Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
`- ``` 1~75~76
The invention rQlates to procedure and apparatus for
heat proces~ing raw ~ood products and particularly, relatively
flat products such as meat patties in order that they may be
irozen and on reheating may then be dlspensed, ~or example,
to restaurant customers. A phase of the invention deals with a
contlnuous processing treatment of food products with live
steam, utilizing a water bed and within a substantially fully
enclosed oven.
Heretofore, there has been no fully satisfactory
approach to the problem of heat-processing food products, such
as meat patties, which involves blanching or cooking thereof,
whereby the products may then be stored under refrigeration
for direct usage by restaurants or for store distribution and
sale to ulti ate customers. One approach has been the use of
an infrared system. However, this has a main dis~dvantage
of tending to spoil the appearance of the finished product
such as a meat patty, to cause an excessive loss of juices
and for~ation of a crust-like surface on it. One of the main
! difficulties in this procedure and other conventional
procedures is the considerable loss of weight by shrinkage of
the food products within a range of 25 to 30~ which amounts to
about 3.2 oz./lb. 1088 in a meat patty. Another adverse
ieature has been the difficulty of obtaining uniform results
throughout individual patties and as between a processed group
of patties. ~-
There has been a need for an approach to the heat
; processing of food products which will ~inimize shrinkage
and, at the same time, maximize flavor and succulence, avoid
- crusting and particularly, which will assure uniformity of
treatment and appearance, both throughout its body, as well as
from the standpoint of its opposed flat sides. This need has
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1075076
b~en partlcularized by requlrements that have arl-en ln
connection ~ith preseDt day quick-service restaurants.
The noed i8 for an improved, highly ei~lcient blanching or
cooking of raw ~ood product~, such as meat patties, that may
be ~tored under reirigeration in readlness for quick heat-up
~heD a customer places his or her order. The blanching is
subJoct to requiremoDts of the Federal DepartmeDt of
Agriculturo, particularly iro~ the standpoint oi' saDitary
operatioD. ~eat patties, ior e~ample, are required to be
brought up to a processiDg temperature of at least 138- F.
It has thu8 beeD aD obJect oi the iDveDtloD to
provide a ne~ and improvod approach to the proces6iDg of
i'ood products such a~ meat pattio~.
Aootber object has been to devise a process ~hich
~ill enable the utilizatlon of live steam iD a highly ~-
e$iicient and effective manDer to attain a uniform, iull,
hoat treat~ent or processiDg oi food product duriDg it8
~ove~ont through the processiDg chambor of a substantially
enc~osed oven.
A iurther obJect oi' the invention iDvolves the
provi~ioD of a ~ste~ and procedure ~hich ~ill eD-ble a
~ubstaDtially unifor~ and active utilization oi live steam
that is in oifect ~oisture-saturated and ~hich i~ applied
iully about advancing i'ood products in such a ~anDer a~ to
oificientl~ ma~i~ize utilizatioa oi the heat content of the
stea~ and onabl- a coDtiDuous ~OvemeDt of the food product
~ithin the treating cha~ber of an ovon, all ~ithout producing
a h-avy fog oi veDted 3tea~ within tho working spaco or the
room ~ithin ~hich tho food products are being proces8ed.
A still iurther ob~ect oi the iDveDtioD is to
~a~i~ize uDifor~ity of heat tr-at~oDt oi a iood product, and
.
.
l07sa76
at tbe same tlme, to miDlmize chrlDkage and lo~s of ~elght
during the proces~ing and in ~uch a manDer as to provlde the
product ~ith toDderDess, eveD coo~ing treatment, aDd
uniformlty oi color
Those and other ob~ects oi the iDventlon ~ill appear
to tho~e ~killed in the art irom the illu~tratod embodiment and
the clal~s
In the dra~iDgs, FIGURB 1 i8 a ~ide vie~ 1D 01eVatiOD
and p-rtial section sho~lng an apparatu~ system or arrangement
devl~-d ior utllizlDg the prlnclples and process phase oi the
iDveDtloD;
FIGURB 1A 1~ aD enlarged sectional detail of an upper
portion oi the oven oi FIGUR~ 1;
FIGUR~ 2 18 a irag~eDtal top plan sho~iDg details oi
the feed ~echanism and the ~tea~ supply system i'or the oveD of
FIGIn~B 1;
FIGUR~ 3 i~ aD eDd vie~ on the ~cale of aDd takeD
aloDg liD~ III oi' FIGURE 1 ~hich particularly illustrate~
~ean~ ~or restrictiDg end openings in the oven and ad~ustiDg
them to provide Decessary clearaDce for continuous ~o~emeDt
or passage of the food products as carried on a conveyor belt
therethrough;
~Dd, FIGURB 4 i~ a greatly enlarged ~ide sectional
fr-gmeDt illu~trating ~tea~ through ~ater i'lo~
- ID carrying out the invention, food products such as
moat patties F are progressively supplied at ODO eDd of the
upper for~ard roaches of a CODtinUOU~1Y mOViDg belt 20 of open
~e6h-llke CoD~trUCtioD OD ~hich they are carried iDto aDd
aloDg tho proce~iDg chamber or cooking housing of an oven C
fro~ a longitudinal entry end portion A thoreof In a
preli~inary operation, the food products F ~hich, aiter being
stamped-out ~ucce~sively as tran~verse groups or lines, for
1075076
e~ample, oi ~ix patties ~ay be moved iDto aDd through a
for~ardly advancing roll pass deiined by a palr oi scorlDg
roll~ 19. The rolls 19 carry small spaced-apart aDd
staggered pin-like pro~ections to ~core the patties F irom
opposite ~ide6 thoroof before they are delivered to a
continuous convoyor belt 20. The iood products F are tbeD
advanced at a suitable ~peed i'or, for example, approxi~ately
1.76 ft. por iDute (using, ior e~auple, an oven oi 15 ieet
iD length, 21-1/2 iDches in width and a depth oi about 12
inche~ above it~ coDdensate collecting tray 17), aDd applying
live stoam at a temperature in the neighborhood of about
180- to 230- F.
The iood product6 F are advanced longitudiDally
ior~ardly on a horizoDtal plane along and through the chamber
of the oveD C and out irom oppo~to exit end portion B.
~t this tim , thoy have been fully stean blaDchod or cooked.
A~ sho~n particularly in FIGUR~ 1, the products F ~ay theD
be 6uccessively movod OD the belt 20 through an air-dryiDg
~tatioD or chasber G and a nitrogon ireezing cha~ber oi - --
8tatiOD ~, for deposit in a suitable collecting container I.
The frozen product~ F may theD, having attainod a temperature --
oi 0 to -5- F., be packaged aDd stored for shipaent to the
place of sale or u~age.
Live steam ay be supplied by a gonerator 30 at a
suitable ab~olute pressure, e.g. oi about 250 to 325 lbs./
~q. inch a8 ~Ddicated by gauge 42, and then ~oved through a
main ~upply liDe or pipe member 31 at a corro~poDding
temperature oi about 400 to 424.5- F., through oDe or both
control valves 32 J 32' to ~team supply ~pray system or
pipiDg D, through eDtry pipe lino 33. A dasired te~perature
ior supplylDg the steam to the oven C may be attained by
iO7S076
vie~iDg pressure gague 43 in the line 33 and ad~ustlDg the
control valves 32 and 32'. Steam is introduced substantially
uni~or~ly, indlrectly into and along the cha~ber oi' the oven C,
by fir~t moving it diroctly into and then up~ardly through a
heated body oi ~ater being aaintained in the condensate
collecting tray 17 which serves as closing-off botton wall 17
of the oven The level of wator withiD the tray 17 18
maintaiDed substantlally coDstant by a centrally di~posed,
vertically extending, overflow drain pipe 18 which may extend
(as shown in FIGUR~ 1) upwardly through a lowermost, centrally
coDvergiDg, concav~ botto~ portion of the tray 170
The belt 20 is shown at one end positioDed for
rotat~ OD OD an idler drun or ~heel 21, and is positively
driven at its other end by a drum or wheel 22. A suitable
actuating ~ean6, such as an electric motor 28, is positioned
OD supporting fra~e structure 14 to drive a gear reduction
unit 27, aDd through the agency of a pulley 26 ~ounted OD
its shaft to, in turn, drive a belt or chain 25 and a drum
~ctuatiDg pulley 24. It will be Doted that the longitudinally
for~ardly ~oving upper reaches of the belt 20 extend on the
pulleys 24 aDd 26 above the tray 17 aDd its water level,
through the oven C and the stations G and H, and that its
return reaches extend bolow the tray 17 and thus outside the
statioDs H, G and the tray 17 of the oven.
FIGUR~ 2 particularly sho~s the layout of the steam
8upply ~ystem or piping D which i8 located beDeath the
conveyor belt 20, has a horizontal length extent substantially
correspoDdin~ to the length oi' the cha~ber oi' the oven C, and
has a ~idth e~tent substaDtially correspondiDg to the ~idth of
the coDveyor belt 20. As ~ho~n, a pair of stea~ distributioD
pipe ar~s or headers 34 and 34' are coDDected at one end to
`` 1075076
the entry pipe liDe 33 and are closed at their oppo~lte eDds
Transver6e header arm 34 i~ provided with a staggored serie~ oi
sido~i~e or longitudlnally extendlng, tran~versely ~paced--part,
spray ar~ ~o~bers or pipe~ 35 that are of s~aller diameter aDd
are connocted to receive stea~ thereirom It ~ill be noted
each header ar~ ~e~ber 35 i8 8hO~D provided ~ith pairs oi
up~ardly op-n and about t~o inch ~paced-apart spray opeDiDgs
therealoDg A ~econd 6et oi stagg~red spray arns 35' oi the
sa~e coDstructioD a~ the arms 35 are mounted to pro~ect fro~
the ~ecoDd cros~-estendiDg header arm 34' As 8hO~D iD
FIGURE 2, the spray ar~s 35 have a ~taggered relatioD with
respoct to the ar~ 35' Valves 32 and 32' may be employed
to not only control the pres~ure aDd flow to the iDdividual
headQrs 34 aDd 34', but to also co~pletely shut-ofi' ilow
to either, ii de~ired
It i~ oi great importance to the present iDvention
to po~itioD the ~pray steam supply pipe system D belo~ a
~aiDtained level of ~ater iD the botto~ tray 17 An optimu~
spacing i6 about oDe iDch fro~ the top level oi the ~ater iD
the tray 17 A~ sho~n, an upright, overilow type oi drain
or level-~aiDtaining pipe ~e~ber 18 extends substantially
coDtrally fro~ aD area oi Da~i~u~ coDcavity of the pan 17
It ~ay thus be e~ployed to ~aintaiD the body of water at a
suitable stea~ receiving level ~lthin the tray 17
ID utilizing the 8y~te~ sho~n iD FIGURES 1 and 2,
and before the starting of the oporation, the pan 17 is
filled-up ~ith ~ater to an averago depth of about teD iDche-~ -
aDd i8 pre-heated clo6e to a boiling te~perature of about
212 F Thi~ ~ay be done by applying ~tea~ under cookiDg
pres~ure for about t~o ~inute~ b~fore the patties or other
food products F are to be iDtroduced
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`` 1075076
It has been i'ound tbat greatly improved rosult~ aro
attAined by using a steam supply ~ystem or apparatu~
arrangement D ~hich is malntalDed in a submerged or belo~-level
posltloD throughout the operation aDd ~ith respect to ~ater
carriod by and being conden~ed ~ithin the tray 17~ Heretoiore,
the operation ~as coDducted ~ith the ~ystem located above the
level of conden~ate, but coverlng of the ~team veDts ~ith a
level of ~ater such that the stoam issues as such but in a
moisture saturated condition ~as found to provide a solution
to the problen of obtaining a fully uniior~ type oi blanching
or cooking operation ~ith the oven C, and from the staDdpoiDt
of assuring a uniiorm color of, for example, meat patties
The depth oi the spray Dozzle or assombly iB suificient to
substaDtially iully ~aturate the ~toam and move it out of
the ~ater in tho form oi an active cloud This approach is
particularly importaDt $rom the staDdpoint of a continuous
type oi operation in ~hich food patties F are succe~sively
advaaced through the oven, and are to be effectively as~ured
of a uDifor- appearance and tastoappeal Other important
advantages are attained by such sub~erged application or
indirect steam introduction, including an increase in
condeDsate collected in the tray 17, and a marked minimiZatiOD
of the a~ount oi steam ~hich i8 vented from opposite open end
portions A and B of the oven C Thu~, it is DO~ practical to
elimiDate a ~team pick-up system such as ~ ~ithout producing
a dense ~team fog ~ithin the roo~ in which the oven C is
located
Steam may be economically provided at a relatively
high pressure ~aDd thu~ temperature) by generator 30, as
previously indicated The pressure may then be reduced-do~n
1075~76
or throttled by ad~usting the control valves 32, 32' to
provido a suitabl~ entry temperature iD the Deighborhood
of 180 to 230 F and a correspoDdiDg absolute pressure.
The steam, however, should be maintaiDed at a sufflcient
temperature to assure that the food products, e.g. if they
are meat patties, attain a mini~um iDternal cooking temperature
of about 138 F and up to about 170 F, ~ith an opti~um
temperature range oi steam of about 210 to 220 F.
U~ing the ~ubmorged ~team supply system of the
present inventioD, substantlally supersaturated steam is
applied to the food products F through the mesh of the screen
conveyor 20 and in a surrounding relation with respectto
all sides oi the products. If desired, an outside collecting
system E for the steam may be provided which includes
collecting Dozzles or narrow hoods 36 and 37 which are, as
shown in FIGURE 1, positioned with their open ends immediately
above and adjacent to the entry and exit end portions A and B
to exert a pick-up, but not a forceful drawing-out oi the
steam issuing from such end pcrtions. It will be noted that --
the pick-up nozzles or hood6 36 and 37 may be provided with a
slight vacuum or suction pressure by a pump or fan 40 to
assure a complete pick-up of the used i~suing steam. It ~ill
be noted that issuiog ~team pa~ses into an overhead manifold
or header 38, theD through a return flow pipe 39 towards the
steam gensrator 30. In thi~ manner, the steam and it~
coDdensate may be reused by fully opeDiDg a three-way control
valve 41 into a direct return, branch pipe member 39a. The
valve 41 eDables flow to be partially or fully closed-off
~ith respect to tho braDch member 39a and to be partially
or fully closed-off ~lth respect to a branch drain member
39b. Also, the overflo~ pipe from the tray 17 may be
iO7S~76
conDected (not sho~D) to return lts condensate dlrectly to
the drain or to the steam generator 30, as de~ired.
The steam is, iD effect, conceDtrated iD the
processiDg chamber oi the oven C by r-ason of the opposite,
restricted end opeDings A and B. The prOCeS~iDg~ depeDdiDg OD
the type of iood product F, may be efiected at aDy ~uitable
steam temperature snd pressure. A meat patty, ~uch as supplied
to quick service re~taurant chain~, ha~ a mini~um 1088 oi
~eight due to shriDkage usiDg the process oi tho inveDtioD.
This i8 iound to be particularly true by rea~on oi the iull u~e
o~ steam iDdependently of other means, such as infrared lamps
and, importaDtly, is also due to the fact that the stea~ i
only introduced to the food product after having pas6ed through
a depth oi ~ater iD the tray 17. UsiDg the above e~e~plary
~team temperatures as applied to a ~eat patty, a one iDch
~ater levol over the oriiice~ of the stea~ supply system D
represeDts an optimum depth. ~lthough normal shrinkage or
1088 of ~eight oi a meat patty has heretoiore been about 18
to 25% utilizing conventioDal heat processing procedure, 1088
has been reduced to about 5% or less by solely using steam in
the blanchiDg cha~ber, and to substantially a zero 1088 ~ by
utilizing steam after it has pas6ed through a surface depth
oi a body oi heated ~aterO Ucing the e~emplary oven ~ize for
blanching oi meat patties, they may be fully cooked, USiDg a
rate oi ~ovement of the belt 20 such as to retain them withiD
the cha~ber of the oven C irom about one and one-half to two
minutes. The leDgth of the oven chamber or tuDnel may be
adJusted to meet particular requirement6.
The use of pressurized ~team assures that a positive,
above atmospheric pressure is maintained within the processiDg
chamber oi the oven C. Used, uncondeDsed steam i~ues under
positive pressure through the food entry and exit portions A
` 1075~76
and B at opposlte ends oi the oven C. To maxlmize retentloD oi
the llve steam wlthlD the chamber oi the oven C to abstract the
maxlmum of BIU's thereirom, the open ends A and B are preierably
restrlcted to a ~idth that corresponds to the width oi the
belt 20 and to a depth represented by the thickne6s oi the
belt plus the thickne6s oi the iood products F that are
being carrled thereon. To ad~ust ior diiierent thlckness oi
food products, each end oi the main body of top part 10 oi
the oven C i6 provided ~ith an ad~ustable, cros~-extending end
plate 15, see particularly FIGURE 3. Each plate 15 has a pair
oi vertical slote 15a iD a spaced relatioD therealong and is
ad~ustably secured in position through the agency of
thumbscre- bolts 16 which are threaded into or secured to
extend from the oDds of the oven body 10 and are adapted to
be tightened-down on the slotted portioDs 15a. By way oi
example, each end plate may have a vertical ad~ustment oi
about 1/4 to 1 inch.
Since maximum effective use of the steam i8 to be
eifected within the chamber of the oven C, it is important
to provide ior collection oi the coDdeDsate and its re~oval as
iormed. As shown in FIGUR~ 1, the bottom wall oi the oven
repre~ented by the tray 17 ay be somewhat centrally sloped
irom its oppo~ite end~ to converge iDto a traDsverse,
collector trough-like portion through which the iluid level
~aintalning, upright, overilo~ drain pipe 18 is entered~ The
pipe 18, in accordance with the inventioD, exteDds upwardly
- from the iDside oi the tray 17 to a positlon at which it~
open upper open end serves as an overflow drain. Thi~ enables
the carrying out oi the important ieature of the invention in
~hich the steam spray system D is iully submerged below the
water level~
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Since, as previously poiDted out, the steam must
flo~ through a ~lDimum depth oi the body of heated ~ater
(optimum miDimum oi one i w h) beiore it enters the ~paciDg
of the chamber of the oven C, this, iD eiiect, produce~ a
suporsaturation oi tho steam, and a much improved type oi
cooking action on the iood products F and particularly, irom
the standpolnt oi iood product6 that are to be moved iD
succession coDtiDuously through an oven. The steam is
omployed to quickly heat the iood products, ior example,
irom a reirigerated temperature oi about 2~ to 32- F up to
a miDimUm processiDg temperature oi 138, and to maiDtain
them at the raised tempersture to eifect a iull blaDching
or cookiDg of them beiore they leave the oven C.
As sho~n iD FIGU~ES 1 and 3, the maiD or upper body
10 oi the oven C has a centrally opeD upper portion ~or
cloaDing aDd general DaintenaDce purposes. A lid or rooi 11
normally closes-oii this open top portion and i8 8ho D
provided ~ith a pair oi haDdles 12 to iacilitate removiDg
aDd iD~erti~g it iD positlon. TSe opeD top portion o~ the
oveD body 10 has an iDner ilaDge provided ~ith upper leg,
shelf aDd lo~er leg portion6 extending thereabout that
provide a sealiDg iit ~ith similar, co~plementary portioDs oi
an outer ilange about the lid 11. The lid 11 may be secured
in its ~ountod positioD by DUt aDd bolt asse~blies or throaded
; bolts 13 to retain it 1D a good sealed positioniDg under
above atnospheric pressures. For normal pressures iD the
chamber, slde cla~ps may be used to iacilitate lid removal
for ~aiDteDance aDd cleaDiDg-out of th~ oveD. AB shovD iD
FIGUR~ 1, the interfitting co~plementary flange constructioD
oi the parts 10 and 11 is such to insure that coDdeDsate will
flo~ in~ardly aDd Dot outwardly along the upper sides oi its
walls .
1075076
Th~ con~truction of the apparatus 1~ ~uch that a
ra~ iood product that i~ beiag proce~sed, preferablg of
patty-like shape, ~ill be surrounded by upwardly ilo~ing
streams of steam and ~111 be sub~ected to steam, both floving
up~ardly against its bottom surface through the open mesh of
the conveyor belt 20, a~ well as from steam circulating
~ithin the upper chamber of the oven C. The steam is COD-
centratod iD the proce~æing chamber by reason oi the relative
restricted entry and e~it portions A and B. The processiDg
may bo accomplished by aDy suitable temperature. Ho~ever, the
dry steau as ~etted in its introduction to the chamber, should
have a temporature and corresponding absolute pressure to
effect the requisite heatiDg-up of the food product to a
blanchiDg or cooking temperature and requ~site mainteDance of
~uch temperature for the completion of the cooking or blanchiDg
operation, all ~hile the product is being moved on the belt 20
through the oven chamber. As previously intimated, in
addition to steam temperature or pressure, the length and
other di~eD~ions of the chamber or tunnel of the oven C may be
adjusted to meet particular requirements.
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