Note: Descriptions are shown in the official language in which they were submitted.
1~7~2~
case 3309
DESCRIPTION
DIRECT EXPANDED, HIGH FAT, FARINACIOUS
PRODUCT AND PROCESS THEREOF
TECHNICAL FIELD
05 This invention relates to a process for directly
expanding a high oil, essentially farinaceous material
and a direct expanded, high fat, farinaceous product.
More particular this invention is concerned with
extruding a cereal flour-based dough having at leas-t
6% oil into direct expanded breakfast cereals, snack
items, pet foods or the like with good texture,
flavor and eating characteristics, consumable as is,
as well as in hot and cold liguids such as milk.
BACKGRo~ND ART
Extruding cereal products containing high
levels of oil have always been a problem. At low
levels, however, oils do no-t seem to interfer with
the cooker extrusion of flour doughs.
In cereal formulations containing mainly
farinaceous materials, the presence of high levels
of oil prevent the expansion of the product upon
exiting the extruder. Several attempts have been
made to extrude cereal products containing high
levels of oil. However, as the level of oil
approaches about 5~ very little success has been
achieved.
~æ'~7926
The following references disclose findings
~here cereals are extruded with various oils.
Mercier et al. in "Formation of Amylose-lipid
complexes by Twin Screw Extrusion Cooking of Manoic
05 Starch", Cereal Chemistry Vol. 57, at 4 (1980)
disclose that 2 to 4% neutral fat did not affect the
e~trusion of manoic starch.
Wiederman et al. in "The Influence of Recipe
Variations of Process Parameters and Product Quali-ty
Taking Flat Bread as an Example" Lecture, Werner &
Pfleiderer Food Extrusion Presentation, Stutgart,
Germany, Dec. 10, 1981 discloses that the introduc-
tion of sesame seeds (50% oil) into the extruder
feed increases the protein and oil content of the
mixture. The protein content raises energy absorp-
tion and extrusion pressure, but only to a minor
extent because the oil content acts as a lubricating
agent. On the other hand, the oil hinders the
formation of pores which causes the extrudate density
to rise and the degree of expansion to fall off
rapidly. ~t 10% sesame seed, the oil contained
therein (5%) starts to be pressed out resulting in
unstable extrusion conditions.
Certain formula components can increase the
extrudability of high fat feedstocks. For instance
U.S. Patent No. 3,~23,885 to Hamdy et al. discloses
a process for extruding a proteinaceous material
containiny up to 5% fat by the addition of small
amounts of finely divided ~-cellulose to the extruder.
Hamdy et al. also teaches that substantially more
than about 5% by weight of fat cannot be satisfac-
torily incorporated by the method of the invention.
This reference claims that such a formula was not
satisfactorily extrudable previous to the invention.
. .
~ ~ ~t7~ z ~ -
- 3 -
It was further reported by Wiedmann et al. that
when feedstock containing whole milk powder is
extruded the influence of fat is an overriding
factor. Consequently, energy and extrusion pressure
05 all of gently and the degree of expansion at 20%
whole milk powder (5.6% fat in the product based on
28% milk fat levels) falls by approximately half.
The fat content generated pulsating extrusion
conditions with many plasticizing zones, even at low
concentration, so that normally 3-4% whole milk
powder (equaling about 1.2% fat) could not be exceeded.
Split plasticizing zones interspersed with stabilizing
conveying makes it possible to add 20% whole milk
powder.
Conway in "Extrusion Cooking of Cereals and
Soybean -Part I." Food Prod. Dev. 5 27 (1971)
reported that for the cooker expansion of a formula
with an oil level of about 5%, a starch content o
60% to 70% is needed. When more -than 5% oil is
present, either as added oil or oil in the meal
fraction the level of expansion will be reduced or
prevented.
U.S. Pat. No. 4,325,976 by Harrow et al. discloses
extruding rice using a conventional low pressure
pasta~type extruder. The extruder composition
con-tained a powdered fat. The powdered fat was
prepared by spray drying an emulsion of fat and a
carrier such as malto-dextrin. The composition had
up to 10% spray-dried fat, equivalent to 7~O pure
fat. The reason for using powdered fat was to
eliminate the effect of extruding fat on the rate of
dehyclration. The temperature of the extrusion was
not disclosed, however, the resulting product was
not expanded. It is known in the art, nevertheless,
:~4792~
that pas-ta extrusion is a cold formillg procedure
where neither gelatinization nor expansion ta~e
place.
Mercier et al. cited supra; U.S. Pat. No.
05 4,369,195 to Nelson et al.; and Mercier et al. in
"EfEect of Extrusion Cooking on Potato Starch Using
a Twin Screw Ex-truder" disclose -that in the typical
low fa-t, high temperature (250 -to 400F) cooker
extruder process for cereals, the starch granules
are disorganized into a dex-trinous, amorphous structure.
The dextrinization can be demons-trated by X-ray
diffraction and by the fact -tha-t extruded s-tarch can
become almost completely water soluble. The high
water affini-ty and solubili-ty of direc-t expanded,
high -temperature, shear and pressure cooked starchy
materials can be detrimental in certain applications,
where a wa-ter resistant shape and texture stable
produc-t is desire.
To date, no one has developed an accep-table,
high oil (6% or above~ direct expanded oat or other
cereal with acceptable texture and which can be
consumed in hot as well as cold fluids such as milk.
As an example, 100% oat cereals which cQntain abou-t
7% oil have been limi-ted to unexpanded gruel-like
cooked products. Expanded oat formulae could only
be produced with oats as a partial ingredient.
~79~
SUMMARY OF THE INVENTION
The present invention is concerned with a
direct expanded, high oil, farinacious product and
a process for preparing a direct expanded farinaceous
05 product having high oil content, comprising the steps
of: feeding a mixture of a farinaceous material
having at least 6~ oil, and water in amounts effective
to prepare a dough into an extruder; incorporating a
gas into the dough to provide an aerated cell structure
upon exiting the extruder; and extruding the dough
fox an effective time and at an effective temperature,
pressure and shear to partially gelatinize and swell
but not dextrinize the starch of the farinaceous
material.
DETAILED DESCRIPTION OF THE INVENTION
.. . . . _ _ . _
This invention provides a process whereby
farinaceous material with elevated oil content, that
is oil content of 6% and above can be satisfactorily
expanded, using a low temperature, pressure, and
effective shear extruder system. (All %'s herein
are understood to be percen-ts by weight). The
process is designed to obtain a product where the
natural matrix of grain cells is maintained and
where the starch granules partial gelatinization and
swell without rupturing or substantially dextrinizing.
The necessary cooking temperature results from
heating the extruder barrel and by the mechanical
heat which results from torque friction. The cooking
of typical direct steam expanded cereals results
primarily from mechanical energy.
Before proceeding to a more detailed description
of the invention, it is necessary to define some
relevant terms.
z~
- 6 -
By the term "farinaceous material" lS meant
that the formula consists of grain materials such as
oat ~roats, oat, wheat, rice, corn, peanu-t, etc.,
10ur; grits; full fat, partially or wholly defatted
05 germs; bran fractions optionally milled to a certain
particulate size; refined fractions of grain like
gluten, starches or oils; as well as lesser optional
fractions of desirable non-grain materials such as
whole or ground seeds, like sesame seed; beans, like
full fat, partially or wholly defatted soy; seeds
like rape, sunflower, etc; and/or fractions thereof
i.e., protein isolates, oil extracts.
By the term "film forming protein" is meant,
that the protein molecules, like grain gluten,
readily forms films when native and form moisture
barriers when heated.
The term "branll is used in the trade to describe
a mix-ture of several botanical tissues: pericarp
(fruit coat), seed coat (the pericarp and seed coat
are highly adherent at maturity), nucellus, and the
outer portion of the endosperm, the aleurone layer.
By the term 'Ibran fiber'l is meant a polymeric
carbohydrate moiety of the bran which is not digest-
able by humans and which is also known as dietary
fiber, and which generally comprises 20 to 90% o~
commercially available bran meal fraction.
By the term "partial gelatinization" is meant
that most the starch granules have hydrated and
begun to gelatinize and swell, but have not begun to
rupture and dextrinize.
By the term "oat bran" is meant the fiberous
fraction, sifted from oat flour, which could have
various dietary fiber content. However, for conven-
ience in this application the oat bran has a 15%
dietary fiber content.
~2479;~6
The term "oil" in the p.resent invention includes
vegetable oils as well as animal fat. Vegeta~le
oils predominately glycerol fatty acid esters are
extracted from a variety of plant seeds nuts, beans
05 and fruits. Sources of vegetable oil are soybeans,
cottonseed, peanut, corn germ, olives, coconut,
sesame, sunflower seeds, cocoa beans and the like.
Animal fats are generally obtained by processing the
fatty tissues of hogs, cattle or fowls.
The term "hot fluid" according to the present
invention refers to a fluid such as milk having a
temperature ranging from 90F to 180F, preferably
between about 103F and 150F; wherein the product
produced according to the present invention is
contacted with said hot fluid and maintains its most
preferred organoleptic tex-tural integrity for at
least 5 minutes but p.referably up to about 10 minutes,
and its structural integrity in excess of 20 minutes.
By -the term "effective shear conditions" is
meant extrusion conditions whereby the extruder is
operating at a low screw speed; low extrusion
temperature, that is, temperature ranging from 170F
to 240F; and high moisture, that is, moisture
ranging from 24% to 34%. Under these conditions -the
resulting product exhibits low expansion, high
density, low water soluble solid content, and retains
its shape in hot and cold fluid, such as milk.
In contrast, under high shPar conditions the
product exhibit the following characteristics: high
expansion, fluffy light density, high levels of
water soluble solid conten-t, and looses its textural
integrity in hot water. Whereas, under low shear
conditions the results are totally opposite to
extrusion under high shear condition. To enhance
expansion under effective shear conditions, a gas is
~%~z~
incorporated into the formula-tion as it passes
through the extruder.
The first step of the present invention involves
feedin~ farinaceous materials having at least 6% oil
05 and water into an extruder wherein said water is in
effective amounts to prepare a dough. The farinaceous
material can be from a single source, such as 100%
oats, or it can be derived from a variety of sources
as set forth above.
It is desired that the farinaceious material or
materials used in the present invention have an oil
content of at least 6%. Preferably the oil content
ranges from 6 to 16%, however, levels of 7 to 14%
are more preferred. The oil can either be added oil
or oil present in the farinaceous material. Oil,
being hydrophobic in nature has positive attributes
when used in cereal products. The oil contributes
to maintainin~ the structural integrity of the
cereal product when hot fluids such as milk is
added.
In the present invention a formulation containing
6 to 16% oil and having a starch content of about 40%
to 75% and preferably 5~% to 65% can be successfully
ex-truded into direct expanded products.
In a preferred embodiment of the present inven-
tion the farinaceous material is substantially 100%
oat. A 100% oat breakfast cereal is preferred not
only for its high oil and protein content, but also
because of the wholesome and nutritious image asso-
ciated with oat products. This good image is well
justified by the pleasant flavor and the naturally
high level and ~uality protein and fiber. Also, as
a further advantage, the hiyh level of natural
antioxidants present stabilizes the polyunsaturated
fat content of the oat flour.
~47~6
It is also preferred in the present invention
that ~hen bran is employed such as oat bran tha~ it
be micromilled to a desirable particle size. This
can be accomplished by micromi~ling the flour or by
05 separating the bran and recombining with the flour
a~ter micromilling at any proportion desired. In a
situation where whole grain such as oats is micromilled,
the protein associated with the fibrous fraction
becomes exposed. When a whole oat formula is cooked
or extruded in the presence of trisodium phosphate
the flavor is further enhanced.
~ n option for carrying out the present invention
is to incorporate in the farinaceous formula a high
level of a film forming protein and/or increased
level of bran. A suitable level of film forming
protein naturally present or added should range from
about 6.5% to 30%, preferably from about 11% to 23%
and more preferably from about 1~% to about 18%.
In the formulation a suitable level of bran,
expressed as dietary fiber, should range ~rom 1% to
30% and preferably from 5% to 15%.
When the bran is micromilled to a desirable
particle size, the bran micromilling ser~es several
purposes; a less gritty product results with better
eating characteristics; the micromilled fiber par-
ticles diminish the undesirable effects of the high
oil content; micromilled bran impart desirable
textural characteristics to the finish product by
resisting the development of sog~iness whether
consumed with hot or cold fluid such as milk; makes
the product nu-tritionally more desirable; and imparts
more flavor to the product.
Micromilling the bran or whole oats as referred
to in the application shall refer to -the production
of an average particle under 120 micron in size, a
~;~47~:6
-- 10 --
particle size unattainable in most commercially
available mills. An Impact Mill manufactured by
Vortec Products Company, (Long Beach, CA), will
grind material to a selected siæe range. The particle
05 size of -the bran or oats in the present invention
should range from 5 to 120 microns. It is preferred,
however, that the particle size be about 20 to
80 microns and more preferably about 60 microns.
In the present invention the level of moisture
in the formula must be in amounts effective to form
a dough and suitably ranges from 24% to 34%, and
preferably 28% to 32%. The farinaceous material
naturally contains about 8% to 14% moisture.
Accordingly, 10% to 26% moisture should be added,
preferably 18% to 22%. The levels of moisture
typically added by the State of the Art extrusion to
direct expanded cereals is in the 0-12% range. By
increasing the moisture level, comparatively gentle
processing parameters are achieved, such as decreased
temperature, pressure and shear in the extruder.
As some moisture is flashed off upon extrusion
the moisture content of the product exiting the
extruder ranges from about 16% to about 28%, prefer-
ably between about 20% and about 25%.
The farinaceous material, water and other
preferred ingredients are mixed and kneaded to
prepare a homogenous dough. This mixing and kneading
process can be carried out in a first stage or
section of the extruder which has temperatures below
the cooking range of the ingredients, i~e., below
about 130F (55C). Alternately, the mixing can be
carried out in a batch process or continuous mixer
and then fed into the extruder.
79;26
The farinaceous materials with at least 6% oil
and proper amount of water are extruded at low
temperature, pressure and effective shear conditions
in order to achieve the desired product of the
05 present invention. At low temperature, pressure and
shear conditions, sufficient steam is not generated
wi~hin the extruder to expand the product as it
exits the extruder die orifice. Without expansion
the resulting extrudates have a texture similar to
cooked pasta. In order to affect expansion while
extruding at low temperature, pressure and shear
condition, a gas is incorporated. This can be done
either by generating from gas forming materials
which are added to the formula or by injecting gas
directly into the extruder barrel, or by other
suitable techniques. Low temperature and pressure
processing reduces the surging and slippage within
the extruder which is due to the high oil level.
The extrusion conditions (e.g., temperature and
shear etc.) are less severe than those employed in
typical high temperature cereal extrusion processes
where steam puffing provides an aerated product.
Preferred gas forming agents include ammonium
carbonate, solid carbon dioxide and sodium bicarbonate
as well as carbonates of other metals. The metals
carbonates are employed in combination with gas
releasing agents such as acid phosphates. ~nother
source of gas may include internal gas generators,
such as yeast. Another embodiment involves in~ecting
a gas such as carbon dio~ide or nitrogen, into the
dough during the extrusion. These beneIicially
result in an open foamy cell structure which is
similar to steam expanded starch-based cereal products.
926
- 12 -
The dough is subjected to extrusion tempera-
tures effective to partially gelatinize and swell
but not dextrinize the starch, and to denature the
protein. Suitable e~trusion temperatures should
05 range from between about 170F to 240F, preferably
between about 190F and 230F. Thes~ -temperatures
are suitable for achieving the desired product. The
temperature and pressure conditions and the extruder
screw element design are adjusted so that minimal
effective shear conditions are achieved. At this
temperature and gas inclusion conditions, suitable
head pressures within the extruder should be between
about 200 psig to ~00 psig, and preferably between
about 300 psig to 500 psig. Minimal shear condi-
tions within the extruder are also achieved byincreasing the moisture level of the dough. Under
these conditions, the protein hydrates and denatures
into a matri~ while the hydrated, ~elatini7ed and
swollen starch granules remain essentially
~o undextrinized, and the oil is maintained in the
matrix of the dough without significant expression.
The length of time the mixture remains in the
extrudex is dependent upon the temperature, pressure,
shear, etc., but generally will be within the range
of 15 to 45 seconds and preferahly within the range
from 20 to 32 seconds.
The shear conditions are controlled by select-
ing proper extruder parameters i.e., pitch, threat
number and rpm of the screw, feed rate, moisture
level, temperature and pressure conditions.
The work done on the dough is estimated to ~e
within a range of 40 to 120 watt hours per pound in
a single screw extruder and in the case of a twin
screw extruder between 80 and 180 watt hours per
pound. These data are calculated by the amperage and
~4~
- 13 -
voltag~ employed with the dough ~eing run in the
extruders less the amperage and voltage with the
extruders running with water only. A single or twin
screw extruder may be employed, with a single screw
05 ex-truder being preferred as it provides a different
shear profile exerted on the extruded dough.
The extruder according to the present invention
may employ screw pitch, thread design, and depth of
flight which are effective to obtain low shear
conditions. Short, intense compression sections are
applied only to maintain the gas atmosphere.
Upon exiting the extruder the degree of expansion
(puff) will be dependent upon the extruder processing
parameters, amount of gas forming materials pres~nt
and the composition of the formula.
The extrudates exiting the extruder can be cut
into desired shapes, and dried/toasted or first
partically dried, cut into the desired shape then
completely dried/toasted.
The present invention could be applied to
several other product areas, beside the already
mentioned expanded hot or cold breakfast cereals.
Such products could form the solid, particulate base
of a dessert such as Trifle, consumed with a hot or
cold custard. It could also be used for sweet and
savory flavored snacks like meat or cream filled
tubes, "cheese sandwich", sesame stick, potpourri or
other products, shelf stable, refrigerated or frozen.
Since an elevated oil formula with optional
high protein content and added fiber will resist
sogginess when in contack with hot and cold fluids,
-the procedure could also be used to make soup or
salad croutons. Due to the relatively gentl~ heat
process, the extruder feedstocks could be flavored
79;~;
- 14 -
or particulate material could be maintained without
de~radation throughout the extrusion process.
EXAMPLE I
A cereal formula consisting of 100% commercial
05 oat flour with an overall oil content of 7%, was fed
into an extruder. To produce an expanded aerated
product 2% baking powder was also added to the flour
as a gas forming material. The feed rate for the
open-screw feeder was set at 98 lb/hr. (44 kg./hr.).
The wa~er was fed into the extruder at a rate of
18 lbs/hr. (9 kg/hr.).
In order to extrude the dough mixture, a single
screw extruder made by the Wenger Corporation,
Sabetha, Kansas, was employed. The approximate
operating conditions for the Wenger Model X-20
extruder were as follows: screw RPM 250; head
pressure 450 psig (32 kg/cm2); extruder barrel
temperatures were maintaind by heating as follows:
~1 55F (13C), ~2 90F (32C), #3 225F (107C), ~4
20 225F (107C), #5 175F (80C). The configuration of
the screw consisted o conveyance screws for barrels
#1, ~2, #3, and ~4 in that they had a constant depth
oE 0.4 inches (10 mm) and a constant pitch of 1.9
inches (48 mm), with the screw within barrel ~5 at
the die end having a depth of 0.2 inches (5 mm) and
a pitch of 1.9 inches ~48 mm) with the diameter
decreasing from 3.3 to 2.5 inches (84 ~m to 64 mm)
through a length of 4.5 inches ~114 mm). This screw
configura-tion contributes significantly to the
effective shear condition necessary for dough extru-
sion, with the screw section closest to the die (in
barrel #5) being tapered (decreasing in diameter) to
effectively extrude through the die orifice. Steam
locks were placed between screw section 2 and 3, 3
and 4, and ~etween 4 and 5. The die consisted of a
~Z4~7~26
3/4 inch thick die spacer, with 3, each 3/8 inch
circular holes, followed by a backup die 3/4 inch
thick, with 8, each l/8 inch circular holes, followed
by the die plate with a 4 lobe opening and center
05 pin with a total open area of 0.0123 s~uare inch
(0.08 cm ). The work done on the mixture (dough~
was estimated to be about 50 watt-hr/lb and the
total residence time of the dough through zones ~2,
#3, #4, and #~ was 30 seconds.
The extrusion process consisted of placing the
feeder, containing the mixture, over the inlet
opening of the extxuder and adjusting the machine to
the conditions described above. An excellent cereal
type product with a cohesive texture was obtained.
In the cereal product the starch was partially
gelatinized but not dextrinized and the matrix was
substantially undisrupted. The product was sliced
with an Urschel Slicer, air dried and toasted at
375F for 1.5 minutes to obtain the finished cereal.
The dried cereal had a light, crisp airy structure
and good texture retention in hot fluids like milk
or custards. It was also determined that the textural
integrity was maintained beyond 20 minutes standing
in said ho-t fluids, like milk or custard.
EXAMPLE II
A cereal formula consisting of 40% micromilled
oat bran [40 micron siæe] and 60% regular oat flour
was mixed thoroughly and fed into an extruder. The
overall ~ormula had a protein content of 18%, bran
fiber content of 17.5% and an oil content of 6.8%.
To produce an expanded cereal product 1.8% baking
powder, a gas forming material was also added -to the
mixture. The feed rate for the open-screw feeder was
35 set at 100 lb/hr. (45 kg./hr.). The water was
~L2L~79~26
- 16 -
fed into the extruder at a rate of 20 lbs/hr. (9 kg/hr.).
In order to extrude the dough mixture, a single
screw extruder made by the Wenger Corporation,
Sabetha, Kansas, was employed. The approximate
05 operatiny conditions for the Wenger Model X-20
extruder was as follows: screw RPM 275; head
pressure 600 psig (42 kg/cm2); extruder barrel
temperatures were maintained by heating as follows:
#1 50F (10C~, #2 90F (32C), #3 225F (107C), #4
225F (107C), ~5 175F (80C). The configuration o
the screw and the die and their effect was the same
as in Example I. The work done on the dough was
estimated to be about 70 watt-hr/lb and the total
residence time of the mixture (dough) through zones
#2, #3, #4, and ~5 was 28 seconds.
The extrusion process consisted of placing the
feeder, containing the dough mixtures, over the
inlet opening of the extruder and adjusting the
machine to the conditions described above. An
excellent cereal type product with a cohesive
texture was obtained. In the cereal product the
starch was partially gelatinized but not dextrinized
and the matrix was substantially undisrupted. The
product was sliced with an Urschel Slicer, air dried
and toasted at 400F for 1 minute to obtain the
finished cereal product. The puffed cereal had a
fine airy and crunchy texture when consumed dry.
- The product had a cookie-like texture and retained
its shape in hot fluid like hot milk.
EXAMPLE III
A cereal formula consisting of 57% commercial
oat flour, 37% micromilled oat bran [40 micron size]
and 5% commercial barley malt and 0.9% tri-basic
~479;2~
sodium phosphate dodecahydrate with an overall oil
content of 7%, was mixed thoroughly and fed into an
extruder. To produce an expanded cereal product 2
baking powder as a gas forming material was also
05 added to the mixture. The feed rate for -the open-
screw feeder was set at 115 lb~hr. (5~ kg./hr.~.
The water was fed into the extruder at a rate of
27 lbs/hr. (12 kg/hr.).
In order to extrude the dough mixture, a single
screw extruder made by Wenger Corporation, Sabetha,
Kansas, was e~ployed. The approximate operating
conditions for the Wenger Model X-20 extruder was as
follows: screw RPM 275; head pressure 500 psig
(35 kg/cm2); extruder barrel temperatures were
15 maintained by heating as follows: #1 50F (10 C),
#2 150F ~32C), #3 225F (107C3, ~4 225F (107C),
#5 175F (80C). The configuration of the screw and
the die and their effect was the same as in Example I.
The work done on the dough was estimated to be about
100 watt-hr/lb and the total residence time of the
mixture (dough) through zones #2, #3, #4, and #5 was
28 seconds.
The extrusion process consisted of placing the
feeder containing the dough mixtures, over the inlet
opening of the extruder and adjusting the machine to
the conditions described above. An excellent cereal
type product with a cohesive texture was obtained.
In the cereal product the starch was partially
gelatinized but not dextrinized and the matrix was
substantially undisrupted. This product was sliced
with an Urschel Slicer, air dried and -toasted at
375F for 1.5 minutes to obtain the finished cereal
product. The cereal attributes were the same as in
.,
:~ 2L,~79;;~ 6
- 18 -
Example I and II. The product held up equally well
in hot and cold fluids like milk.
EXAMPLE IV
A cereal formula consisting of 35% rice flour,
05 40% micr~milled light wheat bran [40 micron size]
and 25% full fat toasted sesame seed was mixed
thoroughly and fed into an extruder. The overall
formula had a protein content of 12.7%, bran fiber
level of 24% and oil content 13.2%. To produce an
expanded cereal product 2% baking powder as a gas
forming material was also added to the mixture. The
feed rate for the open-screw feeder was set at
75 lb/hr. ~34 kg./hr.). The water was fed into the
extruder at a rate of 21 lbs/hr. (10 kg/hr.).
In order to extrude the dough mixture, a single
screw extruder made by Wenger Corporation, Sabetha,
Kansas, was employed. The approximate operating
conditions for the Wenger Model X-20 extruder was as
follows: screw RPM 225; head pressure 350 psig
(25 kg/cm ); extruder barrel temperatures were
maintained by hea-ting as follows: #1 50~F (10 C)~
#2 75F (24~C), #3 225F (107C), ~4 225F ~107C~,
#5 175F (80C). The configuration of the screw and
the die and their effect was the same as in Example I.
The work done on the dough was estimated to be about
115 watt-hr/lb and the total residence time of the
mixture (dough) through zones #2, #3, #4, and #5 was
32 seconds.
The extrusion process consisted of placing the
feeder con-taining the mixtures, over the inlet
opening of the extruder and adjusting the machine to
~he conditions described above. An excellent cereal
type product with a cohesive texture was obtained.
The cereal product the starch was partially gelatin-
7~2~;
-- 19 --
ized but not dextrinized and the ma-trix wa~ substan-
tially undisrupted. The product was sliced with an
Urschel Slicer, air dried and toasted at 375F for
1.5 minutes to obtain the finished cereal product.
05 The puffed cereal had a desirable texture, with
unique properties, such as holding up equally well
in hot and cold fluids like milk. The product also
had an excellent toasted sesame flavor and taste.
E~AMPLE V
A cereal formula consisting of 35% rice flour,
25% micromilled corn bran [~0 micron size] and 40%
full fat toasted corn germ was mixed thoroughly and
fed into an extruder. The overall formula had a
15 protein content of 11.3%, bran fiber 27% and an oil
content of 12.4%. To produce an expanded cereal
product 1.5% baking powder as a gas forming material
was also added to the mixture. The feed rate for
; the open-screw feeder was set at llO lb/hr. (50 kg.
hr-)- The water was fed into the extruder at a rate
of 24 lbs/hr. (ll kg/hr.).
In order to extrude the dough mixture, a single
screw extruder made by ~enger Corporation, Sabetha,
Kansas, was employed. The approximate operating
conditions for the Wenger Model X-20 extruder were
as follows: screw RPM 250; head pressure 500 psig
(35 kg/cm2); extruder barrel temperatures were
maintained by heating as follows: #1 50F (10C), #2
150F (66C), #3 230F (110C), #4 230F (110C), #5
30 200F (93C). The configuration of the screw and the
die and their effect was the same as in ~xample I.
The work done on the dough was estimated to be about
100 watt-hr/lb and the total residence time of the
mixture (dough) through zones ~2, #3, #4, and #5 was
30 seconds.
124~7~2~
- 20 -
The extrusion process consisted of placing the
feeder, containing the mixtures, over the inlet
opening of the extruder and adjusting the machine to
the conditions described above. An excellent cereal
05 type product with a cohesive texture was obtained.
Within the cereal product the starch was partially
gelatinized but not dextrinized and the matrix was
substantially undisrupted. The product was sliced
with an Urschel Slicer, air dried and toasted at
375F for 1.5 minutes to obtain the finished cereal
product. The puffed cereal had a desirable texture,
with unique properties similar to those in the
previous examples.
EXAMPLE VI
A cereal formula as in Example III having an
overall oil content o 7%, was mixed thoroughly and
fed into the extruder. To produce an expanded
cereal product 2% baking powder as a gas forming
material was also added to the mix-ture. The feed
rate for the open-screw feeder was set at 75 lb/hr.
(34 kg./ hr.). The water was fed into the extruder
at a rate of 21 lbs/hr. (10 kg/hr.).
In order to extrude the dough mixture, a single
screw extruder made by Wenger Corporation, Sabetha,
Kansas, was employed. The approximate operating
conditions for the Wenger Model X-20 extruder was as
follows: screw RPM 265; head pressure 300 psig
(21 kg/cm ); extruder barrel temperatures were
maintained by hearing as follows: #1 50F (10C), #2
80F (27C), #3 200F (98C), #4 200F (98C), #5
225F (107C). The configuration of the screw and
its effects were the same as in Example I. The die
consisted of a 3/4 inch thick die spacer with 3,
each 3/8 inch circular holes, followed by a backup
~4~9%6
die 3/4 inch thick, with 8, each 1/8 inch circular
holes, followed by the die plate having a ring shape
with a total opening area of 0.0123 s~uare inches
(0.08 cm ). The work done on the dough was
05 estimated to be about ~0 watt-hr/lb and the total
residence time of the mixture (dough) through zones
#2, #3, #4, and $~5 was 29 seconds.
The extrusion process consisted of placing the
feeder, containing the mixtures, over the inlet
opening of the extruder and adjusting the machine to
the conditions described above. An excellent cereal
type product with a cohesive texture was obtained.
In the cereal product the starch was partially
gelatinized but not dextrinized and the matrix was
substantially undisrupted. The product was air
dried and toasted a-t 375F for 1.5 minutes to obtain
the desired cereal product. The puffed farinaceous
product had a desirable texture with a tube shape
and a hollow center. The hollow center was suitable
-20 for filling soft creamy materials e.g., cre~n butter,
peanut butter, etc. A bi-textured farinaceous
product was obtaine*.
EXAMPLE VII
A fomula as in Example III with an overall oil
content of 7% was mixed throughly and fed into an
extruder. To produce an expanded aera-ted product 2%
of baking powder, as a gas forming material was also
added to the above mixture. The feed rate for the
30 open-screw ~eeder was set as 250 lbs/hr (114 kg/hr).
The water was fed into the extruder at a rate of
63 lbs/hr ~28 kg/hr).
In order to extrude the dough mixture, a co-rotat-
ing twin screw extruder made by Werner & Pfleiderer
- 22 -
(W/P) Corporation, Ramsey, New Jersey was employed.
The approximate operating conditions for the W/P
Model ZSK-57 were as follows: screw RPM 300; head
pressure 500 psig (35 kg/cm2); extruder barrel
05 temperatures were controlled by heating as follows:
~1 150F (66 C), #2 150F ~66C), #3 200F (93C),
#4 220F (104C), #5 ~30F (110C). The configuration
of the screw consisted of five barrel zones; #l zone
had a special deep flight feeding screws; #2 zone
had a conveyance screws; ~3 zone had right handed
30 staggered kneading elements; #4 zone had a
combination of conveyances and left handed 30
staggered kneading elements; #5 zone had neutral
screws that created more even flow and pressure.
The die consisted of one 1 1/2 inch thick spacer,
one 1 1/4 inch thick die hole and two star shape
dies with total area of 0.0246 s~uare inch (0.16 cm2)
opening. The work done on the dough was estimated
-to be about 1~0 watt-hr/lb and the total residence
time of the mixture (dough) through zones ~2, #3,
~4, and ~5 was 30 seconds.
The extrusion process consisted o~ placing the
feeder, containing the mixtures, over the inlet
opening of the extruder and adjusting the machine to
~5 the conditions descri~ed above. An excellent cereal
-type product with a cohesive texture was obtained.
This product was sliced with Urschel Slicer and was
air dried and toasted at 375F for 1.5 minutes to
obtain the finished product. The product had similar
characteristics to the Example III.
