, can be

denatured by exposure to high temperatures when in the wet state. Two drying processes are in common use, one

involving spray drying'and the other flash drying. The

gluten from the former'method tends to be finer than the

flash dried gluten which, typically, has an average particle size of between 5 and 75 microns. Vital wheat gluten is an increasingly important

product of commerce, especially widely used today in the

manufacture of yeast-leavened bakery products such as bread, rolls and buns. In this application, it supplements the

natural flour protein where added strength is needed or

desired for one or more of several reasons, say, to build

stronger sidewalls in expanded-white bread, or in the

production of variety breads where the non-flour proteins

dilute the flour protein to such an extent that the latter protein cannot function satisfactorily without

supplementation. It is also used in other food applications.

For instance, it is used to increase the protein content,

and hence the strength, of pasta-like products such as 427.367

27, 3 6 4 7 macaroni, and in the manufacture of dietary wafers. it is also used as a binder or diluent in pharmaceutical tablet

formulations. 'The utilisation of vital'wheat gluten in applications such as the manufacture of yeast-leavened .bakery products, is being hindered on account of the fact that gluten is not free- flowing or readily dispersible when added to water, and the

dispersion, once obtained, is not very stable, since the gl uten

particles have a tendency to lump and agglomerate.- It is believed that this characteristic poor dispersibility can be

attributed to two distinct, but inter-related phenomena. Firstly, powdered gluten is highly hydrophilic so that upon'

initial wetting it hydrates rapidly to form discrete lumps consisting of a dough-like outer wall, which resists further

moisture penetration, encapsulating a core of essentially dry

unaltered powdered gluten at-the center. These lumps can be smoothed out and broken up, though vigorous agitation is needed for this purpose. However, the disintegration of thie lumps and dispersal of the particles is accompanied by the wetting of individual gluten particles. These individual, wetted particles, because of significant inter-molecular

forces, exhibit cohesion so that they tend to coalesce, when

they can be separated only by the exertion of considerable

disruptive forces. Accordingly, a dispersion of ordinary powdered gluten once obtained is markedly unstable because of this tendency for coalescence between individual gluten particles. Whatever the theoretical explanation, it is a fact, that on mixing vital wheat gluten with water, a lumpy product

is obtained which, on vigorous agitation, is transformed

4 427,367

27,364171 elastic mass. into a high intractable, rubbery, past to Efforts have been made in the the poor dispersibility of. overcome, or to improve-upon, In essence, prior practice powdered vital wheat gluten. or coating the has involved intimately incorporating, selected powdered gluten with a small amount of certain Lipids that have been used materials, notably lipids. hydrophilic lipids like for this purpose include non-ionic of lactylic esters of fatty monoglycerides, edible salts stearyl monoglyceride acids, polyoxyethylene stearate, protective barrier or surface citrate, which provide a between particles of layer serving to reduce coalescence the present time, a gluten the thus-treated gluten. At lipid, believed to be the coated with such a hydrophilic is commercially monoglyceride, glyceryl monostearate, that is effective to the extent available. -This material to a marked degree the the hydrophilic lipids alleviate treated gluten tends to form cohesion problem so that the once dispersed. However, a relatively stable dispersion gluten is of poor it is found that the thus-treated added to water it does not wettability so that on being tends to form a lumpy mass, disperse readily but instead agitation in order to requiring relatively vigorous particles. disperse the individual gluten because of the presence Also, the treated gluten, in expensive, material often of an additional, relatively around which needs to substantial amounts (typically controlled process, is be applied in a carefully the on a gluten basis than significantly more expensive This is a considerable untreated powdered gluten. 42 7.367

2719G4 71 deterrent to its widespread adoption by, for instance, the

commercial baker who operates in a markedly cost conscious and highly-.competitive industry. This is further aggravated by the fact that the presence of a substantial amount of an

extraneous material reduces the effective amount of gluten,

the component of primary interest to the baker, in a given

weight of the product; this markedly reduces the water adsorp- tion of the gluten product, and can complicate the baker's standard formulations and procedures. Furthermore, the materials used in the treatment may detract in one way or an- other from desired properties in the food or other product in

which the treated gluten product is incorporated. StfIMARY OF THE INVLNTION

The present invention consists in a dry vital wheat gluten product in the form of coarse, porous, irregularly-shaped agglomerates composed of a multiplicity of individual gluten

particles adhered together in a random form and array, the

major proportion of the agglomerates having a particle size

exceeding 149 microns, the gluten product being further charact- erised by the ease with which it can be dispersed in neutral aqueous dispersion (about pH 4 to about pH 8) simply stirring

to form a relatively stable dispersion in such a medium. T he present invention further consists in a process for

Improving the functionality of vital wheat gluten particles

wit'nout-denaturing the gluten, comprising exposing the individual gluten particles in a:treatment zone to the action of an ag-

glomerating agent so as to render the surfaces thereof sticky,

commingling the superficially agglutinated particles while dispersed in such a treatment zone thereby causing them to adhere

together in the forim of coarse, porous agglomerate-s of random 6 427.367

27. 36 4 shape and form with a majority of a size greater than 149 microns, and drying the agglomerates to adjust the total

residual moisture content to less than about

The present invention still further consists in a process of producing yeast-leavened bakery products, which

comprises incorporating along with the standard dough in-

gredients including flour, shortening, sugar and salt prior

to baking an effective amount up to about 10% by flour-weight

of an agglomerated gluten product in the form of coarse, porous, irregularly-shaped agglomerates composed of a mult-

iplicity of individual gluten particles adhered together in a

random form and array, the major proportion of the agglomer-

ates having a particle size exceeding 149 microns, the gluten

product being further characterised by the ease with which it can be dispersed in neutral aqueous dispersion (about pH 4 to

about pH 8) by simply stirring to form a relatively stable dispersion in such a medium.

The present invention still further consists in a yeast- leavened doughs containing an effective amount up to about by flour weight of an agglomerated gluten product in the form

of coarse, porous, irregularly-shaped agglomerates composed of a multiplicity of individual gluten particles adhered together in a random form and array, the major proportion of the ag- glomerates having a particle size exceeding 149 microns, the gluten product being further characterized by the ease with

which it can be dispersed in neutral aqueous dispersion (about pH 4 to about pH 8) by simply stirring to form a relatively

stable dispersion in such a medium.

DETAILED DESCIPTION OF INVNTION

Additional features of this invention will appear from

S427.367

27 36 4 71 the following description in which reference.will be made to the accompanying drawings in which: Figure 1 is a flow sheet illustrating in a general way the process of making the gluten product of this invention; Figure .2 is a schematic view of a preferred apparatus assembly for making the gluten product of this invention; Figures 3 and 4 are photomicrographs serving to illustrate the characteristic porous, agglomerate structure of the improved gluten product in contrast with the individual particle characte of ordinary commercially available vital wheat gluten; Figure 5 is a graph illustrating the results of sieve analyses of the agglomerated gluten, ordinary powdered gluten an a treated powdered gluten product of the prior art; and Figures 6 and 7 are photographs serving to illustrate the improved dispersibility of the agglomerated gluten in contrast with ordinary powdered gluten and a treated powdered gluten pro- duct of the prior art; Referring now to the flow sheet of Figure 1 of the accom- panying drawing, the gluten starting material can be of any particular, conventional type, whether spray or flash-dried, and is characterised by its fine powder form and its non-free-flow- ing properties reflected in a poor dispersibility, and a pronoun- ced tendency for particle coalescence in neutral aqueous media. The individual gluten particles vary considerably in size depend- ing, to -soe degree, on the method of preparation. However, in a typical sample the particle size would range from about microns to about 180 microns (average particle size 150 microns) This gluten is then subjected to a special treatment wherein the individual particleo are exposed to the action nf an ag- glomerating agent so as to render the surfaces thereof sticky. 8 42 7.367

27.3641 are then brought into The superficially agglutinated particles as to cause them to adhere intimate contact in such a way of random size and irregular together in the form of aggregates greater than the size shape, but always of a size substantially the initial gluten. The of the individual particles constituting

agglomerates

427.367

2)7, 36 4 171 are then dried to adjust the final residual moisture

content to the pref erred level of less than about

Thereafter-, the material is classified, and agglomerated gluten of the desired size and structure is delivered as a finished product and suitably packaged. Non- agglomerated'and oversized material is recycled. The agglomerated gluten structures so-obtained are sufficiently

strong and firm to withstand normal handling without

giving rise to any serious disintegration problem.

In the wetting and drying steps, the conditions of time and temperature are selected .and controlled to

avoid any deieterious effect, as would, for instance,

obtain were the gluten denatured, on the functional*

properties of the gluten in supplementing protein in food

applications.. Usually, the/we4-.ii agent is either a liquid which, on contact with the gl uten, renders the gluten.

particles tacky and causes them to adhere together in

clusters following cont act, by hydrating part or all of the gluten or otherwise transforming it to obtain this

effect, or a solution or suspension of some ingredient ini

a liquid, such, for example, as sugar solution, so that

this ingredient itself performs the agglomerating function.

Conveniently. the/wetkin agent is water or water. vapor, though other substances such, for example, as

ethanol, formic aci d, acetic acid and ammonia may be used.

In a preferred embodiment of this invention, the gluten particles are superficially agglutinated with the

Z'/wet-t.-tng agent, agglome~ated and dried almost instantaneously 4427.36G7

27,,364 171 in a single treatment zone, thus eliminating any need to transfer the wet sticky agglomerates from an agglomerating zone to-a drying zone. This may be achieved by:

Forming the powdered gluten into a fluidized

bed; (ii) Maintaining the bed in a particulate fluidized

state by passing a fluidizing gas, such as compressed air, upwardly through the bed;

(iii) Discharging an agglomerating agent in atomized form directly into the particulates, fluidized bed between the top and the bottom thereof. This agglomerating agent agglutinates the surfaces of the particles which are commingled,by the gentle agitation of particles in the bed, to an extent

sufficient to cause such particles on contact with adjacent particles to adhere together in the. form of moist, irregularly-shaped agglomerates;

and (iv) Drying the agglomerates by means of the fluidizing gas, typically, by evaporation of theliquid therefrom. The wetting, agglomerating, and drying follow in

sequence but take place substantially instantaneously, and the agglomerates are then removed from the chamber. This preferred process will be further described with reference to Figure 2 of the accompanying drawings which schematically illustrates a suitable apparatus assembly

wherein it may be performed. Referring to this Figure, the apparatus assembly includes a supply hopper 11 for storing the powdered gluten

11. 427.367

27,364P'7 and a reactor 12. This reactor is a vertical, cylindrical structure divided by a perforated diffuser plate 13 into an upper zone wherein the fluidized bed 14 is formed, and a

lower zone in the form of -a-plenum chamber 15. A downwardly- extending duct 16 is provided in the roof of the reactor to

receive the gluten from the supply hopper. An upwardly- extending duct 17,*also in the roof, is provided-for the egress of the fluidizing gas, say, compressed air, from the

reactor. The duct 17 connects with a dust collector 18 and a blower 19 and a downwardly extending duct 17' connects the'dust collector to the-reactor. Interposed in each of the downwardly' extending ducts 16 and 17' are rotary air locks 20 and 21. The floor of the reactor includes a dischag duct 22 for removal of the gluten, a major proportion of which normally will be in an agglomerated state. The discharge duct leads to a screw conveyor 23-, fitted with a variable speed device to.

Dermit control of -the discharge rate, and a sifter 24.' Located in the wall of the -reactor, in a median position,

are a series of atomizing nozzles, one of x~hich, 25, is

shown, for introducing droplets of the/we4t4ing agent directly into the fluidized bed 14 located in the upper

part of the reactor. The preferred system involves gas atomization. In the wall of the plenum chamber 15, below. the atomizing nozzles, a duct 26 is located for introducing the fluidizing gas into the chamber. This duct is connected to a heater 27, a pump 28 and an air filter 29.

In obtaining the novel gluten product of this

invention using the foregoing apparatus assembly, dry powdered gluten, usuall~y with an average particle size of about 50 microns, is continuously fed from the supply V 12 427.36-7

2713 6411 hopper 11 into the upper part of the agglomeratingq reactor

12 ate a rate which will maintain the desired dimensions of the fluidized bed 14 into which the gluten particles enter.

The gluten in the bed is maintained in a fluidized state by passing heated air or a heated inert gas like nitrogen

through filter 29, pump 28, heater 27, duct 26, plenum chamber 15 and diffuser plate 13 defining the bottom of

the bed. The gas should be passed through the bed at a

rate exceeding that required for incipient fluidization

of the gluten. in most instances, the minimum velocity

required to maintain the bed in a fluidized state is about

feet per minute Usually'the flow rate is

adjusted and controlled at between about 40 and about preferably between about 50 and about 70 f.p.m.

The temperature and flow rate of the fluidizing gas, which is

heated on passage through the heater 27 should be controlled, i njunction with the temperature and flow rate of the ,~w4~4t~agent to ensure that the gluten is not denatured as 0 it would were the temperature to exceed about 60 and

the agglomerated gluten product is of the desired moisture

content. Conveniently, the temperature of the fluidizing

gas is controlled at between 100* and 150*C., and the bed 0 temperature at between 45* and 55 C. After traversing the fluidized bed, the air or

inert gas leaves the treatment chamber through the duct 17 leading to dust collector 18. The air or inert gas is

exhausted from the dust collector by a blower 19 which is so designed and regulated as to maintain a slight vacuum between about 2-4 inches U 2 0 in the upper part of the

reactor). Gluten recovered from the gas by and in the dust 427.367

27,36 4 7t collector is returned directly to the chamber through the rotary air lock 21. The agglomeration agent is introduced directly into the interior of the fluidized bed through the atomizing nozzles 25. Conveniently, the agglomerating agent is water, though a solution, slurry, emulsion or dispersion in water of.any material that it may be desirable to add can be used. The agglomerating agent is fed to the atomizing nozzles at a uniformly controlled and predetermined rate based on the quantity of liquid that is required, at a given reactor temperature (not above 600C.) and flow rate for the fluidizing gas, to effect satisfactory agglomeration and that, in addition, can be evaporated to yield gluten agglomerates of the desired size, structure and properties. Usually, the flow rate is between about 1 and about 4 gallons per hour for each nozzle, and the gas which usually is used to atomize the agglomerating agent is at a pressure of between about 25 to about 80 Rs.i.g., giving a droplet size of between 10 and 250 microns, preferably between 10 and 100 microns. The water or other liquid in the agglomerating agent is immediately evaporated and carried off in the fluidizing gas passing out of the chamber. A mixture of agglomerated and non-agglomerated material, i.e. gluten powder, is continuously withdrawn from the fluidized bed in the agglomerating chamber through the discharge duct 22 and variable speed screw conveyor23 which permits control of the discharge rate. The optimum discharge rate depends on several factors such as desired size of the agglomerates, and the nature of the agglomerating IA 4 2 7.367

2 7,36 4I171 agent, which must be determined in each instance by

conducting-a few trial runs in which the several variables are adjusted until the optimum is located. The residence

time of the gluten particlesin the fluidized bed should

be so controlled that the gluten is not adversely affected.

The mean residence time is usually of the order of 15 to minutes.

The mixture is then/conveyed by a conveyor belt

to the sifter 24 equipped with two superposed decks of sieves of a mesh size suitable to select those agglomdrates

within the size range desired. Oversized agglomerates

(coarse) may then be conveyed to a mill 30 where they are

reduced in size and then recycled to the sifter* 24. Under-

sized particles (fines) recovered from the sifter are reintroduced into the reactor 12. Quite unexpectedly, it has been found, that the "protein" quality of the agglomerated gluten obtained by

the methods of this invention, such as the foregoing, as compared with the quality of the powdered gluten starting

material is unimpaired and substantially unchanged so that,

in this important respect, it performs in a normal manner

when used in the manufacture, for instance, of yeast-leavened bakery products. This is confirmed by the comparative tests

detailed in Examples hereinafter. At the same time, the

functionality,'and hence the utility of the agglomerated

gluten in such applications is enhanced because of the

improved dispersibility and resistance to particle

coalescence following dispersion, i.e. dispersion stability. The agglomerated gluten of this invention, as

discussed in detail below, has a characteristic structure, 427.367

27, 364 P1 and a combination of desirable physical properties, which

serve to distinguish it from gluten presently available. Structure

Individual gluten agglomerates are composed

of a multiplicity, typically between about 3 and about of gluten particles bonded together in a random array to

give a coarse, irregularly-shaped structure of marked

porosity and with a surface area that is relatively large in relation to its bulk. The characteristic structure of

the agglomerated gluten, and the contrast with powdered

gluten are shown in the photomicrographs of Figures 3 and 4 in the accompanying drawings. Figure 3 is a photo- micrograph of a typical sample of the agglomerated gluten

photographed at a magnification of 40x. It shows clearly

the random aggregation of individual gluten particles,

into coherent irregularly-shaped structures. Figure

is a photomicrograph, for comparative purposes, of commercially available powdered gluten, at the same

magnification. This clearly shows that in contrast to

the agglomerated gluten, the particles of gluten powder are inherently separate and detached and individually of

a relatively regular shape with a low surface area relative

to the bulk thereof.

Properties

A. Size The size of the agglomerated gluten of this

invention as recovered from the process varies, though usually a major proportion, preferably more than 90%, of the

agglomerates remain on a 100 (or a lower number) mesh sieve

(all sieve sizes quoted herein r-fer to U.S. standard sieve 1% 427.367

27364 171 sizes) and are of a size in excess of 149 microns. In contrast, 90% of the particles in powdered gluten usually

pass through the same sieve size. The size of the agglomerates. is thought to be

an important factor in securing the desired characteristics

of the product.. Thus, when the agglomerates are ground so that they pass through a 100 mesh sieve, the' product does not have the desired characteristics in respect of, for

instance, the ability to quickly and readily disperse in. water without vigorous agitation to form a relatively

stable dispersion. Thus, it is considered important for the bulk of the agglomerated gluten to be of a size such

that it will remain on a sieve of a 100 mesh or less, or in

other words is greater in size than 149 microns, and this is normally obtained with the preferred method described above under varying operating conditions. Individual particles of

such size are easily discernible to the naked eye, whereas

particles of powdered gluten are not. Figure 5 illustrates the results of sieve

analyses upon a typical sample of agglomerated gluten

made in accordance with the present invention and, for

comparative purposes, a typical sample of powdered gluten,

and a typical sample of a commercially available product comprising powdered gluten coated with 20% by weight

monoglyceride (treated gluten). The desired series of sieves were stacked in their respective order in the series,

with the finest mesh size at the bottom. A 100 gin. sample of the material to be tested was placed on the upper sieve,

and the sieves placed in a Ro-Tap Sieve Shaker for minutes. The material on each sieve was then weighed and

the weight reported as a percentage of the total weight 427.367

27, 364/71 of material accounted for on the sieves and in the pan under

the finest mesh size. Referring to the Figure, curve A represents the sieve'analysis of the aqqlomerated qluten,

curve B represents the sieve analysis of the powdered gluten, while curve C represents the screen-analysis of the treated gluten. Essentially, these curves show the particle size distribution in the agglomerated gluten with

the major proportion of a size in excess of 149 microns, in comparison with that of powdered gluten and treated gluten in which the bulk of the individual particles are

of a size less than 149 microns.

B. Bulk Density

The irregular shape and bulky nature of the agglomerated gluten is reflected in the bulk density thereof

which is lower than the bulk density of powdered gluten, as determined by the following procedure:

The apparatus used was a Scott Volumeter

(available from the Fisher Scientific Company). It comprised a large brass funnel with a metal screen, and

a smaller funnel with a straight stem to direct the sifted gluten into a baffle box. This box had a series of glass

baffle plates which regulated the fall of the gluten. A

funnel at the bottom collected the gluten and directed it

into a cubic inch receiver. This was a brass box with a capacity ofexactly one cubic inch, and was supplied with

a counterpoised weight. The gluten, sifted at the top, was baffled in its fall so that it actually entered the

cubic inch receiver at the bottom under a constant head, which ensured the recaiver being packed in the same manner each time. The receiver and contents were weighed and the

-18 42 7.367

27, 36 4 F weight of the gluten in the receiver obtained. The results

(bulk density) were expressed in grams per cubic centimetre

A typical sample of agqlomerated gluten with

92% of a particle size in excess of 149 microns, had a with a bulk bulk density of.36 gm./cc/. which contrasted

density of .42 gm./cc. for powdered gluten.

C. Flowability The enhanced flowability of the agglomerated as a gluten compared with powdered gluten as well the gluten commercially available gluten product wherein (treated is coated with 20% by weight of a monoglyceride in the gluten) to improve functionality was demonstrated

following way: 800 Gms. of each product in turn were placed following in a standard 60 degree powder funnel of the dimensions: 150 m.m.

Overall 160 m.nm.

Stem height 15 m.m.

Stem diameter.. 40 m.m.

the funnel A stopper was fitted into the lower end of material. The stem to prevent premature release of the require. for the stopper was then removed, and the time reported as entire sample to discharge from the funnel

the flowability rate in seconds. The results are

tabulated below: 19 427.367

27, 36 4 7 Table I Product Flowahility (sOCS.)

Agglomerated gluten Average particle size->250 12

powdered gluten Would not flow

Treated gluten 26

It is apparent from the above data that the

agglomerated gluten has a markedly superior flowability

compared to both prior art gluten products. The free-flowing

character of the agglomerated gluten is reflected in the ease with which it can be removed from the package and poured without plugging or dusting. D. Wettability Dispersibility

The enhanced wettability and dispersibility of

the agglomerated gluten in contrast with powdered gluten

as well as powdered gluten treated with 20% by weight of a monoglyceride can be demonstrated as follows:

A 400 ml. low form Griffin beaker was filled

to approximately one inch from the top with water at 200C. and a teaspoonful of each of the three materials in turn

carefully placed on the surface of the water. The

dispersal time was reported as the number of seconds

required for all of the material to sink below the surface of the water:.

Agglomerated Gluten When the teaspoonful of a typical sample of

agglomerated gluten was placed on the surface of the

water, it floated thereon only transiently and

progressive sinking occurred within a second or so.

The dispersal time was 2 seconds. As the material .20 427.367

2, 364 sank toward the bottom of the beaker it disintegrated

and dispersed without the need for even gentle stirring.

In a short space of time (7 seconds), the bulk of the

gluten was resting on the bottom of the beaker; gentle

stirring recreated a -uniform dispersion free from lumps.

(ii) Powdered Gluten

When the test was applied to this material, the bulk of it floated upon the surface of the water, and

when the contents of the beaker were permitted to

stand without stirring, the powder formed a lumpy,

doughball-like, mass. The dispersal time could not be ascertained since the bulk of the material never sank below the surface. On hand stirring the contents of the beaker, an intractabl.e, elastic mass of

hydrated gluten was formed instead of the powder dispersing to form a uniform slurry. In fact, even vigorous agitation was not effective in breaking up the lumps. (iii) Treated Powdered Gluten

When the test was applied to this material, the bulk of it initially floated upon the surface

and only slowly sank below. The dispersibility time was 3 hours. This could be shortened by vigorously

agitating the material when it sank and disintegrated.

to form a relatively stable dispersion.

The contrast between the three sorts of gluten

product (i to iii) in respect of wettability and dispers-

ibility is illustrated in Figures 6 and 7. Figure 6 shows the result, after a given time in seconds as indicated on the stopclock, of placing a spoonful of the powdered 2- 427.367

27, 36 4 gluten and a spoonful of the agglomerated gluten on the surface of water in two beakers (A and B rcsnectively) with gentle stirring of the contents at the same speed.

Corresponding Figure 7 shows the comparable result for

treated powdered gluten and the agglomerated gluten (A and

B respectively). As can be seen,in both instances,:almost all the agglomerated gluten has sunk beneath the surface

and, in moving toward the bottom of the beakers, has dis- integrated and dispersed to form a relatively uniform

slurry. In contrast thereto, the bulk of both the

untreated and treated powdered gluten have remained floating on the surface of the water.

E. Dispersion Stability The stability, i.e. the resistance of

individual particles in an aqueous dispersion of the

agglomerated gluten to coalesce was determined by placing 0 gms. of the material in 100 ml. distilled water at 20 C.,

while stirring continuously with a mechanical stirrer

operating at 350 r.p.m. For comparison, dispersions were

formed in an identical manner with the same amount of

untreated powdered gluten and treated powdered gluten

(coated with 20% by weight monoglyceride). Following

formation, the dispersions were allowed to stand for 24

hours prior to evaluating the stability of the dispersion

as reflected in the extent to which individual particles

stayed separated and distinct. Both the agglomerated

gluten and the treated powdered gluten exhibited little

coalescence between individual particles and remained in the form of a fairly uniform dispersion. This contrasted 22 427.367

27,364 P1 with the ordinary powdered gluten in which the particles

had flocked together to give a more or less unified and

intractable mass of hydrated gluten.

F. Porosity

Reference has been made herein to the porous

nature of the individual gluten agglomerates. A bulk mass

of the agglomerates is likewise porous on account both of the porous nature of the agglomerates themselves, and

bridging between the agglomerates which prevents a clbsely packed relationship and,'gives rise to many interstitial

spaces. The superior porosity of the agglomerated gluten

compared to ordinary'powdered gluten is demonstrated in

the following test:

A glass tube 150 mm. long and 16 mm. internal.

diameter was packed with gluten to'a depth of 100 mm.; the gluten was tapped down firmly. With the tube in the

vertical position, 1 ml. of water was pipetted into the tube. The depth of penetration of the water, in mm., into

the sample after 30 seconds was noted. With a typical

sample of agglomerated gluten, the water penetrated 25 mm.

in contrast to the 1 mm. penetration achieved in ordinary powdered gluten. This comparative test clearly demonstrates

the superior porosity of the agglomerated gluten.

H. Moisture-Content

The residual moisture content in the agglomerated

gluten product is important in ensuring optimum dispersion

of the agglomerated gluten in water; we have found that

an agglomerated gluten with a moisture content in excess of 10% is less readily dispersed in water than agglomerated .3 427.367

27,364 11

gluten with a lower moisture content. Proferably, the

residual moisture content is between 6 and for then

the agglomerated gluten often disperses spontaneously no need simply on addition to water and usually there is typically for even gentle stirring. Ordinary powdered gluten 6%. has a residual moisture content of between 4 and A still further characteristic of the agqlomerated are gluten is that its flavor and baking characteristics treatment, not noticeably impaired by the agglomerating Examples as will be demonstrated by the comparative tests in hereinafter. Summarising the characteristic and advantageous

propcrtion or tiw .o ll(IimeraLed jlulen as co)mL)arod wi'th formeris ordinary gluten powder, the functionality of the and dispersed markedly superior because it is readily wetted i.e. reduced in water to form a relatively stable dispersion, ideally suited tendency to coalesce. For these reasons, it is bakery products. for use in the manufacture of yeast-leavened and dark The most common of such products are of course white breads, rolls and cakes. The agglomerated gluten is of and rolls particular importance in the manufacture of bread involving by the so-called continuous dough-making processes brew, where' the initial formation of a liquid preferment or to the brew the agglomerated gluten may be added directly and without any difficulties associated with the wetting and maintained dispersing thereof, or the formation of a foam, until final in a dispersed state simply with gent!.2 agitation

dough development takes place. of the While up to about 10 percent by flour weight in agglomerated gluten of this invention may be incorporated Z4. -427.367

27, 36 4 I71 of the the doughs with resulting improvements in-the quality ultimate bakery products, best results with least expense content of Are generally achieved at an agglomerated gluten between 2 arnd 4 percent by flour weight. The invention is further described in the following

Examples which, being illustrative are not intended to limit may the scope of the invention, except as such limitations appear in the appended-claims. Example 1

Preparation of Agglomerated Gluten

The apparatus assembly described with reference used in~ a to Figure 2 of the accompanying drawings was typical run to process a powdered gluten commercially Thunder Bay,. available from Industrial Grain Products Limited, reactor at a Ontario, Canada. the gluten was fed into the bed rate of 600 lbs. per hour and formed into a fluidized the diffuser by admitting heated air to the chamber through in the form of plate at a constant rate of 40 f.p.m. Water into the droplets of a size 10 to 100 microns was sprayed each delivering fluidized bed through ten, two-fluid nozzles, 35 ps.i.g., i.g.p.h.water, utilizing air at a pressure of

as the atomizing agent. The temperature of the air entering the 0 about 115 C. and plenum chamber below the diffuser plate was chamber was the tempera ture of the gluten in the treatment 0 about 46 C. The bulk of the gluten recovered from the above

process was in the form of dry, coarse, irregularly-shaped size greater than agglomerates at least 90% of which were of a 149 microns. 1S'427.367

27,364171 That the agglomerated gluten so-obtained retains powdered the original chemical properties of the original gluten and differs therefrom only in certain advantageous given physical properties is demohstrated by the results properties in the following table which compares relevant

of the agglomerated gluten with those of the initial powdered gluten.

427.367

27,36 4/71 Table II.

Comoarisons of Properties of Agglomerated Gluten and Powdered Gluten

Property Agglomerated Powdered

Moisture 8

Protein dry basis 80

Ash dry basis 0.8 0.8

Colour Croam Off-white

Bulk Density 0.36 0.42

Flowability (seconds)* 15 Does not flow

Aqueous Dispersion Uniform Lumpy; imposs- ible to disperse

Dispersion Stability Can be resus-- pended with slight stirring after standing for 24 hours.

Mesh Analyses* on 25 2.2--

on 40 30.2

on 60 37.4

on 80 19.2 1.1

on 100 3.2 30.5

on 120 2.8 37.9

on 140 2.2 10.9

on 170 1.0 8.2

Son 200 1.8 10.1

thru 200 1.3

Tests conducted as described hereinbefore. That the protein quality of the agglomerated

gluten is unimpaired relative to the initial powdered gluten was shown by comparisons of Brabender farinographs 2L 427.367

27, 36 41 of flour containing the same amount of agglomerated gluten

of this Example, and the powdered gluten as well as, for

illustrative purposes; a treated (20% by weight monoglyceride)

powdered gluten of the prio- art.

The procedure followed was a standard one of the Dough Testing American Association of Cereal Chemists, Physical Methods 54 21, Constant Flour Weight Procedure (large bowl)

as published in Cereal Laboratory Methods, 7th Edition, AACC (1962). In each instance, 8% by weight of the given wheat gluten was admixed with 92% by weight of untreated soft on the flour. For control purposes, a farinograph was run soft wheat flour alone.

The results are summarised in Table III below: TABLE III

Product Property A B C D Absorption 52*5 57.1 Arrival Time (min.) 1 1.3 1.5 1.1 Peak Time (min.) 1.5 2.5 3.5 Departure Time (min. 4 17.0 17.5 16.9 Stability (min.) 3 15.7 16.0 18.0 M.T.I. 35 20 10 Improvement cf. A. =100% Absorption 8.76 8.19 4.95 Arrival Time 30.00 50.00 10.00 Peak Time 66.66 +133.33 Departure Time +325.00 +337.50 +322.50 Stability +423.33 +433.33 +500.00 M.T.I. 42.86 71.43 14.29

A E control (no gluten). B E agglomerated gluten. C E Untreated powdered gluten. D 2 Treated gluten.

427.3G 7

27, 36411 INTERPRETATION AND SIGNIFICANCE OF DATA Farinograph The farinograph is an instrument widely used in the flour industry to determine the basic mixing and rheological

characteristics'of a flour-Vater dough system. It follows that if a substance modifies the characteristics of a dough, this

modification will be reflected in the farinogram.

In the farinograph, flour, or flour-gluten mixture and water are mixed and the viscosity of the dough during mixing is measured and recorded as a farinogram. The various stages of viscosity have been found to be related to actual

bakery performance of the flour. The Absorption describes the amount of water needed to arrive-at a given optimum viscosity. This optimum viscosity (consistency) is referred to as. 500 Brabender Units

All other readings of the farinogram are based on this correct

absorption. A change of more than 1% based on the flour is considered significant. An increase rather than a decrease is

generally sought.. The Arrival Time is defined as the time at which the farinogram curve first touches the 500 B.U. line. This point reflects the speed with which a flour hydrates and develops viscosity and elasticity. It is sometimes referred to as the hydration time. A rapid hydration or short arrival' time is recognized to be beneficial. A change of one minute

or more is considered as significant. The Peak Time is defined as the time when maximum viscosity is attained. A lengthening of the peak time is generally recognized as beneficial. A shift of one or more minutes is significant. The Departure Time is defined as the time when the

"29 427.367

27,364/71 viscosity curve registers less thani 500 B.U. following the

peak. This point is indicative of the breakdown of the dough under the mechanical puni shment of mixing. It is general ly

felt that the longer departure times are beneficial.

Significance-is accorded to a change of two minutes or more.

It should be noted that excessively long departure times (over

minutes) may be just as damaging as extremely short ones.

The Stability is de.fined as the difference in time

between the departure and arrival time. The stability is a

measure of the tolerance of a dough toward mechanical.

punishment. It measures the time during which the consistency.

of a dough being mixed remains relatively constant. Changes

in a dough which increase stability are beneficial. As in

the case of departure time, excessively long stability can be damaging since it will be difficult for a baker to control

the machining of his dough to achieve optimum conditions. An

increase of three minutes is recognized as significant.

The or Mixing Tolerance Index is defined as

the decrease in viscosity of a dough S minutes after

the peak time. A dough which breaks down more slowly will

therefore have a lower this is recognized as beneficia

A change of 10 B.U. or more is considered significant.

The Percent Improvement data should be evaluated with

great care. The farinogram presents a composite of several

characteristics and it must be evaluated in this way to yield a meaningful picture. The significance of the percent improve-

ment of individual characteristics should not be stressed under

conditions where a composite of characteristics is more

meaningful than individual characteristics. As interpreted,

it is clear from Table III that the protein quality of the -427.367

27,364171 non-coalescing agglomerated gluten is in no way inferior to that of the powdered gluten, treated or untreated. Moreover, it will be noted that the agglomerated gluten has the highest water absorption which indicates the amount of water, based on flour weight, which is necessary to obtain a uniform dough consistency. This is an important factor, especially in the baking industry, for such an increase permits the baker to increase his yield from a given weight of flour so improving the cost effeciency. Further evidence as to the unimpaired protein quality of the agglomerated gluten is provided by Brabender extensographs of compositions containing a given amount of- the agglomerated gluten of this Example, ordinary powdered gluten and powdered gluten treated with 20% by weight of a monoglyceride. These tests were conducted under standard conditions on a Brabender extensograph Which is a well-known device for measuring and recording the extensibility and resistance to extension of flour doughs. In this instance, the doughs were derived from the following compositions:

Table IV Dough Composition Gluten Wheat Starch* Water (gms.) (gms.) (cc.) A 42.9 232.5 210.6 B 43.8 23".3 209.4 C 52.4 221.8 211.8 The wheat starch used was Supergell,

commercially available from Industrial

Grain Products Limited, Thunder Bay,

Ontario, Canada. ~427.367

27,36 4 171 A Agglomerated Gluten

B Untreated Powdered Gluten

C Treated Powdered, Gluten

The results of the extensograph analyses are

summarised in the Table below- Table V

Resistance to Extensibility Extension BU (Time Units) 1 hour 1 2 hours 1 hour 2 hours

723 1009 4.52 3.65

750 960 4.27 3.75

526 807 4.58 4.20

It will be apparent upon comparison of the

foregoing results that the quality of the agglomerated gluten

has not been deletoriously affected in the process of making

it from .the gluten powder starting material.

42 7.367

27,364 171 Examnle 2 Four sample s of agglomerated gluten were prepared following the basic procedure of Example 1 but employing, in the fou r runs, different operating conditions

as summarised in the Table below:

Table VI Condition Run #1 Run #2 Run #3 Run #4 Airflow rate (s.c.f.m./ft.2 60 60 40 Temperature of inlet air (oC) 137 137- 137 115 Temperature of gluten (fluidized bed) 51 57 60 46 Gluten feed rate (lb. per hour) 100 75 1350 1300 Gluten particle size -18 +80 -18 +80 -16 +100 -16 +100 Water feed rate (gal. per hour) 4 4 13 Atomizing pressure 50 50 35

Various properties of the four samples of agglomerated gluten are summarised in the Table below:

42 7.3 67

27. 36 4 171 Table VII Property Run #1 Run #2 Run #3 Run #4

Moisture -4.5 5.0 5.0

Protein (dry basis) 80.5 80.7 80.7

Ash 0.8 0.8 0.8 0.8 (dry hasis)_ Colour Cream Cream Cream Cream Bulk Density .40 .40 .40 .36 Flowability (seconds) 13 14 13

Dispersibility Good: Good: Good: Excellen needs needs needs spontan gentle gentle gentle eous stirring stirring stirring

Dispersion Stability Can be resuspended with slight stirrin after settling for 24 hours Vitality Good Fair Good Good

Sieve Analyses on 25 Not tested 2.2

on 40 5.9 30.2

on 60 32.0 37.4

on 80 42.2 19.2

on 100 6.2 3.2

on 120 4.5 2.8

on 140 3.2 2.2 on 170 1.8

on 200 4.2 1.8

thru' -200

Example 3

The superior functionality of the agglomerated gluten product of this invention in its application to the bakin 427.367

27..364I71 industry in comparison with untreated powdered gluten and

treated powdered gluten was demonstrated in a sponge dough

bread-making process. The agglomerated gluten used was that

from Example 1. The treated powdered gluten comprised

powdered gluten coated with 20% monoglyceryl stearate. For

control purposes, the process was repeated with no added gluten.

Formulation

Ingredients Content .is. Sponge Dough

Flour* 240 160

Sugar 12

Salt 8

Water 144 98

Yeast 8

Yeast Food** 13.

Milk Po~wder 12

Shortening 12

Gluten*** of flour) 4

SThe flour used was a 50-50 blen~d of hard and soft wheat flours (moisture content of 13.5%,

.46% ash, 10.2% protein). The yeast food was of the Arkady Double

Strength type.

**The agglomerated gluten product, the un-

.reated and treated powdered glutens were

added to the sponge at levels of 4% by weight

in each case, based on the weight of the flour. Procedure

The sponge was made by mixing the sponge ingredients

in the McDuffee bowl of a Hobart mixer and mixed for one. I 35 427,367

27, 36 4 71 minute at No. 1 speed, using a 3 spindle fork. The bowl was

then scraped down and the sponge again mixed for four minutes

at No. 2 speed. It was noted that during the mixing the

agglomerated gluten was the most easily dispersed in the water.

The sponge was removed from the bowl at this point and-set 0 aside to ferment for 4hours at 27 C. To prepare the ultimate

test bread doughs the dough ingredients were added to the

sponge in a stainless steel Hobart mixing bowl and the mass mixed at No. 3 speed for 12 minutes using a dough hook. This

dough was then rested for 15 minutes and scaled into 162g.. portions which were hand rolled, sheeted and molded. The

molded dough pieces were panned, proofed for 10 minutes at

and 85 percent relative humidity. The proofed dough was

then baked at 2180C. for 25 minutes and the resulting bre ad allowed to cool.

Results one hour after baking, the volume of each loaf

was measured by rapeseed displacement. The loaves were

judged the following day. Both external and internal

characteristics were observed and rated according to the

standard scoring procedure of the American Institute of Baking. The total score-(maximum of 100 for a perfect loaf)

is the sum of the scores of the internal and external

characteristics. Specific volume was calculated by dividing

bread volumein cubic centimeters by dough weight in grams. The results are reported in the table below.

4 2 7. 3'67.

27,364 17 Table VIII

Gluten Type Level Specific Total by flou- Volume Bread weight) Score

Agglomerated gluten Example #1 4 6.4 91

Untreated powdered gluten 4 6.4

Treated powdered gluten 4 6.2 89

Control No gluten 0 5.6 83

Conclusions It is apparent from the results quoted that

the agglomerated gluten gave the best baking result, and,

that, in comparison with powdered gluten and the treated-

gluten, the agglomerated gluten had not lost any vitality

in the process for preparing it. Example.4

A similar evaluation to that of Example 3.

was dnducted using a continuous bread piocess involving

"Amnflow" continuous dough making equipment manufactured

by the Bakery Division, American Machine and Foundry

Corporation. The machine used was a pilot plant Amflow

model which was a smaller scale version, specially adapted for experimental investigation, of the larger commercial machine, and consumed 100 lbs. flour per hour to produce

180 lbs. dough per hour. The same three glutens were

employed as in the preceding Example, and the formulation

is shown in the Table below.

427.367

27,364 1' Table IX

Continuous Dough Formulation Content (b) Ingredient arew Dough 40 100 Flour

57 67 Water 3 3 Yeast. 0.08 0.08 Ammonium sulfate

0.5 7 Sugar 0.2 2.2 Salt 3 3 Gluten Milk Calcium Acid Phosphate 0.4

Calcium Propionate 0.1

Atmul 0.1

Shortening -3.3

Potassium Bromate 60 p.p.m.

Potassium lodate 10 p.p.m. 3. Similar to the flour used in Example Procedure The brew which contained 40% of the total flour

was made by mixing the various brew ingredients and then 0 setting the mixture at 80 F. The incorporation of the with untreated powdered gluten was achieved by preblending at this the flour. The brew was allowed to ferment During this temperature for 2 hours without agitation. for developing period, hydration and relaxation (necessary

gluten functionality) occurred. The remainder of the flour, and gluten and water, yeast, ammonium sulfate, sugar, salt usual manner at the other ingredients were combined in the identical to the incorporator. Processing conditions were 38 427.367 those usually employed. 27, 364 17 The developed doughs were extruded directly from the high-speed developer into tared pans, proofed for 70 minutes and baked for 18 minuLes at 2181C. Observation. It was noted that the agglomerated gluten was more readily wetted and became more fully hydrated and relaxed than the monoglyceride coated gluten. It was noted that the dry gluten added to the brew had an effect on the behaviour of this brew. Both the powdered vital wheat gluten and the agglomerated vital wheat gluten lowered the foaming properties of the fermenting brew. This was a distinct advantage since excessive foaming leads to overflow of the brew from the preparation and storage tanks, a recognised problem in continuous bakery operations. The control brew which did not contain added gluten had a marked tendency to foam. And, not surprisingly, this'tndency to foam was even more marked with the brew which contained the monoglyceride coated gluten. The amount of foaming was measured by determining the volume increase of the brew. With no gluten, the brew volume increased 70% and the brew collapsed and started to foam again. With gluten present (both the powdered and agglomerated), brew volume increased only 30%; with the monoglyceride coated gluten, the brew volume increased 100%. Results The results are summarised in Table X below:

427.367

2 ~36 4171

0 -4 U) co 00 If

f

44 n a n C!if a, 4 i)i tn if

120

0. -4

-4 =4 -4 I4.) *44U U)H ,a4J109 04 0i-,4 r 0 0 A 9; 0-414 U0 -H 4 o4) 0 (1) .0 d 4.1 >4~ 04 4J 14 r. 4 ~4) 'X 0J 0 0 X 4-4 0.G 04) .0 4 4) 4-4 4-I *d 44 an 0 44I -4 X 4-4 0Ox O 0 "-4 r- W4 0) 14 cnrxD44.)Oa

0zU) U)0

an 4) H- ciN

0

4-4 00C 0 41 144

C: '0 -4 Wn 0 4 .D Oa [4 OH

42 7.367

Conclusions 27?1" 3 64171 .All the bread obtained was of good quality, but that obtained using the agglomerated gluten, was noticeably the

best having the highest vol-ume, strongest sidewalls, a fine, uniform grain and a soft, velvety texture.

Example A laboratory scale baking procedure involving the

use of a preferment or brew was conducted to further confirm

the improving effect of the agglomerated gluten,(Eg. 2, Run according to this invention at a level of 8% by weight compared to the same content of untreated powdered gluten.

Table XI Formulation (for 1 loaf).

Content (gins.) "Ingredient Brew Dough Flour *75 225 Water .186

Yeast 9 Sugar Salt

Shortening

Salt

Gluten 24 Potassium bromate *Soft wheat flour (moist-ure content of'12.5%, 0.5% ash, 8.5% protein) The brew, which contained 25% of the total flour, was made by mixing the various brew ingredients with the formula

water at 800 F. using relatively gentle agitation to achieve

a uniform dispersion. The brew was then allowed to ferment at this temperature for 2 hours in a closed container without 41 427.367

27, 36 4 agitation. To prepare the ultimate bread dough, theremainder

of the flour, sugar, salt, shortening and bromate were added

to the brew in a stainless-steel Hobart mixing bowl and the speed,.followed by 2 1 mixture stirred for 30 seconds on-No. 1

minutes on No. 2 speed. The dough was then given a floor time into 500 g. of 30 minutes at 40*C., after which it was scaled 0 45 C..for 60 minutes at portions, molded, panned and proofed at dough was then bakec percent relative humidity. The proofed bread allowed to co( at 218 C. for 22 minutes and the resulting 0

Observations

In making the brews, it was noted that numerous clumps

formed when-using the untreated powdered gluten. However

upon vigorous agitation, most of these clumps tended to disappear though some remained and these tended to be difficult to hydrate.

Only very slight foaming was noticed when using, the

agglomerated gluten. With the untreated powdered gluten

the foaming was more marked while with a control run

using no gluten (99 lbs. flour in brew) the foaming was

moderately severe. Results Table XII

Run'No. Type of Specific Total Gluten Volume Bread Score (cc./gm.

1 Agglomerated 4.3 gluten M8)

2 Untreated potildered gluten 3.9

3 Control (no gluten) 3.2

1, 42 427,367 ohclusions 27, 36 4 71 Using this soft, very low protein flour only the gglomerated gluten gave bread that would be acceptable ommercially. It was noticed that the reproducibility of loaf olume and quality was much superior for loaves prepared sing agglomerated gluten as compared to loaves prepared with rdinary powdered gluten; this reflects the better ispersibility and non-coalescence of the agglomerated gluten. Example 6

The sponge dough procedure of Example 3 is

epeated using the agglomerated gluten of Run Example 2.,

ncorporated in the dough at levels of 1, 3, 5, 7 and 10 percent y weight, based on the flour weight. In all cases the

esulting bread was of good quality and symmetry with fine rain texture and body. As demonstrated by the foregoing Examples 3 to 6, tieagglomerated gluten product of this invention is well

aited for application in the baking industry offering distinct ad significant advantages over the ordinary powdered gluten

ad coated gluten products presently used. It is of especial value for use in continuous

Dugh-making processes for it can be readily and conveniently

corporated in the liquid fermentation brew so that the

Luten has time to hydrate and relax which is needed for the

avelopment-of its functionality in the dough system. Although

a the foregoing description reference has been made to the 3e of the agglomerated gluten in the manufacture of bread,

t will be understood that the product may be used in the anufacture of other products, such, for example, as pasta 4 4.27.367 aterials. I

27,364i' illustrated Although the present invention has been will be understood by reference to embodiments thereof, it be employed without that modifications and variations may of the invention, as those departing from the spirit and scope Such modifications skilled in the art will readily understand. to be within the and variations are therefore considered claims. purview and scope of the appended

44 427,367

The 27,364/71 The claims defining the invention are as follows:-

1. A dry vital wheat gluten product in the form of coarse, porous, irregularly-shaped agglomerates composed of a multiplicity of individuaU gluten particles adhered together in a random form and array, the major proportion of the agglomerates having a particle size exceeding 149 microns, the gluten product being further characterised by the ease with which it can be dispersed in neutral aqueous dispersion (about pH 4 to about pH 8) by simply stirring to form a relatively stable dispersion in such a medium. 2. A gluten product as claimed in claim 1, wherein at least 90% of the agglomerates have a particle size in excess of 149 microns, and a residual moisture content of less than about 3. A gluten product as claimed inclaim 1 or 2, wherein the gluten has a residual moisture content of between about 6 and about 4. A gluten product-as claimed in any one of claims 1 to 3, wherein the gluten has a residual mc.isture content of. between about 6 and about 8%. A gluten product as claimed in any one of claims 1 to 3, wherein the gluten has a bulk density of less than 0.40 gms./cc. 6. A gluten product as. claimed in claim 1 substantially as described with particular reference to Examples 1 and 2 herein. 7. A process for improvring the functionality of vital wheat gluten particles without denaturing the gluten, comprising exposing the individual gluten particles in a treatment zone to the action of/efte-a P' q e ,nV;,-1ti t agent so as to render

A* 427.367

Claims (1)

1. 2 7, 364/71 the surfaces thereof sticky, commingling the superficially agglutinated particles while dispersed in such a treatment

   zone thereby causing them to adhere together in.the form of coarse, porous agglomerates-of random shape and form with a majority of a size greater than 149 microns, and drying

   the agglomerates to adjust the total residual moisture

   content to less than about

   8. A process as claimed in claim 7, wherein the gluten particles are superficially agglutinated with the wtti.ng

   agent, agglomerated and dried almost instantaneously in a

   single, treatment zone. 9. A process as claimed in claim 7 or 8, which comprise the following steps:

   forming the powdered gluten into a fluidizec

   bed; maintaining the bed in a particulate fluidized state by passing a fluidizing gas,

   such as compressed air, upwardly through the

   bed; Ic) discharging/a woting agent in atomized

   form directly into the particulate, fluidize

   bed between the top and the bottom thereof

   so as to agglutinate the surfaces of the

   particles which are commingled, by the

   gentle agitation of particles in the bed,

   to an extent sufficient to cause such particles on contact with adjacent particles

   to adhere together in the form of moist,

   irregularly-shaped agglomerates; and drying the aglomerates by means of the

   4 6 427.367

   2 7!36 4 P' fluidizing gas to a residual moisture

   content of less than about A process as claimed in any one of claims 7 to 9, wherein th/etsagent -Ls water.

   11. A process as claimed in claim 7, substantially as' described with particular reference to Examples 1 and 2 herein.

   12. A gluten product whenever prepared by a process

   as claimed in any one of claims 7 to 11. 13. A process of producing yeast-leavened bakery products, which comprises incorporating along with the

   standard dough ingredients including flour, shortening, sugar and salt prior to baking an effective amount up to.

   about 10% by flour-weight of an agglomerated gluten product in the form of coarse, porous, irregularly-shaped agglomdrates

   composed of a multiplicity of inidividual gluten particles

   adhered together in a random form and array, the major

   proportion of the agglomerates having a particle size exceeding

   149 microns, the gluten product being further characterised by the ease with which it can be dispersed in neutral aqueous

   dispersion (about pH 4 to about pH 8) by simply stirring to

   form a relatively stable dispersion in-such a medium. 14. A process as claimed in claim 13, wherein the gluten

   is incorporated in an amount of between 2 and 4% by weight.

   A process as claimed in claim 13 or 14, wherein at

   least 90% of the gluten agglomerates have a particle s ize in

   excess of 149 microns, and a residual moisture content of less

   than about 16. A process as claimed in any one of claims 13 to wherein the gluten has a residual moisture content of between

   about 6 and about 8%.

   41 427..*3 67

   27,36 471 17. A process of improving the quality of yeast-

   leavened bakery products substantially as described with

   particular reference to any one of Examples 3 to 6.

   18. Yeast-leavened bakery products whenever produced

   by a process as claimed in any one of claims 13 to 17. 19. Yeast-leavened doughs containing an effective

   amount up to about 10% by flour weight of an agglomerated

   gluten product in the form of coarse, porous, irregularly-

   shaped agglomerates composed of a multiplicity of individual gluten particles adhered together in a random form and array, the major proportion of the agglomerates having a particle

   size exceeding 149 microns, the gluten product being further characterized by the ease with which it can be dispersed in

   neutral aqueous dispersion (about pH 4 to about pH 8) by

   simply stirring to form a relatively stable dispersion in

   such a medium. Yeast-leavened doughs as claimed in claim 19

   containing between 2 and 4% by weight of the gluten.

   21. Yeast-leavened doughs as claimed in claim 19 or

   wherein at least 90% of the gluten agglomerates have a

   particle size in excess of 149 microns and a residual moisture

   content of less than about

   22. Yeast-leavened doughs as claimed in any one of claims

   19 to 21, wherein the gluten has a residual mositure content

   of between about 6 and about 8%.

   23. Yeast-leavened doughs as claimed in claim 19,

   substantially as described with particular reference to any

   one of Examples 3 to 6.

   24. In the baking of yeast-leavened doughs, the improve-

   ment which comprises incorporating in the dough prior to

   427,367

   27 364 171 baking the product of any one of claims 1 to 6 or 12.

   DATED this 5th day of April, 1971.

   THE OGILVIE FLOUR MILLS COMPANY, LIMITED

   Patent Attorneys for the Applicants F.B. RICE CO.

   42.~,367

   27 3 64Rit F1G.1. PROCESS-FL OW S fEET

   POWDERED3 VITAL WHEAT GLUTEN To 125 MICRONS

   TREATMENT WITH WETTING AGENT

   COMMINGLING AGGLUTINATED GLUTEN PARTICLES se UNDER DEFINED CONDITIONS cc

   POROUS AGGLOMERATED GLUTEN PREFERABLY 90%-149 MICRONS

   AGGLOMERATED GLUTEN DRIED BY HEATING-600C

   27.3 64171

   F16.2

   27.3 64 17'

   FIG3.

   FIG.4. Fi p

   200

   S LUI

   27,3 64 71 PERA DISTRIBUTION OF MATERIAL

   2 m

   oI C, rl

   M jE- C"

   C"

   CD

   27.3 64i71

   FIG.6.

   A B

   F/67.

   A B