Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION
CORN SPIRALS AND METHOD OF MANUFACTllPiE
BACKGROllND OF THE IMVENTION
Small snack food products have been manufactured in a wide
variety of shapes and sizes, inc]uding scoops, cups, containers,
cones, triang]e3, roll, squares and curls. Corn chips and potato
chips are generally planar, concave or ridged. Pretzels are long,
fihort, thick or thin, and twisted into a variety of shapes.
Snack food products have been made from masa in the past,
but the masa has been made in a conventional manner by ~rinding.
Grinding is traditional, but produces masa havin~ coarse particle
sizes because all attempts to produce verv fine particle sizes by
grinding generate enough frictional heat so that the masa will
become overly cooked. This has led the public to expect certain
mouth-feel and texture characteristics in snack products produced
from masa.
Corn has also been processed for use in making snacks on
comminution devices, such as~ Fitz mills or hammermills, with a
cutting action that reduce particle size by ~ cutting action rather
than by a grinding action. Generally, the product of such a
process is a masa of reduced cohesion between its particles that
resu]ts in u characteristic mouth-feel and texture in products made
from this kind of material.
Prior art processes for manufacturing corn flour or corn chip
snack products are also varied. These processes all have at least
one grinding 6tep.
Often the manufacturer of n snack food product will begin the
manufacturing process with a prepared flour or meal, which is
used to form a dough, masa, or the like. In this case, the
manufacturer has no concern, generally, with the initial material,
but contributes to the product just the formulation and
manufacturing steps that utilize the flour or meal as a raw
material. Where the manufacturer does produce the flour or meal,
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it i6 genernlly produced by a grinding, cuttLng, or attrition step.
Since each of these processes requires a different piece of
equipment, generally only one type of operation is performed.
SUMMARY OF THE INVENTION
In its broad aspects, the invention in one embodiment is a
cooked snack food product comprising a ribbon-like piece of fried
dough made from a masa that has been ground and then further
processed to reduce particle size by comminution involving a
simultaneous gratinK and cutting action.
According to a preferred embodiment of the invention, this
ground, grated and cut masa is extruded through dies that form a
ribbon-like sheet. In a preferred embodiment, this sheet is
extruded through dies that also twist it to have a spiral shape.
The extruded spiral material is cut into suitable lengths, which are
then fried in hot oil to a ffnal moisture content in the range 0 . 5~6
to 1. 5% by weight. The spiral shaped product is marketable and
appealing to consumers because of the thinness of the masa ribbon
from which it is manufactured. The thinness of the ribbon is
dependent upon the reduction of the number of large particles in
the masa. A fine masa provides a more desirable texture in the
helical shaped product due to the second milling step of the
process. The 6econd milling step is a comminution of the masa
particles by sirnultaneous grating and cutting actions. Although
the masa produced by this process may be used to produce a
snack food product of any shape, the spiral shape emphasizes the
desirable texture for the consumer.
A maximum particle size of 0 . 06 inch is insured by forcing
the masa through a plate having perforations of the desired
maximum size, prior to extruding it.
The preferred snack food structure is a spiral having an
axial length of about 2-1/4 inches. The spiral shape gives the
product a unique and pleasant mouth-fee] in addition to making the
spirals particularly adaptable for use with dips. The gaps
between ~lights trap and hold more dip than a comparably-sized
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~lat ribbon chip, and the twisting of the ribbon into spiral form
imparts mechRnical strength against brenking when the ~piral
passes through dip. The texture of the corn spiral is softer and
more delic~te than standard corn chips, due primarily to its
process of manufacture.
The process of the invention involves subjecting a ground
masa to comminution by simultaneous grating and cutting that
reduces the size of the particles in the masa. The comminuted
masa is then screened to insure that the maximum particle size
cannot exceed O . 06 inch . The screened masa is then extruded
through a die to a ribbon-like form. The ribbon-like extrudate is
then cut to snack-sized pieces of the desired length, which in
turn are cooked in hot oil to achieve a final product moisture
content in the range 0.5% to 1.59~ by weight.
When beginning the process with whole corn kernels, the
process of manufacturing involves adding water and lime to whole
}cernels of corn and cooking the mixture at the boiling point. Cold
water i8 added to the mixture and the mixture is allowed to stand
for approximately eight hours. The kernels ~re then washed with
additional water to remove the hulls, after which the kernels are
ground between rotating surfaces to form masa.
Masa is a sticky, pliable paste that consists of an
agglomeration of moist, soft particles of different sizes. The masa
is then comminuted in an Urschel Comitrol mill or like device that
has a simultaneous grating and cutting action. This creates a
very fine masa with particles which will not block the narrow
openings of the extruder dies necessary to produce the helical
shape. The finely ground masa is then passed through extruder
and helix-foIming dies. The resulting corn spirals are extruded
downward into a continuous fryer. After frying, the corn spirals
may be seasoned or flavored, then cooled and packaged.
DETAILED DESCRIPTION OF THE INVENTION
In one preferred embodiment, the snack food product of the
invention is a fried and seasoned corn dough product formed in a
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spiral shape. The color of the product is a golden yellow, and
the flavor of the salted product is that of toasted corn. Other
seasonings or flavors that may be applied to the corn spiral to
give it more distinctive tastes are nacho flavoring, barbeque
flavoring, or butter tla~oring.
The soft and delicate texture of these corn 6pirals, as well as
their crunch, is primarily due to the process of manufacture, ~nd
also to the oil and moisture content of the product. The oil
content of these corn spirals is within the range of 28 . 0~ to 36 . 0%,
with an optimum percentage of 34 . 0~, while the residual moisture
content is within the range of 0.5% to 1.5%, with an optimum value
of 1.0~.
The process of manufacturing a preferred snack food product
with these characteristics begins by delivering whole-kernel corn
from its storage silo to a steam-jacketed cooking kettle by means of
a screw conveyor. Approximately 450 pounds of corn form a batch
of convenient size. The preferred type of corn is a pale yellow
Hybrid Variety or a 1:1 blend of white and yellow varieties.
After the corn has been delivered to the kettle, 80 gallons of
water are metered into the kettle and the temperature of the corn
and water mixture is brought to about 150F. At this point, 3
pounds, 11 ounces of lime (calcium hydroxide USP or its
equivalent) are added to the corn and water mixture, and the
entire mixture is cooked for 15~35 minutes after reaching the
boiling point at atmospheric pressure. The steam pressure applied
to the kettle jacket during the cooking stage is about 60 psig.
The cooking time may be varied within the limits given, as
required, in order to obtain the desired oil absorption in the
finished product.
When the cooking stage is completed, the cooked corn is
discharged into a transfer tank. An additional 70 gallons of cold
water are added to the mixture by rinsing the cooking kettle into
the transfer tank. Then the entire corn/water mixture is pumped
into rectangular, stainless steel, open-top soaking tanks of
approximately 240 gallons capacity. The corn is levelled in the
soaking tanks so as to be completely covered with water, and then
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allowed to soak quiescently or preferably 8 hours ~nd 15 minutes
(although the corn may &oak longer, for a maximum time of 12
hours and 15 minutes).
When the soaking is completed, each batch is pumped into a
rotary washer where the corn is washed by spraying with fresh
water. The washing removes corn hulls and other debris, as well
as any residual lime. The hulls are considerably softened from the
previous heat and lime treatment stuge. The washings are
discarded to waste or are taken for by-product recovery.
The washed and drained dehulled corn is then transferred to
rnechanical grinders, where it is ground into masa. The
mechanical grinders operate to grind the corn between rotating
grinding surfaces. The coarseness of the ground masa is
controlled by visual examination, and by adjustment of the
grinding surfaces. A conveyor belt transports the ground masa to
an Urshel Comitrol mill fitted with a ~t30 grinding head. A
A Teflon~lined funnel is located on the top of the Comitrol mill, the
point at which the masa enters. The Teflon surface of the funnel
keeps the masa from sticking to the inside surface of the funnel.
In addition, the entire inside surface of the Comitro] mill, except
for the lid, the impeller, and the grinding head, is also lined with
Teflon .
An oil spray system is mounted above the entrance funnel and
sprays cottonseed oil onto the masa as it enters the Comitrol mill
to be comminuted. The spray rate is about one gflllon of oil per
hour of grinding time. The oil acts as a lubricant to keep the
masa from sticking to the inside of the mill, and also contributes
to the texture characteristics of the finished product.
Also necessary tc insure the delicate texture characteristics
of the corn spirals product is the comminuting step performed by
the Comitrol mill. The mill reduces the size of pnrticles by
simultaneous grating and cutting, rather than grinding. A
mechanical grinder alone could not grind particles as fine as those
comminuted by the Comitrol mill without creating much frictional
heat and consequently turning out an extremely overcooked masa.
Comminution through the Comitrol mill only, without pregrinding,
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produces a masa of reduced cohesion between its particles, which
gives a very different and less desirable texture to the final fried
product .
The Comitrol mill has a rotary impeller that is disposed within
a perforated cylindrical "cutting head". Material that is fed into
the bore of the cutting head is forced by the impeller against the
inner surface of the cutting head and the material is forced by the
impeller through the rectangular perforations in the cutting head.
The portions of the cutting head about the perforations are
sharpened, so that a grating, as well as a cutting action, is
applied to masa that is forced through the perforations by the
impeller. Perforation sizes are generally uniform in a given
cutting head, but different cutting heads have perforations of
different dimensions. The dimensions of the rectangular
perforations in the preferred #30 cutting head are 0.030 inch by
0 160 inch.
In addition to enhancing the texture of corn spirals, the
comminuting step further reduces the size of particles in the masa
which otherwise would have been too large to pass through the
openings of the extruder dies after only the one grinding step.
After having its particle size reduced by the simultaneous grating
and cutting action of the Comitrol mill, the masa is discharged
from the bottom of the Comitrol mill onto a conveyor belt that
transfers the masa to another conveyor belt, which delivers the
masa to a supply hopper located on top of a ~arlin continuous-type
extruder or the equivalent. The moisture content of the masa at
this point i8 about 95% to 54%.
The lYlarlin extruder is a piston-type extruder that is fitted
with a special flared barrel or "bell". The flared barrel is
modified to contain a changeable screen which prevents any large
particles from getting into the dies and blocking them. The
preferred screen is made of 22-gauge stainless steel, and is
perforated with holes that are 3/64ths inch (about 0.05 inch) in
diameter. The holes are staggered, and there are about 131 holes
per square inch. Screens with holes of different sizes may be
used. Generally, the size of the holes of the screen is the same
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as the size of the opening of the die being used, so as to prevent
particles that are too large to pass through the die opening from
reaching said opening. If the screen becomes blocked, it should
be removed and replaced with another screen by means of a
fast-acting screen-changing mechanism. The screen acts as a
"fail-safe" to remove any remaining large particles of masa which
might otherwise have survived the Comitrol mill treatment and
which would severe]y block the extruder dies. Even a slight or
partial blockage of a die would create severe shape distortion of
the resulting corn spiral, resulting in a less desirable product for
the consumer. The comminuting step produces masa with particles
which will not cause rapid blockage of the screen or the extruder
dies. Masa subjected to only the grinding step completely blocks
the screen in a short time and thereby blocks flow of the masa to
the extruder dies. A masa that is the product of a single
grinding step leaves 0.2134%, on a dry weight basis, on the
preferred screen of the inventive process, in contrast to 0.012796,
on a dry weight basis, that remains on the screen ~fter a masa
that has been both ground and comminuted by a Comitrol mill is
passed through the screen. The difference in the amount of masa
left on the screen accounts for the rapid blockage of the screen
that occurs with a ground masa, and the reduced blockage that
occurs with a masa that has been both ground and comminuted by
a Comitrol mill.
The masa is forced by pressure through an elbow-shaped
extruder head, and thence through a spiral-forming die into 26
discrete, twisted ribbons which form spirals that are between 0 . 20
inch and 1. 0 inch, and preferably 0 . 515 inch, in diameter . The
thickness of the ribbon is preferably in the range of about 0 . 055
inch to 0 . 065 inch . Thicknes5es as great as about 0 .100 inch can
be useful, but thinner products are preferred. Spiral shaped
products have greater resistance to breaknge. Each of the spirals
preferably has two flights in 2~" of length. However, the gap
between flights can range from 0 .10 inch to 2 . 0 inches . The
spirals are automatically cut into lengths of about two inches or
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2-1/4 inches by a cutting wire flS they emerge from the extruder
head .
Each spiral as extruded resembles a spiral chute except that
the spiral is not v,1ound on a cylinder but rather is just lwisted on
itself about an axis. The outer edge of each spiral, if extruded
in a perfectly spiral fihape, would define a helix.
The cut masa spirals fall directly into a fryer containing
vegetable cooking oil maintained at a temperature of 400-405F
(204-207C). Mechanical action of the fryer moves the spirals
through the fryer for an average residence time of about one
minute, ~5 seconds. The length of time is adjustable, however, to
correspond with the completion of the frying of the spirals.
Compietion of frying corresponds with cessation of bubbling and a
residual moisture content in the spirals of 1. 5~ or less ~ The free
fatty acid level of the oil in the fryer (a measure of breakdown of
the oil) is maintained at a maximum of 0.40g6.
~ 'hen the corn spirals exit the fryer, they pass through a
tumbler where Ealt is applied at a level equivalent to 1. 3096 of the
finished product. At this point, seasonings or flavorings such as
nacho-cheese, barbeque or butter flavorings may also be applied to
the corn spirals.
The seasoned produc$ is then transported to the packaging
area on conveyors. Cooling of the product occurs during this
period. The product is finally packaged by automatic packaging
machinery, and cartoned.
The foregoing process description is concerned with the
production of a corn-based snack food product in spiral form.
This represents a preferred embodiment of the invention. While
one might expect the fried corn spirals snack food product to be
essentially uniform in size and shape, in fact the extrusion process
is not perfect, and the drop Or the uncooked spirals from the
outlet of the extrusion die to the surface of the hot cooking oil
results in ~n impnct. This impact may cause shape distortions of
various kinds, so that the spirals are not uniform. Similarly,
durin~ transport through the coo~sing oil, the application of heat
often causes some distortion, and jostling with other spirals in the
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fryer may also cause changes in shape. Accordingly, the
packaged spiral products may not be perfect helices. I~ood spirals
are considered to be generally straight, and anything up to a 45
deviation from axial is considered essentially straight. Ilsually
about 50% maximum of the spirals are straight as so defined. When
the bend is more than ~5 from axial, the spirals may be good
products in shape. Generally not more than 20% of the spirals
snack food product are bent more than g5 from axial. The
remaining products will have other degrees of distortion, and
generally up to about 10% of the spiral product will be shorter
than one inch, despite the fact that the production process sought
to produce spiral products of about two inches in len~th.
To make a nacho cheese-flavored corn spiral product, a nacho
cheese seasoning is dusted onto the surface of the fried product in
an amount of about 7% bv weight of the finished fried product,
while still hot from the fryer. Products having other ~lavors may
be produced in similar fashion.
While the preferred snack food product is a corn spiral fried
product produced by the process described in detail above, other
snack food products may be produced that have similar taste,
mouth-feel and texture, but not necessarily the spiral shape.
Thus, the dies may be selected to produce an essentially straight
ribbon that is cut into the desired lengths. Such straight
ribbon-like products come out of the frying operation having ]ess
than straight shapes, of course, because of the happenings
described with respect to the corn spirals that distort them.
Similarly, other dies can be used to produce straight ribbon-like
products with a slight twist. Also, by using suitable manufacturing
techniques, snack food products shaped like cups, scoops, cones,
rolls, and curls, for example, can be produced. In addition,
other cooking techniques such as baking may be used instead of
frying .
The helix-forming dies that are used in the production of the
preferred spiral snack food embodiment of the invention are simply
those helix-forming dies that have traditionally been used by the
pasta industry to make a spiral pasts product called either "rotini"
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or ~Ispiralli~. Other dies are readily available to make
ribbon-shaped products of different shapes, or to form extruded
straight ribbons into other shapes.
In addition to ribbon forms, the masa of the invention is
generally useful in producing cooked snack products in a variety
of shaped forms. Thickness is a problem as to obtaining uniform
cooking, but this can be handled in a variety of ways, as by
microwave cooking, or by a combination of frying with microwave
cooking, or by using hollow shapes.
While the invention has been disclosed in this patent
application by reference to the details of preferred embodiments,
this disclosure is intended in an illustrative rather than in a
limiting sense, as it is contemplated that modifications will readily
occur to those skilled in the art, within the spirit of the invention
and the scope of the appended claims.
