Note: Descriptions are shown in the official language in which they were submitted.
2 1 85527
--1--
TITLE ~; 7 MULTI-DECK ~r~M~ ET~r~ COOK ANn ~TA~ING RTr-T
FOR pAIr~TQGT~NTC RT.ST~ MANAf-'T'MT~NT pE~n~Ti~.CS
TE('TlNIrAr. FTT~T.I)
The present invention is directed toward a method
and apparatus for transferring heat to food articles
utilizing low temperatures by circulating heat transfer
fluid through thin plates in a narrow controlled
lO temperature range for cooking, thawing, and/or holding
cooked food articles at a precise internal temperature of
+l C, (+2'F) for prolonged time periods.
The cook and staging grill apparatus provides a
precise, uniform thermalizing process provides a means of
15 holding the patties and/or other food articles (which may
be encased in suitable plastic packages) for prolonged
time periods at an equilibrated, safe internal
temperature range, selectable between 54 C and 85 C,
(130-F and 185'F), in order to provide bacteriological
food safety by achieving 99 . 999% thermal lethality of
trace pathogens potentially present in ground meat
articles such as beef or chicken patties.
RA~ K~-.ROUNn OF TT~T INVENTIoN
The present invention relates to a process, a method
of, and -an appar~atus for .transferring heat to food
artic~ .and, more particularly, to a novel process,
method of and apparatus for such purpose, that are
30 particularly adapted for either cooking from frozen or
fresh state or for holding previously cooked food
articles, equilibrated to a preferred, pathogenically
safe internal temperature for prolonged time periods, and
which can also be employed to initially cook food
35 articles or to complete the cooking cycle for food
articles that have previously been partially cooked, or
are fresh-frozen and packaged for cooking in a plastic
~MENDED SIIEET
~ wo95n8ll6 21 8 ~ 527 r ~ 166
--2--
pouch, hermetically sealed and relatively free of oxygen
for extension of the food article's shelf llfe in frozen
format for periods of up to one year.
The multi-deck rl ilr~l 1 cooking and staging grill
5 o~ the present invention utilizes conduction and
radiation heat transf er dynamics relevant to low-
t~ ~UL~ cooking and staging of non-cured meats,
particularly ground red meats such as ~~ ~eL beef
patties . I~sehQriChia eoli 0157 :~7 and other ~.~U1O4e11iC
lO risks are reflected herein as a food safety risk
l~lal.a., ~ process and the a2J2.aL~,Lu~ to consistently and
repetitiously achieve it.
In regard to retail mass feeding of commercial-
level, grilled 1- y~:r ~2Ludu~;~2. ~ the bacteriological
lS and pathogenic food safety, color, moisture content, and
texture uniformity of the product is of primary concern
to the ultimate Cu112i, . The physical characteristics
reflect the reference point of quality 2~an~
associated with this commodity meat product. ~ ~2I
20 products which are cooked by high-heat, high-speed
grilling 2JL~,~.e~2,e~ are subject to considerable moisture
weight losses during any cooking-grilling ~Loces2,es, and
require stringent bacteriological safety monitoring.
It must be understood that the energy of heât ~i.e.,
25 Btu's) can be transferred to any respective product by
many different means, yet the key issue is always
directly related to the optimum "efficiency factor"
associated with any heat transfer proG~qq~n~ technique,
in this case from a heat source to a food article. The
30 mass production of grilled h2 y~r 2~Lodu~;~2~ in the fast
food service industry is presently accomplished via
several conventionally practiced methods, such as the
open grill or flame grill, both high-t~ ~tUL~ grills
llt2 1; ~3 extensively worldwide each of which is either
35 electrically or gas-fired.
Conventionally practiced grilling 2~JLoceduL,2s rely on
the heat transfer by enn~ tion from a heated grill
21 85527
-3 -
surf~ to the respective food article. From a
t~rhn~ly descriptive, factual point of view, any plate
surface-that can be heated by whatever means (e.~.,
electrical, gas or circulated liquid heat transfer media)
is considered to be rightfully designated as a "grill, "
irrespective of any specific operational surface
temperature achievable by various temperature control
means. In slmple terms, any plate that can be heated to
and controlled at an operationally safe temperature can
legally be designated as a grill surface plate. Even a
cold plate is considered a grill, if the plate is
equipped with heating means to achieve a rise in grill
surface temperature capable of achieving thereby a
desired temperature transfer via a specific process
objective to a food article, based on a specific time-
temperature heat transf er curve .
The desired internal product temperature
achievement, from either frozen or refrigerated food
product state, depends therefore on the time span of the
food article's exposure to the time span required to
achieve a desired internal product temperature. This
process, conventionally practiced, has been proven over
many years of practice to steadily fail in guaranteeing
the consistent, dependably reproducible achievement of a
precise internal product temperature within the narrow
range of $1C, (+2 F), in the millions of product
gril~cycles performed daily throughout the industry
on a ~wide basis .
Thermal lethality (i.e., destruction) of pathogenic
bacteria such as Escherichia coli 0157:H7 to a safety
factor of 99 . 999% requires a precise time-temperature
relationship, which must be consistently achieved with
absolute perfection millions of times per day. The
cross-sectional color profile of an uncured, cooked meat
product, however, is, a function of temperature alone --
time is an irrelevant f actor . The cross-sectional
"color" of a cooked meat patty (i.e., a grilled
~MEIIiDED SH~ET
--4--
hamb~), therefore, is a function of the ultimate
inte~product temperature reached and maintained for
the sta~ng (i.e., holding) period. We d LL~te that
the hemoglobin present in red meat is sensitive to color
5 development only with respect to precise internal product
temperature, and is theref ore not dependent upon any
certain of length of time during which the hamburger
patty is exposed to precisely controlled (to within the
narrow range of tl C , ( t2 F ), at temperature variances
from 65C to 74 C, (150 F to 165 F), internal or external
product temperatures commonly practiced in conventional
cooking, grilling and staging processes.
It i8 therefore physically impossible to evaluate a
cooked food product by its color and ensure that
15 conventionally cooked (i.e., grilled) fast food
hamburgers achieve exact, pathogenically safe, optimum
internal temperatures within specific time spans due to
uncontrollable hot and cold spots which are inherent
shortcomings of conventional grills. Restaurants
20 currently cook (i.e., grill) hamburgers, and then usually
store ( i . e ., "hold" or "stage" ) them temporarily in
various, high moisture-generating heating units developed
by the industry for that function. The quality of
products staged in such equipment deteriorates rapidly,
25 due to degradation of the product in terms of moisture
loss, declining flavor intensity, cosmetic appearance and
_,~, ~eel, " and, most importantly, uncontrollable
path~c risk ~anagement affecting the food product's
saf ety f or consumption and resulting in an
30 organoleptically stewed" meat profile.
The lower an end internal product temperature factor
is achieved, the lighter the pink color will be
maintained in the ground meat product's cross-section.
Conversely, the higher the internal temperature of the
35 product is elevated, the darker the meat patty's color
will develop until, in due time, the product's cross-
section turns grayish brown in color at the point of full
AM~NDED SHFT
~ 2 1 85527
--5--
don~ in the range of 68 F to 74 C, (155 F to 165 F).
~e scientif ically verif ied regulations were
published by the USDA and FDA in the Federal Register in
1993, specifying mandatory guidelines and establishing a
5 standard, precise time-temperature relationship f or
thermal lethality of pathogenic organisms in uncured
ground meat patties for the industry to implement and
practice, it became evident that in practice, under "real
world" conditions, these objectives and regulations
10 cannot be consistently achieved via conventional grilling
equipment and procedures as currently practiced in the
industry worldwide.
Until quite recently (prior to 1991) thermal
lethality (i.e., "thermal kill") directives for dangerous ~ -
15 pathogens in food articles, pllhl ich~-l by the U.S. 3,
Department of Agriculture [hereinafter "USDA" ], required
that a ground beef patty be thermalized (i.e., cooked) on
a grill to an internal temperature of at least 63 C,
(145-F), and then maintained at a 63 C, (145 F), internal
20 temperature for staging (i.e., "holding hot" storage).
Due to the subsequent discovery of increased heat
resistance of lethal pathogens in food products, as
revealed during ongoing, extensive research by the
federal authorities to clearly identify public health
25 hazards, in 1993 the USDA and the U.S. Food and Drug
Adminlstration [hereinafter "FDA"] dramatically increased
thei3~rectives' internal food cooking temperature
mand~ in order to assure public food safety in
accordance with the time- and temperature-related cooking
30 requirements represented by Table I and Table II, and
mandated into compliance law as published in the Federal
Register.
Table I shows the Time-Temperature Cooking
Requirements As Mandated by the USDA prior To 1991~ The
35 data for Table I is shown for the time/temperature
combination for cooked ground beef, cooked beef, roast
beef, and cooked corned beef as follows:
~MEliDED SHEET
2 1 85527
= _ - 6 -
TA~E I
Minimum processing time in
Minimum ;nt~rn;~l temperature minutes after minimum
(Degrees) temperature is reached
54.4C (130F) 121
55.0C (131F) 97
55 . 6C (132F) 77
56.1C (133F) 62
56.7C (134F) 47
57.2C (135F) 37
57.8C (136F) 32
58.3C (137F) 2~
58.9C (138F) 19
59.4C (139F) 15
60.0C (140F) 12
60.6C (141F) 10
61.1C (142F) 8
61~ (143F) 6
6~ (144Fj 5
6~ (145F) Instantly
l~MENDED SltE~T
21 85527
~-. ... . .
~ 7 --
Table II shows the Time-Temperature Cookin
Re~uirements As published by the USDA in 1993. The data
for Table II is also shown for the time/temperature
combination for cooked beef, roa3t beef, and cooked
ground beef as follows:
TA3LE I I
Minimum processing time af ter
Minimum internal temperature minimum temperature i8 reached:
( Degrees ) ( Seconds )
66.1C (151F) 41
66.7C (152F) 32
67.2C (153F) 26
67.8C (154F) 20
68.3C (155F) 16
68 . 9C (156F) 13
69.4C (157F) 10
70 . 0C (158F) 7
70.6C (159F) 4
7}~C (160F)
.. ~.
Ah;~NDED S~EET
-8- 2185527
~ d on these recently recognized facts the issue
of pl~q3ie and repetitiously consistent, internal product
tempera~ure control, in relation to product staging
(i.e., holding) time, becomes the single most critical
5 factor in the attempt to provide both bacteriological
~i.e., pathogenic) product safety, as well as a
consistently high level of end product first quality
attributes, which are dependent on the maximum retention
of moisture in the meat patty, by which organoleptic
10 product quality attributes are subconsciously measured
for reference by the consuming public.
Thus, regardless of the specific cooking (i.e.,
grilling) technology deployed in processing hamburger
products, via either :conduction heat, convection heat or
15 steam heat, also known as "wet cooking, " the precise and
consistent internal product temperature control factor,
to be attained and maintained according to USDA
regulations in each beef patty unit irrespective of
minute, individual weight variances existing in the total
20 batch, is the single most critical quality control factor
affecting the food safety, optimum yield (i.e., moisture
retention) and uniform doneness specifications of the end
product, replicable millions of times per day absent any
reliance on human judgment and without the danger of
25 potential human error jeopardizing food safety.
For instance, U.S. Patent 5,247,874 discloses a
gri~,~ c.ratus for high volume commercial cooking
util~ hot oil at a temperature of from between
215.5 C to 232.2 C, (420 F to 450 F), circulating through
30 an upper and lower heating platen hingedly connected
together whereby the high temperatures sear the raw
hamburger meat in direct contact with the platen heating
surfaces sealing in the juices. Moreover, UK Patent
reference GB-A-2220348 discloses a 7 ATn~hl 1 type grill
35 utilizing a pair of electrically heated hinged platens to
cook raw hamburger meat thereinbetween.
AtAEl~DED SitEEI
2185527
-8b-
~entional cooking technology teaches cooking raw
meat~ucts~ directly on a grill surface and subjecting
the meat product to grilling temperatures which are
higher than the ultimately desired internal product
temperature of 68 C to 52 C, (155 F to 165 F) which are
utilized during a cook cycle. Regardless of the specific
grilling heat source, the desired internal product
temperature of each individual beef patty will be reached
at time and temperature variations directly related to
differences in unit weight, mass, and moisture and fat
percentages. Consequently patties with relatively lower
single-unit weights, when exposed to elevated grill
temperatures ranging from 176.5 C up to 218 C, (350 F up
to 425 F), depending on the cookin~ methodology utilized,
will attain higher internal temperatures within the same
given
A~ttEl~ÇD SHEET
21 85527
g
time~ than will those patties with greater unit
weig~ ~
Irls emphasized that precise control of individual
unit weight f actors in mass produced, ground meat
patties, to within a variance of less than +0.01 to
0 . 0125 grams per single product unit, is economically
unfeasible. Any attempt to further narrow this weight
tolerance per single ground meat patty unit is not
justified, as such would increase the product's end price
on the marketplace above a competitive "commodity" level.
Consequently, the only option available to precisely
control the internal temperatures o~ individual ground
meat patty product cooked (i.e., grilled), in small or
large batches, irrespective of their variable single unit
product weight factors, is by exposure of the total
volume of products to a conduction heat transfer
environment maintained precisely at, and not higher than,
the end temperature desired as the ultimate internal
product temperature f or the entire batch . Under these
conditions all single patties, regardless of their
variable unit weights, will ultimately equilibrate at an
identical internal product temperature, within the narrow
range of tO.5 C, (+1 F), within a given time span,
thereby meeting all USDA regulations related to time-
temperature exposure and consequently providing
bacteriological safety and optimum end product quality
attri~gx .
- - ~, the product unit with the least unit weight
- fact~,ll reach a given internal temperature of, as an
example, 65.5 C, (150 F), if exposed to a conduction
temperature of 65.5 C, (150 F), for a time factor of X;
where units with greater unit weight factors will
ultimately attain the identical internal temperature with
a time factor of X + Y, while the smaller product unit is
~;imultaneously maintained (i.e., held) at the ultimate
temperature during the time span required for larger
product units to reach optimum internal temperature as
specified in the USDA's mandatory regulations.
A~ENDED SH~ET
~ 2185527
--10--
~ingle grilled product unit, however, regardless
of i~ariable individual weight factor, will ever
attain~-a higher equilibrated internal temperature than
the conduction temperature to which the full batch is
exposed, in the above example 65.6C, (150-F). Bearing
in mind the objective of such precise internal
temperature control over products varying in their
respective unit weights, the time span utilized to
equilibrate and hold is therefore dependent on the
10 specific grill surface conduction temperature exposure,
and demonstrates the consistent achievement of control
over the most critical point of reference of the process
and apparatus.
Conventional methods for temporary storage or
15 staging of hamburger patties in high-humidity
environments for prolonged time spans does affect the
product ' s opt imum y i e l d ( i . e ., mo i s ture content ),
tenderness and myosin bond structure, thereby influencing
the patties ' organoleptic attributes as well as their
20 perceived "bite-feel. "
The multi-deck clamshell, low-temperature conduction
and radiation, cooking and staging grill of the present
invention may be used as a means of thawing precooked,
frozen meat patties, cooking fresh-frozen meat patties,
25 or staging for equilibration ~.ILI~oses, with the advantage
of fully grilled patties consistently achieving
equil~rated internal product temperatures varying
betw~2.8-C and 74C, (145F and 165-F), within the
naL,,~5,~olectable temperature range of +0.5 C, (+1 F).
30 The meat product processed thereby retains a
signif icantly higher moisture content than during the
high-speed elevation of internal product temperature by
conduction through exposure to surface grill temperatures
ranging from 176.5 C up to 218 C, (350 F up to 425 F).
35 The multi-deck cooking and staging grill is designed for
maintaining internal product temperature equilibration to
a final, pathogenically safe temperature, requiring only
that the sum total of all products exposed to the
equilibration process in the staging grill to achieve a
AN~I'IDED SHEET
-11- 2 1 85527
t~ ~yLe equilibxation balance between 0.5 C and
7.8 ~ F and 15 F). A maximum temperature elevation
of onl~5 C to 7.8 C, (10 F to 15 F), is needed to raise
all individual food articles to the ideal internal
5 temperature when these products have been either fully
cooked on an open grill or a clamshell grill at high
speeds, for between 90 and 240 seconds, as practiced
universally by the industry with high-speed, high-
temperature grills.
Based on the above-described critical factors
associated with the mass production of grilled ground
beef (i.e., hamburger) products, the optimum risk
management via the low-temperature clamshell cooking and
staging grill technology offers the most precise and
15 efficient heat transfer dynamics capable of consistently
providing the bacteriological (i.e., pathogenic food)
safety, color uniformity, moisture retention and highest
organoleptic quality attributes in the mass production of
this food article, all benefiting the perfection of
20 state-of-the-art technical performance achievements for
providing first quality food which is impossible to
attain with conventionally known and practiced grilling
technologies .
Ground red meats which are neither in]ected nor
25 marinated with curing agents of any type, such as
nitrites, nitrates, salts, phosphates or other formulated
curi~Lgents, may be subjected to various internal
prod~c~rprature elevation procedures resulting in
rl~ci~;doneness levels (i.e., cross-sectional- color
30 intensity, from bloody pink to grayish brown), ranging
from 54.4 C to 73.9 C, (130 F to 165 F), in t~ a~uLe
exposure. The meats are then held at a selected, precise
temperature for various staging time spans in accordance
with stringent USDA regulations ~p~n~11 n~ strictly on
35 exposure to their specific temperature factors for
desired, uniform cross-sectional color profile
development. Contrary to conventional grilling
processes, the actual staging (i.e., holding)
time factor, ;~t an equi1ibrating
AMENDED S~IEET
21 8552~
--12--
t~ LÇ from- 65.6 C to 73.9 C, (150 F to 165 F), is
ther~ irrelevant in determining the cross-sectional
meat color profile.
The preferred ` -~;r-~lt of the multi-deck, low-
5 temperature conduction and radiation, high-speed cooking
and staging grill comprises at least one and preferably
a plurality of horizontally hinged, layered, and
interlocking trays forming "decks" in a clamshell
arrangement. Each tray, or plate, comprises a first and
10 second sheet, having a serpentine fluid heat transfer
passage formed thereinbetween for recirculation of a heat
transfer media. The recirculated heat transfer media and
the surface of the plates are precision-controlled within
the narrow range of +l C, (+2 F), at selected "low"
temperatures up to 96 C, ~205 F), or higher when
temperatures up to 260 C, (500 F) are desirable. The
trays are designed to effect uniform, low-temperature
conduction and radiation heat transfer to the center of
each patty or other food article. A computerized,
electronic control system directs and monitors the
process, and records the time and temperature variables,
as well as ultimate internal product temperature
equilibration, for the multi-deck cooking and staging
grill .
The multi-deck cooking and staging grill, in either
single-, double- or multi-deck format, will provide
equi~r,~Lted temperatures for any selected conductive
gril~-face within the center of each ground beef patty
with~be precision of +0.5 C, (+l F), irrespective of
the position of the patty on the grill plate, or weight,
thickness or circumference variables of a wide variety of
meet patties. Once a single hamburger (or multitude of
patties) is placed in the grill's trays, and clamped
between two conductive grill plates from the top and
bottom, the equilibration temperature selected to effect
thermal kill of trace pathogens will be maintained for a
minimum time span, as mandated by federal regulations to
be sufficient to kill any pathogenic bacteria, before the
tray can be opened and the product served. A
~MENDED S~IEET
-13- 2 ~ 85527
7ed electronic process monitoring means signals
(bot~5ibly and visually) when a tray of hamburgers is
available for dispensing and safe consumption, thereby
meeting USDA- and FDA-mandated pathogenic thermal
5 lethality requirements for cooked food articles.
Furthermore, the multi-deck cl ~Ch~l 1 cooking and
staging grill is designed to incorporate interlocking,
stacked trays in various shapes and sizes, formed as to
depth into a "pan" means, wherein the bottom, deep-drawn
10 "pan tray" is constantly heated by conduction, via the
hot, circulating heat transfer fluid, thereby cooking and
"holding hot" any food product that is maintained in unit
form or in bulk, in an absolutely safe and perfect
temperature environment between 71 C and 96 C, (160 F and
15 205 F), depending on the specific ideal, or preferred,
temperature of any specified food article. The heated,
"deep pan tray" is covered with the bottom of a heated
plate, positioned above the heated deep pan tray, thereby
forming a "lid" means which can be elevated to offer easy
20 removal of a product from the lower deep pan tray for hot
food serving purposes at high speeds, and instant lid
closure for maximum uniform heat retention of the stored
hot f ood in the bottom pan .
All vertical, perpendicular and horizontal, fluid-
25 connected vessels will be connectable and disconnectablefrom the recirculating liquid heat transfer hot media
supp~a standard, quick-~l;crnnnect means, which are
avai~i for thi~s application from several nanufacturing
sources. The same process principle can be practiced in
30 a variety of shapes and apparatus configurations such as
double-walled vessels for maintenance of hot soups,
coffee, tea, and other foods constituting liquid and
solid food substances.
The method and apparatus described herein f or the
35 multi-deck, conduction and radiation, clamshell cooking
and staging grill and processing procedures have a
significant impact on the quality of the cooked, hot food
AME~DED SHEET
21 85527
--14--
pro~ ring prolonged staging, due to the fact that
any p~ct subjected to this unique staging (i.e., hot
holdingr~ procedure will have a dramatic, time-related
quality and food safety elasticity by at least lOO to 300
5 or more percent longer, due to its higher moisture
content retention achieved by the precision
equilibration, internal and external food article
temperature control and the environment in which the food
is stored, by convective, conductive and radiation
10 equilibration within the narrow range of +1 C, (+2 F),
for hours of safe maintenance, without generating any
excessive water vapor (i.e., moisture evacuation) from
the hot-held food article of protein or farinaceous
composition .
The net result is not only addressing the
achievement of bacteriological and pathogenic food
safety, but highlighting the retention of the delicate,
volatile, "seared" flavor components achieved during the
preliminary, high-temperature grilling process, and by
20 avoiding the subjection of previously grilled food
products to a high-moisture (i.e., saturated) environment
in secondary staging which will, by rapid oxidation,
negatively quench and dissipate the delicate aromatic and
flavor components and preferred attributes achieved with
25 high-temperature grilling, which are organoleptic quality
attr~u~es most desired by the consuming public.
- -
~: Su~lMARY OF THE INVENTION
The present invention comprises a double-, triple-
30 or multi-deck conduction and radiation cooking and
staging grill for pathogenic risk management of food
articles, constructed of interlocking trays or heat
transfer plates spaced apart from one another and formed
from at least two sheets of material having heat transfer
35 fluid circulating therethrough. The specially designed
heat transfer plate configuration may utilize metal
sheets which are seam- and spot-welded, and high-
AMEI~D SHEET
2 1 85527
--15--
pres~ pillow inflation-expanded, with one side flat
and W~h~ second side slightly pillow-expanded, which
is thè preferred method for utilizing stainless steel
sheets, or the roll-bonded, pillow- or serpentine-
5 expanded aluminum sheets providing two substantially flatsurfaces with liquid heat transfer media passages. The
liquid heat transfer fluid channel is expanded and
designed to allow a maximum liquid heat transfer media
flow rate, evenly distributed through the entire surface
10 of the plate, achieving by their recirculating liquid
transfer r~h;3nn~ the maximum unifo~m and equilibrated
heat transfer across the entire plate grill surface
within the narrow range of +0.5 C, (+l Fl.
The trays or heat exchange plates of the single deck
15 or mult-deck units are hingeably engagable or
disengagable ~rom contact with each other and the
thermalized hot-held product by specifically designed
spacer configurations aligned for nesting or hingably
connecting each of the plates to the housing frame.
20 ~echanical hinging means such as removably secured
horizontal plates are disengaged in parallel, or the
plates are pivotally moveable into vertical position
relative to each other by lever hinges attached to at
least one end of the heat exchange plates and the frame.
25 The hinge means enables the fluid-connected heat exchange
plate~o be perpendicularly opened and maintained in
tand~ vertical position, and re~ nl~d in precise
hori:~l condition relative to each other. The hinging
arrangement and locking - -^h~ni ~m provides maximum
30 conductive heat transfer to the "clamped" food articles,
from the top side as well as from the bottom side of the
grill plates, achieving the most efficient heat transfer
of Btu's by conduction and partial radiation to the
respective food article, namely the hA ' _Ly~:r or chicken
35 patty or any food article designed to be efficiently
thermalized within the space allocation between two or
more heat transfer thermalization plates.
AME'.~DED SHEEr
2 1 85527
--16--
~ igrill plates in their horizontal, thermalization
posi~are slightly slanted toward the back side of the
apparat-Us, so as to cause excess fat drainage from the
hot-held hamburger patties to a fat (i.e., excess grease)
5 retention container provided for that purpose which can
be timely removed and the trapped grease can then be
discarded for ultimate disposal. The lower side of the
grill plate may be provided with round or rectangular
protrusions of 3~16" to 1/4" depth for penetrating into
10 the hamburger patties to secure the patties in vertical
cooking or staging position, thus preventing movement of
the patties when two engaged grill plates are angularly
raised to vertical position for access to a bottom plate
containing a volume of cooked and hot-held h~i~JuLgl L
15 patties for immediate sale to respective customers.
Further, selected ~Yr~n~ie~l protrusions projecting from
the grill plate are provided with a desired raised
insignia or corporate logo for the purpose of indentation
into a hamburger patty by the weight of the upper plate
20 for marketing or promotional opportunities.
A low-temperature, liquid heat transfer medium is
continuously recirculated via a low-pressure, magnetic
centrifugal pump. The lower temperature heat transfer
fluid is supplied from a small reservoir equipped with
25 submerged electrical heater means ranging between 1.5 and
5 kwh ~or higher, if called for), and controlled by
electLo~c, proportionate thermocouple-sensitive, energy
- inpu~ctivating and deactivating means, with
m; 11 ~rl~lc energy input response. The liquid heat
30 transfer medium is controlled at a precise temperature
selected to effect the grill plate surface temperature
within the narrow range of i:1 F. The low-temperature
cooking and staging grill is designed to operate below
the boiling point of 100 C, (212 F), and therefore does
35 not require any atmospheric, pressure-release venting
means .
The low-temperature equilibration cooking grill and
staging apparatus does not cause any excessive water
AME~DED S~IEET
2 1 85527
--17--
vapo~essure in the food product ( i . e., hamburger
patt~ and maintains food articles at a
bacteri~logically safe temperature without any moisture
loss or degradation of the food articles, resulting in
5 perfect quality for prolonged time spans ~ ee~ling 30 to
40 minutes.
Conventional grills and fryers, operating at
temperatures above 100 C, (212 F), (i.e., the boiling
point of water), and many times extending from 162.8 C,
(325 F), up into the 218 C, (425 F), to 260 C, (500 F),
range, are required by law to be equipped with automatic
fire extinguishers, and ventilation hoods provided with
means for filtration of emitted grease vapor fumes. The
low-temperature cooking and staging grill of the present
15 invention generates no objectionable or volatile food
odor~; or grease vapors, and can therefore be operated in
any commercial environment without requiring venting
and/or fire extinguishing means, such as an ancill
system, thus, presenting no objectionable Environmental
20 Protection Agency compliance mandates for public
est~hl i ~h~nts and a cost savings associated with the
incorporation, installation, maintenance and operation of
exhaust equipment. Futhermore, the elimination of
venting and fire extinguishing means is an important
25 consideration in the portability of the stand-alone
cooking and staging grill.
~ ooked hamburger patties can be ef f iciently
re~h ~ i zed from frozen state and held until sales
demand occurs, for prolonged or instant availability.
30 The double-, triple- or quadruple-staggered design of the
grill plates can be designed to meet any required
production schedule cycle, strictly depending on
pro~ected product sales per hour. The low-temperature
cooking and staging grill is user-friendly, non-
35 intimidating and perfectly safe for the operator;therefore, no burn hazards or related injuries are
associated with operation of the apparatus or practice of
AME~DED S~r~T
~ WO 95/28116 2 1 8 5 5 2 7 PCT/US95/05166
--18--
thc ~hDrr- l i 7ation process .
Electronic safety control means are provided so as
to interlock the respective individual plates for a
specific, selected operational sequence time. A
5 computerized in..~- 1 panel monitors and controls the
process of the grill and maintains and digitally displays
precise product f~ aLuLe proCc~6c;n~ records.
Electronic means are mounted on suitable areas of the
plate designed to assure the time-t~ ~UL~: maintenance
10 of a volume of h: ' y~l patties for a predet~rminDd time
at a specific conduction t~ ~lLUL~ required to achieve
the critical thermal lethality curve for any pathogenic
residuals in the patty. The electronic safety control
means are so designed as to interlock two respective
15 plates for a specific, prD~l~DtDrm;n~d time, and will only
release the ~ : of the plates once sufficient
~taging time has elapsed, thereby assuring the pathogenic
risk r~r~ ~ ~, time-temperature equilibration
repetitively providing the food article's safety, in
20 compliance with USDA-mandated thDrr-l; 7~tion ~LUCedULC:S.
Provisions are also inco, ~u. at.ed which will sound an
alarm should a plate be manually 1; c~n~A~ed by an
operator prior to the minimum safe time maintenance
(i.e., "safety dwell time) for completion of the
25 Dqllilihration cycle as specifically required for product
t~, aLu~: equilibration during prolonged staging.
Thus, the rl ~m<~hDl 1 cook and staging grill of the
present invention provides a means for transferring heat
to food articles ~t;1;7;n~ an apparatus comprising a
30 housing frame having a deck therein including at least
one pair of stacked plates comprising a f irst plate and
a second plate spaced apart and in alignment, each plate
comprising a first sheet and a second sheet of heat
transfer material bonded together having fluid heat
35 transfer passages thereinbetween for recirculation of a
heat transfer fluid wherein the plates are mounted to the
housing. The apparatus further includes means for
21 85527
--19--
conn~ely mounting the plates to the housing, a
rese~ within the housing for containing a heat
transfer fluid, means for fluid-connecting the plates
and the reservoir, means for heating the heat transfer
f luid to a selected temperature in the reservoir, means
for controlling the temperature of the heat transfer
fluid within the reservoir at +l C, (+2-F), means for
recirculating the heat transf er f luid through the plates
in f luid-connection with the reservoir and each of the
heat transfer plates, and temperature sensing means for
determining the temperature of at least one of the food
articles supported on the plate.
The present invention provides a method of
pathogenic risk management utilizing a clamshell grill
cooking and staging procQss for transferring heat to food
articles comprising the steps of placing a food article
to be heated between a first plate and a second plate
hingeably mounted to a frame of a cooking and staging
grill, heating the heat transfer fluid to a selected
temperature in the reservoir, fluid-connecting the plates
and the reservoir, controlling the temperature of the
heat transfer fluid within the reservoir at +1 C, (+2 F),
recirculating the heat transfer fluid through the plates
in f luid-connection with the reservoir and each of the
heat transfer plates, and sensing the temperature of the
heating fluid and the food article for controlling the
e thereof.
~s an obiect of the present invention to provide
an apparatus and process having the ability to thaw, cook
and hold a variety of ~r~:kd~d foods at optimum,
pathogenically safe temperatures, for extended periods of
time, without loss of quality and, most importantly,
advancing the most critical aspect of pathogenic food
safety for the mass feeding industries.
It is an object of the present invention to provide
a system for continuously circulating heated fluid
through passage-l~ypAn~l~d metal shelves, providing even
~MENDE~ S~EET
21 85527
--20--
fh~at;on temperatures over the respective plate
surf~within the narrow range of $0.5 C, ($1 F),
therefo~e eliminating any hot or cold spots across the
entire surface of the grill plate.
It is an object of the present invention to provide
a hot-held inventory (i.e., a "bank") of food products to
be held for instant serving, in the safest condition and
at the highest possi~le organoleptic quality level.
It is an object of the present invention to provide
visual gauges, backed by audible and digitally
illuminated, electronic sensing controls for safeguarding
the product and monitoring the process.
It is an object to provide actual and set
temperature indicators easily viewed on digital
electronic displays. A,
It is an object to provide solid-state
microprocessors which maintain tight and consistent
temperature monitoring and narrow-range calibration.
It is an object to provide an apparatus designed and
constructed to meet stringent safety and sanitation
requirements for UL, CSA and NSF approval.
It is an object of the present invention to provide
a multi-deck cl Archr-l 1 cook and staging grill that does
not require venting, and is implementable in any kiosk or
commercial food service operation.
It is an object of the present invention to provide
a m~ k clamshell cook and staging grill which is
port3~- ~
It is an object of the present invention to provide
a staging process for pathogenic risk r~n~ nt suitable
for products thermalized by grilling and/or frying
processes, and then held for staging; or for the
rethermalization of precooked, frozen products to be
dispensed without further treatment.
It is an object to provide an apparatus and
thermalization process to manage the pathogenic risks
associated with the deadly pathogen Escherichia col i
AMENDE~ SHEET
~ WO 95/28116 2 1 8 5 5 2 7 . ~
--21--
0157:~7. and and achieve thermal lethality thereof.
BRIFF L~ OF THE n~
A better understanding of tne present invention will
be had upon reference to the following description in
conjunction with the P' ying drawings in which like
numerals refer to like part6 U1L~U~ UL the several views
and wherein:
Figure 1 is a pel~e~ Live view of showing the
multi-deck cook and staging grill for ~ oge~l-ic risk
.na, L of the present invention having one of the
stacked interlocking trays being open having a heat
transfer conduit shown on the ~ottom thereof and meat
patties being shown in phantom lines on the top of the
ad j acent tray;
Figure 2 is a front view of the multi-deck cook and
staging grill of Figure 1 showing the trays in the closed
position;
Figure 3 is a side view of the multi-deck cook and
staging grill of Figure 1 showing several plates being
closed with the top plate in the open position;
Figure 4 is a cut-away perspective view of the
multi-deck cook and staging grill of Figure 1, showing
some of the Ls within the housing;
Figure 5 is a side view of one of the plates of the
multi-deck cook and staging grill;
Figure 6 is a top view of an: ` ~i t of the
present invention showing an aIL~ll., L of the pump,
reservoir, and heating ele~ents therein;
Figure 7 is a per ,,~eL:Live view of showing an
alternate: I i- L of Figure 1 with one of the stacked
interlocking trays being open, 3nd showing a heat
transfer conduit and meat patties in phantom lines,
- 35 wherein the control panel is mounted upon the rear
portion of the base of the multi-deck cook and staging
grill rather than located in the front portion of the
W095/28116 ' 2 i 8 5 5 2 7 L ~
--22--
baDe as shown in the ~ t of Figure l;
Figure 8 is a front view of the multi-deck cook and
staging grill of Figure 7 showing the trays in the closed
position;
Figure g i6 a p.:LD~e~,Live view of the nulti-deck
cook and staging grill of Figure 7 Snowing the top plate
in the open position and having protuberances extending
from the bottom thereof;
Figure 10 is a side view of the multi-deck cook and
staging grill of Figure 7 showing several plates being
closed with the top plate in the open position;
Figure 11 is a top view of one of an inked sheet
showing dark shaded no-weld inked surfaces and the light
to-be-welded surface areas of a typical roll bonded
panel;
Figure 12 is a top view showing the heat transfer
fluid conduits between the welds of the roll bonded
of the present invention;
Figure 13 is a cross-sectional view of a plate along
lines 13-13 showing the heat transfer fluid conduits of
the double sheet roll bonded panel forming a tray of the
present invention;
Figure 14 is an enlarged view o~ Figure 13;
Figure 15 is a top view of a roll bonded panel
showing a circuit formed having a plurality of conduits
and dirlples f ormed therein;
Figure 16 is a peL,,~e-,Live view showing a stainless
steel tray of the present invention having a quilted
pattern produced by resistance spot and seam welding;
Figure 17 is a perspective view showing a stainles6
steel tray of the present invention having a quilted
serpentine pattern produced by resistance spot and seam
welding;
Figure 18 is a pe~ e~;Live view of a stainless steel
plate of the pre6ent invention produced ~y resistance
welding multiple spot welds at the desired points to
increase the DL~ yLI~ of the plate increase the heat
2 1 85527
--23--
tran =E~between :the.sheets .and the heat transfer liquid
circ~ng therethrough in a free flow pattern;
Fi~ure 19 is a perspective view of a dimple one
sided plate;
Figure 20 is an enlarged front plan view of the
dimple one sided plate shown in Figure 19;
Figure 21 is a perspective view of an inflated one
side plate having a single embossed surface;
Figure 22 is an enlarged front plan view of the
single embossed surface plate shown in Figures 22;
Figure 23 is a perspective view of an inflated both
sides plate having a double: ' -s-.ecl surface;
Figure 24 is an enlarged front plan view of the
inflated doubled.embossed surface plate of Figure 23;
Figure 25 is a deep well tray formed from a
resistant welded plate;
Figure 26 is perspective view of cook and staging
grill of Figure 7, showing plates formed having
depressions for containing food articles therein between
the plates;
Figure 27 is perspective view of the cook and
staging grill of Figure 26, showing smooth plates in
combination with plates formed having depressions for
containing food articles therein between the plates;
Figure 28 is a perspective view of the cook and
staging grill showing heating food articles contained in
seale~ at r--nflllct i nq pouch containers; and
-~re 29 :is. a graph showing the time versus
t~ L~r ~ relationship for heating frozen meat patties
using the present invention.
SPECIFICATION
As illustr~ted in Figures 1-16, the present
multi-deck clamshell cook and staging grill 10 for
pathogenic risk management comprises a housing frame 12
supporting a deck 11 of integral heat transfer and
support plate means 14 hingably mounted, swivelly
connected, or disengagably connected thereto. The deck
11 includes a pair of integral heat transfer and support
A~ENDF~ SHEET
2 1 8~27
--24--
plat~ns 14 of the preferred embodiment defining at
lo~c~ upper and lower tray or plate 14 for hingably
mounting to the housing frame 12 for supporting and
heating food articles 13. Each plate 14 is supported
5 independently by the housing frame 12 and mounted one on
top of the other in a clamshell arrangement. The low-
temperature cook and staging grill 10 is designated to
operate below the boiling point of 100 C, (212 F), and
therefore does not require any atmospheric venting means
10 nor sealing means between the trays or plates 14 when
utilized as a cook and staging grill 10. For cook and
staging grill 10 applications, the low-temperature
equilibrztion grill 10 does not cause any excessive vapor
pressure in the product, i._. hamburger patty, and
15 maintains the food articles 13 at a bacteriologically
safe temperature without any moisture loss or degradation
of the food. However, the plates 14 in the preferred
embodiment are spaced apart from one another and
supported by a nonsealing frame 15 surrounding the
20 periphery of the plate 14 in order to contain food
articles 13 therein between each plate 14 and control the
drainage of liguids formed in the heating process,
wherein the food articles 13 are contiguous with the
bottom surface of a top plate 14 and the top surface of
25 a bottom plate 14. A sealing frame 17 having a sealing
means such as a polymer gasket means l9 may be provided
as an_~ and water tight seal between the plates 14, as
show~i Figure 2, for high temperature cooking
- - app1~n~ above 100 C, ~212 F), in combination with
30 and prior to the staging operations, or for preventing
oxidation of the product due to exposure to the air.
Moreover, the top plate 14 may be coated with an
insulating material to the top surf ace to insulate the
lower plates 14 from ambient temperature conditions and
35 to insulate the user from the heated plates 14 of the
deck ll.
More particularly as shown in Figures 1, 2, and 3,
the housing 12 o~ the preferred F-rhorl;r-nt of the
A,~fE~t~fDEo Sf'ff,~T
2 1 85~27
--25--
clam~$L grill .10 :comprlses a deck 11 of plates 14
~U~ Ey. by a base. 26 having a bottom floor 28 (not
shown)~,~a front side wall 30, a left side wall 32, a
right side wall 34, and a rear side wall 36. An
5 instrument control panel 38 is formed integrally with or
attached to the front of the base 26 as shown in Figure
1 or mounted onto a portion of the housing 12 extending
above the base 26 such as is shown in Figure 7.
As best shown in Figures 4 and 6, the housing
10 contains a reservoir means 16 containing a liquid heat
transfer medium. The sump reservoir 16 is designed to
receive a volume of liquid heat transfer medium, such as
water, or other nontoxic heat transfer liquid. The heat
transfer liquid filled through removable cap is
15 continuously circulated between two or more vertically
staggered manifold connecting conduit means in a volume
sufficient to permit the elevation and maintenance of
specific, equilibrated surface temperatures across the
plate 14 via the temperature-controlled, low-pressure
20 recirculating heat exchange fluid. The reservoir 16 is
fluid-connected to a pump means 20, more particularly a
low-pressure magnetic centrifugal pump 20 driven by an
electric motor 21 f or circulating a low temperature heat
transfer fluid, such as water, oil, or food grade glycol,
25 through the trays 14 which are in fluid communication
with the pump 20 and reservoir 16 through conduit means
22. ~
. : ~ low temperature heat transfer fluid. supplied
from the reservoir 16 is heated by a heating means 18
30 comprising one or more submerged electric heating
elements 18 of sufficient voltage ranging between 1.5 kwh
and 5 kwh and controlled by electronic proportionate
thermocouple-sensitive means to effect a heat surface
density to efficiently transfer BTU's from the heat
35 source to the liquid heat transfer medium continuously
recirculating through the motor-driven, centrifugal
magnetic pump 20. A heating overload safety device is
AMENDE~ S~Er
2 1 85527
--26--
inot-~ted to maintain the heat transfer fluid at a
safe~ating pressure- and temperature. Furthermore, a
fan 2~ -is provided to cool the circulation and process
control equipment.
An electronic, proportionate impulse temperature
controller 44, (not shown), is electronically connected
to the submerged electric heater means 18 and submerged
in the sump reservoir 16 to effect the elevation and
maintenance of the heat transfer medium's temperature by
energizing the heater at required frequencies, thereby
achieving precise control within the narrow range of
+0.5 C, ~+1 F~, over the heat transfer fluid's
temperature. In addition, electrical overrun safety
means are connected to the electric heater in such manner
as to effect safe, instant deactivation of the heater 18,
in case a malfunction of the proportionate temperature
controller 44 should for any reason occur.
The heat transfer medium is controlled at a precise
temperature selected to effect the grill plate 14 surface
temperature. The sump reservoir 16 is also equipped with
electronic means, comprising at least one controller and
at least one thermocouple 42 designed to alternately
activate and deactivate the electric heater 18 at
frequencies required to effect the maintenance of
specific temperatures, within the narrow range of +0.5 C,
(+l F), in the recirculating heat transfer fluid, thereby
provi~ precise surf ace temperature control across the
ent;~te 14. ~ The heat transfer fluid maintains a
con~t~ L~-nr~rature across the surface of each plate 14
connected to the circulation system, within the narrow
range of +1 C, (+2 F), between the heat exchange fluid
entrance and exit ports of the reservoir 16.
The heating and recirculating system supplies the
plates 14 of the multi-deck grill lO with recirculating
heat transfer medium, with BTU input sufficient to
maintain a selected temperature ranging from room
temperature at about lO C. to about 26.7 C,
( 50 F. to about 80 F), to an optional
~,N~)E~ Sl~
2 ~ 85527
; ~
--27--
oper~ temperature of up to 96.1 C, (205 F). Emphasis
is d~ed toward the fact that the fluid-connected,-
recirctrlating assembly is configured, in its totality, as
a closed loop system. The liguid-containing sump
5 reservoir 16 is equipped with a pressure release valve 40
(not shown), or other similar means, in order to allow
the closed loop conf iguration to operate within one to
two atmospheres between the reservoir 16 and system
pressures. The volume of heat transfer fluid is
10 maintained at a constant pressure and velocity throughout
the heat transfer system and control of the temperature
of the heat transfer fluid is effected by a micro-second
controller connected to the electrical heater means 18
and th.o C nuple-sensitive means 42 to obtain the most =~
15 accurate control and quickest response time in order to
achieve and maintain the desired temperature of the fluid
and plates 14 . It is contemplated that the f luid f low
rate parameter could be controlled to control the
temperature of the f luid as well; however, the process
20 control is more complicated, expensive, and usually less
accurate, than by simply controlling the heater means 18.
The double, triple or multi-deck cook and staging
grill lO for pathogenic risk management is constructed of
interlocking trays or heat transfer plates 14 formed from
25 at least two sheets of material having heat transfer
fluid circulating therethrough. In the preferred
embo~t, the:integral heat transfer and support means
14 of~ multi-deck cook and staging grill 10 comprises
at least one and preferably a plurality of horizontal
30 layered interlocking trays or plates 14 spaced apart from
one another in a clamshell arrangement. Each plate 14
consists of a first top sheet 46 and a second bottom
sheet 48 of heat transfer nr)n~ 1 n~ material sealingly
connected together having at least one fluid channel 50
35 thereinbetween, such as a conduit or cavity in fluid
communication with the reservoir 16 through conduit means
such as the hollow tubing 22. Each sheet 46, 48 provides
A~JIENDED S~EEt
~ Wo 95128116 ~ 1 ~3 5 5 2 7 ~"~
--28--
a heat transfer surfnce for conductioin and radiant heat
to the food articles disposed thereon or thereinbetween.
The heat tran6f er f luid and surf ace of the individual
plates 14 are controlled at a selected "low" t~ aLuLa.
5 The trays 14 are ~ ci~nPd to effect rapid and uniform low
temperature heat transfer to the center of each ~ y~L
patty 13.
The trays or plates 14 are hin~PAhly enqageble or
llic~n~agAhle from contact with each other. In the
10 preferred ~ - ir L, the plates 14 supporting the
thc~rr~ hot-held product are mounted by r ~ ' ; ~A 1
hinging means 54 which engage and ~li C~ Age the
horizontal plates 14. More particularly, lever hinges 54
attach to at least one end of the each of the plates 14,
or plate holding frames 15, 17 and the rear wall 36 of
the housing 12 as shown in Figure 3. The hinge means 54
enables the plates 14 to be perp~nAi c~-l Arly opened and
realigned in precise horizontal condition relative to
each other. The hinging arrAn5~ L provides maximum
20 heat transfer fron the plates 14 to the food articles via
rr~ntl~ ti~ and radiation heat transfer from the bottom of
the first top sheet 46 as well as from the top of the
bottom sheet 48 of the grill plates 14. IIOLeUY~:L,
convective ~:ULLallLS formed by moisture present ln the
25 vapors and juices existing in and around the interstices
of the food product also serves to enhance the heat
transfer of BTU's in combination with the conduction and
radiant heat imparted to the food articles from the
plates ~y conduction to the respective food article and
30 convection of moisture formed by juices within the food
article. Typically the food articles are meat ~Ludu- Ls
such as '~ ye:L, turkey, pork, or chicken meat patties
or any other viable food articles 13 inclllain~
vegetables, carbohydrates, and farinAreo~c ~LuduuL~i. A
35 spring means 56, such as a torsion spring may be utilized
to bias each plate 14 in the open "up" position. The
locking latch or fastening means 58 may be utilized to
2 1 85527 ~ 66
095128116
--29--
removably secure each of the plates 14 to the base 26 or
one another in the open "up" position or in the closed
"down" position during the heating cycle. The latches 58
are in electrical , i cation with the control and
5 alarm system 24 and controlled with a ~atlow Process
Controller and Digital Nonitor or equivalent computerized
controller and slarm system 24.
The grill plate 14 can be conf igured to permit a
variety of loading depths (i.e., the distance between the
10 underside of the upper grill plate 14 and the top surface
of the lower grill plate 14. When operational needs call
for a horizontally oriented closing function, the use of
5peri;~1 ly ~l~ci~n~t9~ floating hinges girdling the entire
periphery of the plate and its raised side walls, ( not
15 shown) allow the plate 14 to be lifted from its closed
position by 1/8" up to 4", in the basic configuration, or
even higher when specific purposes necessitate a greater
loading depth. This flexibility in dimensional heights,
achieved through various, operationally specific design
20 modifications, allow5 for Al _ '~tion5 to meet the most
efficient conductive thermalization (i.e., heat transfer)
dynamic as related to the average ~;Luss-se~ Lional
dimensions of any specific food product unit.
The multi-deck rlA~ch~ll grill's 10 offers an
25 additional novel benefit during product fhPrr^l i ~tion
and staging ~L~,ce~~e~. By raising any or all of the
grill's trays 14 from horizontal (i.e., conductive
fh~ l i 7;n~) position to a vertically angled, conductive
th~ i n~ po5ition between from the horizontal plane
30 at about 0 degrees to about 65 degrees, the excess
evacuation of oils and fats extracted from the cooked
food articles, toward the rear of the grill plate 14, i8
effected. A ~:rerjAl1y ~7~cign~7 receptacle basin or fat
retention container 60 is fitted to the rear of each
35 plate to permit ~ 1 Ation of these drippings, and can
easily be removed from the housing 12 for periodic
~7~ CrO5A7 of said fats and oils.
~ 855~7
--30--
. ~W"~:Vt~Lr in the preferred embodiment, the grill
platOE~4 are slanted slightly with respect to the
horizoff~al plane to cause excess fat drainage from the
hot-held h~ ` _Lg~r patties or other food articles 13 to
5 the fat retention container 60 provided for that purpose
for ultimate disposal. It should be noted and is hereby
emphasized that all excess fat and oil fluids, extracted
during the conductive and convective thermalization and
staging processes, do not constitute any volatile fat
10 particles capable of leading to environmental pollution,
since said oil and fat extraction, as well as their
subsequent evacuation, occur at temperatures never higher
than 96.1 C, (205 F), and therefore, always well below
the boiling point of water. Engineering the multiplicity
15 of grill plates 14 within the clamshell qrill 10 so as to t
permit them, in their closed, horizontal orientation, to
be tilted backward at an angle sufficient to cause all
evacuated oil fluids to flow toward the rear receptacle
basin for intermittent accumulation and disposal has
20 distinct organoleptic effects upon previously grilled or
fried food articles 13 via the evacuation of additional
percentages of the fat residues rc--;ninq in precooked
and staged products. Consequently, the end product is
lower in overall fat content (and, hence, more desirable
25 to most consumers) than one not subjected to this unique
staging process.
~ llustrated in Figures 5 and 9, the second bottom
shc~ f the plate 14 may be formed having a multitude
of inflated round or rectangular protrusions 62 of 3~16"
30 to 1/4" in depth for penetrating into the upper or lower
surface of the h~ g~r patties 13 at designated points,
thereby securing the patties 13 in position on the plate
14. This prevents I v L of the patties 13 when two
engaged grill plates 14 are angularly raised for access
35 to a bottom plate 14 containing a volume of cooked and
hot-held hcll~buL~l:L patties 13 for immediate sale to
respective customers. Even when both clamshell grill
AMENDED SI~EEt
~ WO 9S/28116 2 1 8 5 ~ 2 7 f _I/~).., _. . ~ ''
--31--
plat~s 14 are raised from a horizontal orientation to any
angle between about 1 degree and about 60 degrees the
patties 13 Will remain in position. This novel feature
of po6itional maintenance for food articles placed on a
5 grill plate 14 surface, which surface s~lh~eq~ ntly
undergoes .. - ~ ranging from horizontal through a 60
degree angular rise. I~OL~UV~L, the grill ~ L~l.U~ 10
sllrrl;~?~ continuous con~ rtif~n thPrr~l;zation to both
sides of the food article, while simultaneously
10 maintaining its position relative to the grill plate's 14
plane. Furth- -~, tne selected protrusions 62 may be
formed extending outwardly from the bottom second sheet
of the plate 14 with a desired in~;rni~ or cuL~uLa~e logo
64 for indentation into a ~ patty 13 by the
15 weight or spring biasing of the plate 14 as shown in
Figure 9.
The ultra thin high heat transfer trays or plates 14
forming the deck 11 of the multi-deck rl: ' ~11 coolc and
staging grill 10 may be formed as integral heat transfer
20 and support means by several manufacturing t~rhni
such as by roll-bonding sheets of metal at high-~Lt~c~uL~
and pillow-~YrAn~linq the sheets to form a heat ~Yrh~n~e
plate 14 ; seam ~ l ~ i n~ and "weld dotting" ( i . e ., spot-
welded) two sheets of metal forming a high pressure plate
25 14: and a third new and novel approach utilizing the
aluminum roll bonding or stainless steel seam welding
concept may be deployed to achieve the identical,
"pillowed" ~Yr~n~i rn format having deep cavities .
Preparation of the roll bonded plates 14 requires:
30 taking two sheets of precision aluminum; cleaning and
decrea6ing the sheets; printing a pattern for the fluid-
f low tube circuit on one side of one sheet by silk
screening; preheating both sheets; ~ rgically
bonding the two sheets together in a roll mill forming a
35 panel therefrom; Flnnc~l ;n~ the bonded sheets; inflating
the fluid-flow r.h~nn~l ~ to specification height by using
high },Le~,,uLe air which expands the silk screened areas
.
WO95/28ll6 2 1 8~527 L~.IIIJ., _ ~ r ~
--32--
between the sheets; h1Ank;ng the panel; and attaching
cr~nne~t~r tubes to the PYrAn~led roll bonding such as by
flame brazing.
More particularly, the roll bonded panel or plate 14
comprises a first sheet 46 and a second sheet 48 of
aluminum stock of either the same or r9icBim;lAr gauge
(i.e., thickness). The first 6heet 46 is ~L~d~ed by
silk screening the desired circuit on the sheet using a
"no-weld" ink 66 such as a graphite coating, reflecting
a specific fluid path pattern design. The "no-weld" ink
66 is applied to selected portions of a first blank sheet
46 of thermally conductive Al-lmin~lm stock having a first
sheet top surface 68, a first sheet bottom surface 70
~shown in Figure 11~, a first end 72, opposing sides 74,
and a second end 76 . The f irst sheet 46 generally has a
thickness of about 60/1, 000 to about 65/1, 000 of an inch
and are ~ d during the roll bonding process to
have a finished product having a wall thickness in the
range of about 0 . 020 to about 0 . 030 of an inch thick .
The no-weld graphite ink 66 is applied to the no-
weld areas 78 of the first sheet top surface 68 of the
first thermally conductive sheet 46 to for_ a parameter
inked weld-line drawn around the edge of the no-weld area
78 of the first sheet 46 leaving a small connector
opening 82 at each corner. Application of the no-weld
graphite ink 66 to selected interior portions of the
first sheet 46 forms a pair of non-inked interior weld
lines 84 drawn spaced apart equal distance from one
another to create a serpentine shaped heat transfer
liquid circuit pattern 86 outlined on the top sur~ace 68
of the first sheet 46.
A second thermally c~n~1u~tive ni~n blank sheet
48 (not shown) o~ the same size and thirlrn~cc as the
first sheet 46, having a second sheet top surface 68, a
second sheet bottom surface 70, a first end 72, opposing
sides 74, a second end 76, and a thickness of about
60/l,oO0 to about 65/l,oO0 of an inch is aligned with the
~ 2 1 85`527
--33--
fir~ ct 46 and the second sheet bottom surface 70 is
plac~ contact with the inked top surface 68 of first
sheet~-45. The inked no-weld surface areas 78 of inked
sheet 46 placed together with the un-inked sheet 48 forms
a double sheet panel 88 as shown in Figure 12 having a
serpentine shaped circuit pattern 86. The non-inked
lines 84 are welded together; however, the no-weld
graphite ink 66 separates the top surface 68 of sheet 46
from the bottom surface 70 of sheet 48 in the no-weld
areas. Almost any continuous pattern could be inked
providing chilnn~lc or cavities for a particular
appl ication .
The panel 88 is heated to approximately 315.6 C,
(600 F), and moved through a rolling mill under high
pressure, typically one to ten tons pressure per s~uare
inch gauge, such as described in U.S. Patent 2,690,002 by
Grenell, hereby incorporated by reference. The high
pressure roll bonding process reduces the thickness of
the panel 88 by approximately 609~ so that each sheet 46
and 48 is about 0 . 020 and 0 . 080 of an inch thick and
preferably about 0 . 025 of an inch thick. The roll
bonding process hermetically bonds the non-ink-coated
weld line surface areas 84 of the panel 88 together
forming a welded double sheet roll bonded panel 89 having
interior weld joints 90, end perimeter weld joints 92,
and side perimeter weld joints 94.
~-roll bonded panel 89 is then placed between a
pair~Elatens and connected to a pressurized gas supply
means via the connector opening 82. Upon completion of
this high-impact bonding process, the solidly bonded,
double-thick plate 14 is pierced, at an appropriately
designated position, directly into the non-bonded
graphite pattern, and the pillow pattern is then expanded
(inflated between platens) with a high pressure gas such
as nitrogen or air to a predetc~rmi n ~d amount forming
conduits 98 conduits lO0 between the welds 90-94 forming
a roll bonded heat transfer circuit or plate 14 and
~M~NDED SHEE~t
2 ~
-34-
crea ~ a precisely engineered path of heat transfer
fluid~ vel across the entire heat exchange plate 14
which also serves to support the food articles thereon.
Roll bonding aluminum sheets 46, 48 provides
substantially flat top and bottom surfaces on the first
and second sheets 46, 48. The liquid heating fluid
channels 50 are designed to allow maximum liquid heat
transfer evenly distributed through the entire surface of
the plate, achieving by their liquid transfer channels 50
the maximum uniform heat transfer on the entire plate 14
surface within the narrow range of +0.5 C, (+1 F).
Figures 13 and 14 show a cross-sectional view of an
embodiment of a roll bonded plate 14. As shown in the
enlarged cross sectional views of Figure 14, the top
sheet 46 can be formed having a smooth surface or having
creases 96 therein at the point of the welds 90-94 for
draining excess juices into the fat retention container
60. Figure 15 shows a roll bonded panel having a
plurality of conduits and dimples formed therein to
control the flow of the fluid therethrough.
A continuous process for roll bonding aluminum is
set forth in Alcan Aluminum's, Algood Aluminum Subsidiary
Engineering Information Bulletin, Algoods Roll-Bond
engineering Guideline Bulletin, and Society of Automotive
Engineers, Inc., ("SAE")'s Bulletin No. 830023 the
disclosures of which are incorporated herein by
~ =
refe ~ .
~ ler's Temp Plate~ Bulletin, the disclosure of
which is incorporated herein by reference, is fabricated
by resistance seam-welding, resistance spot-welding, and
arc welding techniques by taking two thin metal sheets
composed of 304 stainless steel, 316 stainless steel,
nickel, MONEL~ nickel-copper alloy, inconel alloy 600,
inconel alloy 625, carpenter stainless steel, carbon
steel, Hastelloy~ alloy B-2, and other metals and alloys
thereof, and by welding a seam around the outer edges and
in a selected pattern between the two sheets bonding the
EN~) S~
WO95/28116
--35--
sheets at the weld junction.
Resistance spot welding requires pressing two sheets
of netal together, preferably steel, and more preferably
stainless steel. Two elevLLvdes are used to apply a
5 current through the two sheets of netal. Due to the
resistance to electrical f low at the metal contact
surfaces, the area thero;nl L heats up and forms a
small molten puddle. As the y~ uL~: is retained and the
current shut off, the molten puddle freezes forming the
10 ~3 ~` ~ between the two meal sheets such as shown in
Figures 16-21. Figure 16 shows a typical guilted pattern
having resistance spot and sean welding, and Figure 17
shows a guilted serpentine pattern having resistance spot
and seam welding.
Resistance seam welding is produced by a series of
overlapping spot-welds. Current passes through the metal
as a wheel shaped electrode rolled over the sheets held
together by ~L_SI~ULe. The width and length of the spot
welds can be controlled by the width of the electrode and
the current on-of f time .
Multiple spot welds may be formed between the two
sheets at the desired points to increase the DLL~ LII of
the plate 14 formed thereby, and increase heat transfer
between the sheets and the liguid circulating
therethlvu~ll in a free flow pattern as shown in Figure
18 . The spe~ l y rlo~ignod heat transfer plate 14
configuration may utilize sheets 46, 48 which are spot-
welded and high ~L~S~ULe: oYr~n~lod with one side flat with
the second side slightly pillowed or dimpled which is the
preferred method for utilizing stainless steel sheets.
As shown in Figures 19 and 20, the dimple one sided plate
14 is constructed by machine plln-hir~ and swaging the
sheets prior to welding to increase the flow area in the
r l~8~o': thereinbt:i ^-,.
The resistant welding techniques may also be
employed to produce a single: ed surface plate 14,
wherein the plate 14 is comprised of two sheets of
2 1 855~7
Wo95128116 r~ 166
--36--
material of different thirl~n~cc~ and one side is
inflated as shown in Figures 21 and 22 providing a flat
surfaae on one side of the plate 14.
The resistant welding ~erhniq~ c may also be
5 employed to produce a double ~ surf ace plate 14,
wherein the plate 14 is comprised of two sheets of
material of different thi rl~n~c,c~c and both sides are
inflated as shown in Figures 23 and 24.
The above described manufacturing techniques are
10 further ~nhAnred by the option of subjecting the impact-
bonded, or roll-bonded aluminum plate 14 to deep-drawing
operations . In the deep drawing ~LOC~dUL ~, the entire
roll-bonded tray 14 is pulled by vacuum into a nold (not
shown) forming a de~ L~....I or deep-well tray 108
according to the desired shape of the mold as shown in
Figure 25 formed from a re5istant welded plate having
both a deep-drawn first sheet top surface 109 and deep-
drawn second sheet bottom surface 111.
Depressions 104 forned within the de.:~ dL~. .I tray
108 of the present invention may be designed to form
shallow vessel6 106 having raised walls ranging from
about ~ inch to about 14 inches deep in one or both
sheets 109, 111, and still maintain the thin high heat
transfer advantages of the flat roll bonded plate 14 as
illustrated in Figures 26 and 27. The vessel(s) 106
yL o-lu~:ed may be f ormed having a shape that is round,
elliptical, ~ JulArl or any desired food shape
conf iguration .
For example, as shown in Figure 26, oblong shaped
vessels 106 may have depressions 104 which extend
downwardly from the deep-drawn first top sheet 109 and
upwardly from the dee~ 1L I second bottom sheet 111
wherein the vessels 106 are aLLa~ d in a staggered
formation between the deep-drawn trays 108. As shown in
Figure 27, the cook and staging grill 10 may have a
combination of formed deep-drawn trays 108 containing
vessels 106 formed between flat plates 14 and deep-drawn
.
2 1 85527
.
plat~8, or vessels 106 formed extending downwardly
from~r-drawn first top sheet 109 toward a flat first
bottom-sheet 70, wherein the thickness of the frame 15,
17 provides a spacing and sealing means between f lat
5 plates 14 and the formed deep-drawn trays 108. The deep-
drawn plates 108 may also having additional heat transfer
capacity due to having a greater surface area in contact
with the heated food article 13. The deep-drawn trays
108 may be designed to heat the vessel 106 and food
products 13 contained directly in the vessel 106, or to
neat f ood contained in a prepackaged container, such as
a frozen "TV" dinner or soup, held within the vessel 106
to a cooked equilibration temperature of up to 96.1 C,
(205 F), +0.5 C, (+1 F), from a frozen state,
refrigerated state, or ambient state. The process is
applicable to precooked, or fresh to-be-cooked food
articles 13.
Figure 26 is perspective view of cook and staging
grill of Figure 7, showing plates formed having
depressions or vessels 106 for containing food articles
13 therein formed between the deep-drawn plates 108. As
illustrated in Figure 26, the formed heat exchange deep-
drawn plates 108 can be designed to receive round or
elliptical food articles 13 (such as hot dogs,
knockwurst, sausage and brats), whereby two contiguous
plates 108, each conforming to a half-diameter of a food
produ~t~3, oppose each other in such manner that the
half~;eter profile .configurations will surround the
l~,u-l~alliptical food article 13, thereby enabling the
food article 13 to be placed between the two plates 108
for high-speed ~h~rr-l; zation and staging procedures into
the conductive e~uivalent of a round ( or elliptical )
configuration. This unique and novel heat exchange
design, under which food articles 13 are thermalized via
recirculating heat exchange fluids in pillow-expanded,
fluid-traveling channels within the formed plates 100,
provides far greater ~ood safety during thermalization
and staging processes, than the currently utilized,
AMENDEG SH~E~
~ W0 95/28116 , ~2 1 8 ~;~z 7
--38--
heated "rolling pin" or hot water device6 now in practice
f or this purpose in the industry .
The cook and staging grill 10 is designed to retain
food articles 13 in a clamped state or a nested state,
5 via either horizontal or vertical fastening r ~ n; ~ ,
such as the hinges 54, for the time period required to
assure sllff;c;~ t internal product t~ ,- Clt
equilibration (i.e., the time period required to meet the
time-t aLUL-~ paU.og~-. lethality curves det~rm;n~l by
10 the USDA and FDA to provide effective pathogenic risk
u~na, L) . Under the federal ~;r]~l in~C: for thermal
kill of food-borne ~c.tl~o~-:ns, wherein food articles are
rendered safe for ~ Lion by ~U~O~UL~ to required
LuL~5s for minimum time spans, the opportunity to
15 stage (i.e., hold) the food articles 13 for extended time
periods and to serve same as dictated by ~;UD~ demand
is ~ h~'i efficiently with the cook and staging
grill 10 of the present invention.
The control process f or the cook and staging grill
20 lo is a ~ hF~Cl by Gonnecting the ~h~ l ly conductive
grill plates 14, 108 to an electronic monitoring means
110. IloL~aov_L, in the preferred 'i- L, the control
means comprises a computerized control system and alarm
system 24 controlling the process and recording the time
25 and t~ clLuL.: variables for the multi-deck cook and
staging grill 10. Each cook and staging grill plate 14,
108 has one or more ~ les 42 inserted into one or
more of the food articles 13 for measuring internal
product t~ c-LuLc:, in order to achieve the most
30 critical functions of control over specific, pathogen
lethality time-t~ ~-LUL~ o~,uLe,s and sllh~equ~nt cook
and staging periods . Each th- ,co-lr- e 42 is connected
(i.e., i ` ' '-- or attacned) to a selected protrusion 62
on the underside of the grill plate 14, 108 ~or
35 pe~ LL~ ting the food article placed in that position,
permitting measù~ L and on-site read-out of its
internal c.LuL~:. Furthermore, the th- - le 42
--3 9--
is =~le of ;delivering constant internal product
temp~re-monitoring information through an eleetrieal
connee~on means such as an electrieal eable ( not shown )
from its position on the lower grill 10 surface's
5 protruding member 62 to a microproeessor unit or eomputer
114 .
The eomputer 114 eontrols the proeess and receives
output data from the pump 20, heater 18, and timer 116.
The computer 114 records the time, temperature, and batch
10 data from at least one limit switch 118 (not shown)
ele~ LL~. ocl~nically linked to at least one safety lock,
preferably a magnetic loek 58 for eaeh individual plate
or tray 14, 108. The computer 114 in the preferred
F~mho~lir~nt is adapted to process input from up to ten
15 thermocouples 42 in eontaet with the food artieles 13 for ~:
preeise monitoring or the internal produet temperature
throughout the cook and staging proeess continuously or
at speeified time intervals. The temperature in measured
mieroseeonds and displayed on the instrument eontrol
20 panel 38 with LED or other light displays, sueh as shown
in Figure 2, eontaining red (in proeess) indieator lights
122, green (ready to serve) indieator lights 124, time
indieators 126 for eaeh individual tray, and at least one
temperature indieator 128 which can indicate the
25 temperature of any individual thermocouple 42 or for each
tray 14, 108. It is eontemplated that eaeh tray 14, 108
- may ~an individual temperature indieator 128. Upon
clos~the .tray 14 containing food artieles 13, the
magnetie lock beeomes engaged and the red light indieator
30 122 eomes on. During the neating eyele the red indieator
light 122 remains on and the rising temperature of the
tray 14 is observed through the temperature indicator
128. When the food articles 13 have reached the desired
preset temperature f or the desired preset time the
35 temperature indieator will indicate the equilibration
temperature has been reaehed, the green indieator light
124 will turn on,
AMENDED S~Et
2i 85527
--40--
the ~ indicator light 122 will turn off, and the
magn~ lock 58 is released or rendered releasable
permitt~ng the tray 14 to be opened and raised providing
access to the rood articles 13 for serving. The computer
114 records the time and temperature data providing proof
that the food articles 13 were processed in the cook and
staging grill 10 for at least the minimum time and
temperature necessary to achieve thermal lethality for
the Escherichia coli 0157:H7 bacteria or for the desired
time and temperature parameters needed to achieve thermal
lethality of any other pathogen and provide a safe food
product 13 for the consumer.
Using the cl~lnch~l~ cook and staging grill 10 of the
present invention involves a simple ~L.,ce.lu~: due to the
automation and control of the device. For example, the
cook and staging grill 10 is preheated to about 160 F.
Frozen 1/4 pound meat patties, such a6 a ha~burger
patties, beef, pork, chicken meat, egg or vegetable
patties encased in air evacuated plastic pouches 127 or
other containers as shown in Figure 28, at about 0 F to
about 40-F. are placed on the upper heating surface of a
first tray 14 and a second upper tray 14 hingably
connected thereto is closed holding the meat patties
thereinbetween. Closing the tray 14 activates the
fll-~ ~ ou~les 42 and temperature indicators 128, red in
process light 122, ti~er 116, magnetic lock 58, and
c~ ed controller and alarm system 24. The
preh,e~ trays 14 heat the meat patties to about
160 i:~ in about ten to about 17 minutes. The time and
temperature is recorded by the microprocessor 24 and
shown visually on the indicators 128. The computer 24
monitors the process and records the temperature of the
h~ r patties on each tray 14. Upon reaching the
preselected temperature of 160DF. a green indicator light
124 flashes and an audible alarm sounds indicating the
hamburger patties are rully cooked, pathogenically safe,
and ready for serving. q'he lock 58 is disengaged and the
tray 14 is lifted manually or automatically by a
AMEN~E~ si iE~r
-41-
me~h~l device.
~ llustrated in Figure 29, a temperature and time
graph shows typical curves produced usinq the cooking and
staging grill 10 wherein frozen 1/4 pound meat patties or
5 chilled fresh raw meat patties at about -17 . 8 C to
l.l C, (O'F to 30 F), are heated to about 71.1~C,
( 160 F), in about ten to seventeen minutes ; pre-grilled
patties are heated from about 43.3 C, (110 F), to about
71.1 C, (160 F), in about eight minutes: and staged 1/4
pound meat patties are heated from about 62.8'C, (145~F),
to about 71.1 C, (160 F), in about five minutes. The
cook and staging grill 10 is capable of maintaining the
selected temperature and product therein in first quality
condition in pouch 127 form from about four to about six
15 hours.
Moreover, the computer 114 is connected to a
computerized temperature monitoring data transmitter 130.
The data transmitter 130 transmits accurate, up-to-the-
minute t~lpel~.LuL~-monitoring information, from any
20 individual restaurant, to a central data recipient,
thereby enabling regulation and monitoring of compliance
and comparative efficiency, at separate retail outlets,
by the central data recording entity.
The foregoing detailed description is given5 primarily for clearness o~ understanding and no
nnPrP~ ry limitations are to be understood therefrom,
~- for ~ication will become obvious to those skilled in
the ~on reading this disclosure and may be made upon
departing from the spirit of the invention and scope of
30 the ~rp~-n~9~d claims.
AM~NDED S~!EE~
