Note: Descriptions are shown in the official language in which they were submitted.
POTATO CHIP
BACKGROUND OF THE INVENTION
[0001]
Technical Field
[0002] The present invention relates to an improved method and system for the
production of a fried potato chip.
Description of Related Art
[0003] Conventional potato chip products are prepared by the basic steps of
slicing
peeled, raw potatoes, water washing the slices to remove surface starch and
frying the potato
slices in hot oil until a moisture content of about 1% to 2% by weight is
achieved. The fried
slices are then salted or seasoned and packaged.
[0004] Raw potato slices normally have moisture contents from 75% to 85% by
weight depending on the type of potato and the environmental growing
conditions. When
potato slices are fried in hot oil, the moisture present boils. This results
in burst cell walls
and the formation of holes and voids which allow for oil absorption into the
potato slices
yielding significant oil contents.
[0005] The oil content of potato chips is important for many reasons. Most
important is its contribution to the overall organoleptic desirability of
potato chips. Too high
an oil content may render the chips greasy or oily and hence less desirable to
consumers. On
the other hand, it is possible to make chips so low in oil that they lack
flavor and seem harsh
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in texture. Some nutritional guidelines also indicate it is desirable to
maintain a diet low in
oil or fat.
[0006] Numerous attempts have been made in the prior art to control the oil
content
in potato chips. However, past attempts are either expensive, use technology
that requires
longer than desirable deoiling dwell time, or have failed to maintain the
desired
organoleptical properties such as taste and texture that have become familiar
to consumers of
traditional potato chips.
[0007] Consequently, a need exists for a process that allows a practitioner to
control
the oil content of a fried potato chip and produce a novel final product that
retains desirable
organoleptical properties similar to traditional potato chips.
2
SUMMARY OF THE INVENTION
[0008] The proposed invention provides a method and system for producing fried
potato chips. In one embodiment, washed potato slices are par-fried by
immersion in hot oil
at a first temperature, and then finish fried by contact with hot oil at a
higher second
temperature. In a preferred embodiment, the finish frying step is accomplished
by a second
immersion frying step.
[0009] The fried potato chips produced according to the present invention can
contain less oil than conventionally fried potato chips, yet retain the
desirable visual, taste,
and textural qualities of the traditionally fried potato chips.
[0010] Other aspects, embodiments and features of the invention will become
apparent from the following detailed description of the invention when
considered in
conjunction with the accompanying drawings. The accompanying figures are
schematic and
are not intended to be drawn to scale. In the figures, each identical, or
substantially similar
component that is illustrated in various figures is represented by a single
numeral or notation.
For purposes of clarity, not every component is labeled in every figure. Nor
is every
component of each embodiment of the invention shown where illustration is not
necessary to
allow those of ordinary skill in the art to understand the invention. In case
of conflict, the
present specification, including definitions, will control.
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BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The novel features believed characteristic of the invention are set
forth in the
appended claims. The invention itself, however, as well as a preferred mode of
use, further
objectives and advantages thereof, will be best understood by reference to the
following
detailed description of illustrative embodiments when read in conjunction with
the
accompanying drawings, wherein:
[0012] Figure 1 is a schematic representation of one embodiment of the method
and system used to produce the potato chip of the present invention.
[0013] Figure 2 is a schematic representation of another embodiment of the
method
and system used to produce the potato chip of the present invention.
[0014] Figure 3 is a schematic representation of another embodiment of the
method
and system used to produce the potato chip of the present invention.
[0015] Figure 4 is a graph showing the RVA profiles for various potato chip
samples.
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DETAILED DESCRIPTION
[0016] The present invention is directed to a method and system for producing
fried
potato chips. The inventive potato chips may, in one embodiment, comprise an
oil content
that is lower than known and commercially available potato chips. In general,
when potato
slices are fried in hot oil, moisture leaves the food product as steam, and
the slices absorb
some of the oil they are fried in. The embodiments described below are
directed towards
fried potato slices that comprise a specific range of thicknesses, and that
have been washed
prior to frying. Such fried potato slices are referred to in the art as
"potato chips" and can be
differentiated from thicker, unwashed potato slices that have been fried,
which are referred to
in the art as "kettle chips" or kettle-fried chips. The invention is designed
in one embodiment
to reduce, but not eliminate, the overall oil content of the finished potato
slice.
[0017] Figure 1 depicts a preferred system that can be used to produce the
potato
chips of the present invention. Whole potatoes stored in hopper 2 are
dispensed into a slicing
apparatus 4 which drops potato slices into a water wash 6. In order to produce
potato chips,
the potatoes are sliced to produce potato slices that comprise a thickness
between 0.040
inches and 0.080 inches, with a target of 0.053 inches. In a preferred
embodiment, the range
of slice thicknesses for potato chips is from 0.040 inches to 0.063 inches.
Potato slices with
thicknesses that fall above this range are used in the art to produce "kettle
chips" and other
thicker potato products, which are not called "potato chips" by a skilled
artisan.
[0018] In a preferred embodiment, the frying oil entering the fryer is
maintained at
an initial temperature between about 320 F to about 380 F more preferably
between about
335 F and about 370 F. Any conventional frying medium can be used in
accordance with
various embodiments of the present invention, including frying mediums with
digestible
and/or non-digestible oils. In one embodiment, the fryer is a continuous
single flow or
multizone fryer which utilizes devices such as paddle wheels, 14A and 14B, and
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submergible conveyor belt 16 to control the flow of potato slices (not shown)
through the
fryer 10.
[0019] In one embodiment of the present invention, the potato slices are par-
fried to
an intermediate moisture content and then removed from the fryer, preferably
by a perforated
endless belt conveyor 18 (sometimes referred to as a takeout conveyor). If no
hot oil is added
to the frying oil or if the oil is not otherwise heated during frying, at the
location the
perforated endless belt conveyor 18 contacts the frying oil, the frying oil
comprises a final
par-fry temperature of between about 290 F to about 330 F and more preferably
between
about 300 F to about 320 F. The final par-fry oil temperature, as that term is
used herein, of
the first immersion frying step is the oil temperature at the location of the
takeout means. For
a continuous frying process, the takeout means will typically comprise a
takeout conveyor 18,
as depicted in Figure 1, and for a batch process the takeout means will
typically be a
perforated basket or takeout conveyor. In either case, the final par-fry oil
temperature is the
temperature of the oil at the location of the potato slices as they are being
removed from the
oil by the takeout means.
[0020] In one embodiment, the potato slices exit the fryer comprising an oil
content
of between about 30% and about 45% by weight, and an intermediate moisture
content above
2% by weight, or in another embodiment above 3% by weight. In one embodiment,
the
intermediate moisture content is between about 1.5% and about 15% by weight,
or in another
embodiment, between about 3% and about 10% by weight, or combinations of the
foregoing
ranges. In a preferred embodiment, the par-fried potato slices comprise an
intermediate
moisture content between about 2% and 10% by weight, and most preferably
between about
3% and 6% by weight. Preferably, the final moisture content of the potato
slices is less than
about 10%. and more preferably less than about 5%, by weight of the potato
slices below the
intermediate moisture content of the potato slices.
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[0021] As shown in Figure 1, the par-fried slices are then subjected to a hot
oil
finish frying step, which in a preferred embodiment, is accomplished by
transferring them to
a second immersion frying tank 22. The transfer between the first immersion
frying step and
second immersion frying step can occur by use of takeout conveyor 18 and,
optionally,
transfer conveyor 20. In a most preferred embodiment, transfer conveyor 20
runs at a higher
speed than takeout conveyor 18, thereby reducing the thickness of the potato
chip bed, or
substantially monolayering the potato chips on the transfer conveyor. Second
immersion
tank 22 may comprise a submerger belt 24, and the finished potato chips can
flow over front
lip 30, or be removed by another takeout conveyor (not shown).
[0022] Figure 2 depicts another embodiment of a hot oil finish frying method
and
system comprising at least one hot oil curtain disposed above the takeout
conveyor. A hot oil
curtain 46 is a volume of oil flowing from an oil dispenser 44 above the
takeout conveyor 18,
through the potato slices on the takeout conveyor and the takeout conveyor.
Preferably, the
hot oil curtain 46 spans substantially the entire width of the takeout
conveyor. Oil from the
hot oil curtain 46 can be collected underneath the takeout conveyor in its own
receptacle
separate from the hot oil used for immersion frying, or can drain into the hot
oil used for
immersion frying. The oil used for the hot oil curtain is fed from an oil
source 40, optionally
through a heat exchanger 42, and into the oil dispensers 44 above the takeout
conveyor 18.
In one embodiment, the oil source 40 is a source of fresh or reconditioned
oil, and in another
embodiment, the oil source 40 is the same oil used in the immersion fryer 10.
In one
embodiment, the temperature of the hot oil curtain is greater than the final
par-fry oil
temperature of the first immersion frying step.
[0023] In still another embodiment, depicted in Figure 3, the products being
fried
by immersion in hot oil can be subjected to a hot oil finish frying step by
providing a
submerged hot oil curtain inside the frying oil 10. One example of a submerged
hot oil
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curtain is depicted by the shaded region 56 of Figure 3. In the embodiment
depicted in
Figure 3, the submerged hot oil curtain 56 is provided by at least one hot oil
dispenser 54
located above the product bed 50 as it passes under the submerger 16. In a
preferred
embodiment, the submerged hot oil curtain 56 is supplemented by at least one
oil dispenser
54 located below the product bed 50 as it moves from the submerger 16 to the
takeout
conveyor 18. The oil dispensers 54 can be fed by a fresh oil source 40 which
is heated by a
heat exchanger 42, but may also be fed, in whole or in part, by oil recycled
from the fryer.
[0024] Because only a short hot oil finish fry time is required to realize the
advantages of the present invention, the submerged hot oil curtain can
represent a narrow
band or region of oil between the submerger 16 and takeout conveyor 18. The
hot oil is
restricted to the regions inside the fryer near the oil dispensers 54 because
the recirculation
system drain 62 is located near the product exit end of the fryer. The
recirculation system
uses at least one pump 58 and heat exchanger 60 to recycle the oil to the
product entrance end
of the fryer. This maintains a well-defined region of hot oil in close
proximity to the
submerger 16 and takeout conveyor 18 that constitutes the submerged hot oil
curtain 56.
[0025] Applicants have determined that the vapor pressure of water inside a
potato
slice varies at different product temperatures and moisture contents. It was
found that in
order to maintain the vapor pressure inside the potato chip above 14.7 psia
(or approximately
atmospheric pressure), the product temperature must be above about 270 F to
310 F at
moisture contents ranging from 1% to 2% moisture content. Therefore,
Applicants theorize
that the product temperature must be at least this high in order for water
vapor inside the
potato chip to resist the absorption of oil via capillary action. In fact, the
product temperature
must likely be even higher than these temperatures to overcome gravitational
and capillary
forces that may also favor absorption of oil, and will certainly need to be
higher if water
vapor is used to expel oil from the void spaces within the potato chip.
Moreover, the oil
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temperature must be higher than the desired product temperature to account for
the
commercially needed high rates of heat transfer between the oil and the
product. In fact,
Applicants have discovered that when an oil temperature of 340 F is used in
the finish frying
step, no oil is removed or absorbed in the final product as compared to
products that are fried
to their final moisture content in one frying step. By contrast, a finish
frying oil temperature
of 290 F causes more oil to be absorbed by the final product, and a finish
frying oil
temperature of 390 F causes less oil to be absorbed in the final product.
[0026] In one embodiment, the temperature of the oil in the second immersion
frying step is at least about 350 F, and in a preferred embodiment at least
about 385 F. In a
preferred embodiment, the temperature of the oil in the second immersion
frying step is
greater than 340 F and less than 415 F. In another embodiment, the difference
between the
final par-fry oil temperature in the first frying step and the initial finish-
fry oil temperature in
the finish frying step is at least 30 F. In a preferred embodiment, the
difference is at least
50 F.
[0027] In one embodiment, the potato slices are subjected to a first frying
step by
immersion in oil at a first temperature, followed by a second frying step by
immersion frying
in hot oil at a second temperature, which is greater than the first
temperature. A known
process for continuous immersion frying of potato slices uses an initial oil
temperature of
350 F to 360 F, a final oil temperature of about 250 F to 320 F, and a
residence time of
about 190 seconds. If hot oil is not added to the system, the oil cools as the
food pieces are
fried. The potato slices exit this frying process at a moisture content of
about 1.4% by
weight. In one embodiment of the inventive process described herein, potato
slices are
immersion fried at about the same initial oil temperature and on the same
continuous frying
equipment, but the residence time is reduced to about 80 seconds to 180
seconds, or in a
preferred embodiment the residence time is reduced to about 80 seconds to 130
seconds.
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Then, as described above, the slices are removed from the hot oil, preferably
as a product bed
on a takeout conveyor, and subjected to finish frying by transferring the
slices to a second
immersion frying step.
[0028] In a preferred embodiment, the second immersion frying step is a short
time,
high temperature immersion frying step. In this embodiment, the takeout
conveyor from the
first step can feed the par-fried potato slices into a second volume of oil
maintained at a
higher temperature than the oil temperature used for the first immersion
frying step. More
than one conveyor, or a different transfer means, may be used between the
frying steps. For
par-fried potato slices, preferably the residence time in the second immersion
fryer is less
than about 10 seconds, and more preferably less than about 5 seconds, to bring
the moisture
content of the potato slices to a final moisture content of less than 2% by
weight. The finish
fried potato slices can be removed from the second volume of oil by any
convenient means,
such as a second takeout conveyor, a perforated basket, or flowing over a weir
at the end of
the fryer.
[0029] Applicants have discovered that the inventive process has several
surprising
advantages over known frying methods.
[0030] First, the fried food products that are produced by the invention can
comprise a lower oil content than food products subjected to known immersion
frying
processes. Generally, the method described herein can be used to control oil
content so that
the final oil content is similar to conventionally fried potato slices, or in
another embodiment,
lower than conventionally fried potato slices. In one embodiment, potato
slices produced by
the inventive method comprise an oil content of about 30%, whereas potato
slices produced
using only a conventional immersion frying step would comprise an oil content
of about
35%. This result was surprising because the inventive fried food products also
have flavor,
color and texture characteristics similar to fried food products produced by
known frying
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methods. Even though the invention is not limited by theory, Applicants
believe that the hot
oil finish frying step controls oil content in several ways.
[0031] The viscosity of frying oil generally decreases with increasing
temperature.
Applicants believe that the hotter oil used in the finish frying step of the
present invention
drains more efficiently from the slices on the takeout conveyor.
[0032] The hot oil also likely causes a rapid increase in chip temperature
which
converts most of the water remaining inside the potato slices into steam,
which exits the
slices. Applicants believe that this rapid conversion to steam also ejects a
portion of the oil
that had been absorbed into the slice during immersion frying. In fact, when
Applicants have
analyzed the location of oil inside and on the surface of potato chips fried
according to
conventional methods, and compared it with those fried according to the
inventive method
described herein, Applicants have found a striking difference in the location
of oil that is
believed to confer advantages over prior art potato chips. Applicants tested a
range of potato
chips, from samples that are commercially available and samples fried under
process
laboratory conditions according to previously known methods, to samples made
according to
the inventive method described herein. The inventive potato chips have been
found to
comprise more oil near the outer surfaces as compared to the interior of the
chip, than known
prior art slices.
[0033] To perform the oil location analysis, Applicants performed a CT
(computed
tomography) scan on the known and inventive samples of potato chips. Each
sample was
prepared for CT scan by first selecting a source for the sample. Commercially
available
samples included potato chips sold under the trademarks Lay's Classic,
Walkers, Walkers
Light, Reduced Fat Ruffles, and Lay's Light. The commercially available
reduced fat potato
chips analyzed here were made by conventionally frying potato slices and
mechanically
stripping oil from the chips (typically by passing high velocity air or steam
over them) after
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they were removed from the hot oil frying step. Inventive potato chips
included samples
fried at varying conditions to produce total oil content by weight that ranged
from
approximately equal to Lay's Classic to approximately equal to the
commercially available
reduced fat potato chips described above.
[0034] From each sample, a relatively flat potato chip was chosen, and that
chip
was broken into an approximately square piece that was about 2 centimeters on
a side. The
2cm square piece was then glued to a specimen holder and placed into the CT
scanner, and
the resulting image color coded for density. The CT scanner was a Sky-scan
1172 computed
tomography x-ray scanner, and the Sky-scan 1172 software was used to develop
the raw
images. The scanner settings were as follows: medium camera pixels ¨ 2K; pixel
size ¨ 5-7
um; rotation separation ¨ 0.3 degrees; averaging ¨ 7 frames; random movement ¨
5. The raw
images were also reconstructed using NRecon software. Image analysis was
performed using
CTAn and CTVol software, and Microsoft Excel. When the images are color coded
for
density, the oil and potato starch appear as distinct colors, and the CT
scanner software can
determine the total volume and percent volume of each component. The data for
each slice
was divided into volumetric thirds, with each volumetric third consisting of
(2cm)x(2cm)x(1/3 slice thickness). In other words, each outer third comprised
one of the two
4-square-centimeter outer surfaces of the sample piece, and the inner third
did not include
either 4-square-centimeter outer surface of the sample piece. The data was
then analyzed by
computer algorithm to determine how much oil was contained in each third of
the slice. For
each sample, more oil was found in the outer thirds than the inner third.
However, the
inventive potato slices comprised surprisingly more oil in the outer thirds
than the inner third.
[0035] The oil distribution between the interior and exterior of a potato
slice can be
quantified by subtracting the oil content in the middle third from the average
of the oil
contents in the outer thirds, dividing that by the average of the oil contents
of the outer thirds.
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As used herein, the term Surface Oil Difference for a potato chip shall be
defined as
((average of oil contents of outer thirds) minus (oil content of inner third))
divided by
(average of oil contents of outer thirds). All oil contents used in the
Surface Oil Difference
calculation are measured as a percentage of total oil volume, as determined
using the CT
scanning procedure and method described above. In other words, one inventive
sample
comprised 40.5% of the total oil volume in one outer third, 46% of the total
oil volume in the
other outer third, and 13.5% of the total oil volume in the interior third.
For all samples
tested, the Surface Oil Difference ranged from about 0.15 to about 0.7. The
low oil varieties
sold under the trademarks Walkers Light, Reduced Fat Ruffles, and Lay's Light
exhibited a
Surface Oil Difference of 0.15 to 0.25. Lay's Classic had a Surface Oil
Difference of 0.45.
Four separate samples of the inventive potato chips described herein exhibited
a Surface Oil
Difference above 0.5, ranging from 0.52 to 0.69. Therefore, in one embodiment,
the
inventive potato chip herein comprises a Surface Oil Difference of 0.5 or
greater, or in
another embodiment a Surface Oil Difference between 0.5 and 0.7.
[0036] Applicants also theorized that because the potato slices that become
the
inventive potato chips have undergone a different thermal history than prior
art or known
potato slices, the potato starch of the final product may also exhibit
different characteristics
than that of known potato chips. In fact, Applicants have found that the
potato starch of the
inventive chips does exhibit a unique RVA (rapid visco analyzer) curve as
compared to
known or commercially available potato chips. To analyze this starch property,
Applicants
prepared the potato chip samples for RVA analysis as follows: the potato chip
samples were
chopped into fine particles, and the residual frying oil was extracted from
each sample using
a Buchi Soxhlet Extraction Unit B-811. Defatting the potato chip samples
focuses the
analysis on the potato starch by substantially eliminating any influence on
RVA results due to
different oil content between samples.
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[0037] Next, three grams of defatted potato chip sample and 25 grams of water
are
mixed in an RVA container, and immediately inserted into the RVA machine. The
starting
temperature for the RVA analysis was 30 C. The RVA paddle spins at 960rpm for
the first
seconds of the analysis, then 1601pm for the remainder. The temperature
remains at 30 C
for the first three minutes of the analysis, then is raised 95 C over the next
seven minutes,
remains at 95 C for the next four minutes, drops to 50 C over the following
four minutes,
and remains at 50 C for the final minute of the test. The total time for the
analysis is 19
minutes. The sample preparation and RVA analysis protocol described above will
be referred
to herein as the "RVA Protocol" and for claims directed to potato chips having
certain RVA
characteristics, such RVA characteristics are intended to be measured using
the RVA
protocol.
[0038] The resulting RVA curves are depicted in Figure 4. Each inventive
potato
chip curve 402 and 404, comprises a first peak 412 and 410, and a second peak
416 and 414,
respectively. When the quantity (peak 2/peak 1) is plotted on the y-axis
versus (peak 1) on
the x-axis, the inventive potato chips occupy a region of the graph that is
uninhabited by data
points for the other samples tested. In particular, for all of the inventive
samples analyzed by
Applicants, the (peak 2/peak 1) value of the RVA curve is between 0.25 and
0.45, and peak 1
value of the RVA curve is between 6000 and 8100. The data points for all other
tested
samples fell outside these ranges. Therefore, in one embodiment, the potato
chips of the
present invention comprise a first RVA peak and a second RVA peak, wherein
(second RVA
peak/first RVA peak) is between 0.25 and 0.45, and wherein said first RVA peak
is between
6000 and 8100.
[0039] The oil location and RVA differences between the known and inventive
slices are particularly surprising in light of the results of an analysis
performed by a trained
sensory panel on known and inventive potato chips. A panel of sensory analysts
specifically
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trained to define and describe differences between a reference potato chip and
test potato
chips was asked to evaluate several different potato chip samples in
comparison to the
reference, including inventive potato chips comprising 35% oil, 33% oil, and
28% oil, along
with two commercially available Lay's potato chip samples at 35% and 38% oil,
two
commercially available low oil potato chips produced by mechanical stripping
of oil post-
frying, and two conventional potato chip samples at 35% and 36% oil made
according to
known frying methods in a process lab. The sensory panel rated the inventive
samples at
33% and 35% oil as slightly different and very slightly different,
respectively, from the
reference sample. The 28% oil inventive potato chip sample was rated as
definitely different,
but less different than either of the commercially available low oil samples.
However, the
main driver of the difference in the 28% oil sample was an off-flavor in the
oil. The texture
ratings given for all inventive samples compared favorably to the reference
sample. The fact
that slightly lower oil inventive samples were perceived as very slightly
different or slightly
different may be explained by the presence of more oil at the surface of those
chips, as
compared to the oil found near the middle of the chips. Oil near the surface
is available to be
immediately perceived when the chips are eaten. Even the very low oil
inventive potato chip
would likely have been perceived as slightly or very slightly different from
reference if the
oil flavor itself had not been described as off.
[0040] Applicants have observed that when typical potato slices are fried
using
previous immersion frying methods, after a residence time in the oil of
between about 80
seconds and 130 seconds, the bubbling of potato slices inside the fryer slows
substantially ¨ a
point referred to as the bubble end point. The bubble end point will vary
according to potato
slice characteristics and oil temperature, but regardless of conditions the
bubble end point is
visually perceptible by a skilled artisan. Applicants believe that at this
point, the remaining
water inside the potato slices has stopped converting to steam as efficiently
as before, and oil
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starts absorbing into the potato slices after the bubble end point. As
described herein, in one
embodiment Applicants propose to remove the potato slices from the first
frying step before
or shortly after the bubble end point, and subject them to a short time/higher
temperature
finish frying step to remove the remaining water and reduce the oil content of
the final
product. In one embodiment, the potato slices are removed from the first
frying step within
about 10 seconds of (before or after) the bubble end point. In another
embodiment, the potato
slices are removed from the first frying step less than about 50 seconds after
the bubble end
point, and in a preferred embodiment less than about 30 seconds after the
bubble end point.
Applicants have found that when the potato slices are then transferred to a
hotter oil finish
frying step. the potato slices bubble rapidly as the water remaining in the
slices is converted
to steam. Also, because the food pieces are kept hot during the second frying
step, water
vapor present inside the potato chip will remain in the vapor state for a
longer period of time
and resist oil uptake that is believe to occur during cooling.
[0041] Second, the equipment used to carry out the inventive method can be
easily
retrofitted onto existing frying equipment. Equipment that can be retrofitted
reduces the
capital costs of implementing the inventive method. Perhaps more importantly,
the inventive
method can dramatically increase the capacity and throughput of existing
frying equipment.
As stated above, the immersion frying time for potato chips can be reduced
from about 190
seconds to between 80 and 130 seconds (preferably, between about 100-120
seconds). Such
a reduced frying time could allow an existing fryer that has the capacity to
produce 6,000
pounds of fried food pieces per hour, when modified according to the present
invention, to
produce up to 10,000 pounds per hour of fried food pieces. Because the food
products spend
less time in the frying oil, and because the fryer has increased throughput,
the quality of the
oil will be consistently higher because of the lower duty cycle and
potentially higher fresh oil
replenishment rate. Finally, the inventive potato chips that are produced at
higher capacity
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show similar texture and flavor characteristics to reference and commercially
available potato
chips, but when examined analytically show different oil locations and RVA
curves for the
potato starch.
[0042] It will now be evident to those skilled in the art that there has been
described
herein a method and system that can be used to produce potato chips that have
controlled oil
content but retain the desirable characteristics of conventionally fried food
pieces. Although
the invention hereof has been described by way of a preferred embodiment, it
will be evident
that other adaptations and modifications can be employed without departing
from the spirit
and scope thereof. The terms and expressions employed herein have been used as
terms of
description and not of limitation; and thus, there is no intent of excluding
equivalents, but on
the contrary it is intended to cover any and all equivalents that may be
employed without
departing from the spirit and scope of the invention.
[0043] In sum, while this invention has been particularly shown and described
with
reference to a preferred embodiment, it will be understood by those skilled in
the art that
various changes, in form and detail may be made therein without departing from
the spirit
and scope of the invention.
17
