Note: Descriptions are shown in the official language in which they were submitted.
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This invention relates to cooking pans especially
adapted to prevent food cooked therein from sticking and to
improve its texture.
In the case of conventional frying pans, although
there are many different types and designs, including loop type r
pans, many of them cause sticking when food is cooked in them
unless a large amount of cooking oil is used. Furthermore, when
frying eggs for example, in such frying pans, there is no provi-
sion for expelling gases other than from the surface, so that
10bubbling occurs and the foQd is not well cooked.
As a means of avoiding these difficulties and poor
performance the inside surfaces of pans have been coated with
polytetrafluorethylene (PTFE); however the known PTFE coatings
are expensive and are not durable and suitable for extended high
intensity use.
The present invention provides a cooking utensil
having at least one pan of porous material comprising a base
portion having a porous cooking surface and a pe~ipheral wall
portion connected to or integral with the base portion, the base
20portion having cavities substantially throughout it which are
adapted to be filled with oil to produce a film of oil on the
cooking surface to prevent food which is being cooked sticking
thereto. Preferably the peripheral wall portion of the or each
pan is provided with at least one aperture or groove through
which may escape gas from material which is being or has just
been cooked in the pan.
In an other aspect, the cooking pan may be provided
with a piurality of rows of apertures in the peripheral wall
portion of the or each pan.
In an alternative embodiment of the present invention,
the cooking utensil may comprise two pans which are hinged to
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each other so that they may be moved between an open position,
in which they constitute separate pans, and a close~ position
in which they collectively constitute a close~ box. In this
instance, each of the pans may be provided with a handle.
In an other aspect of the present invention, the
cooking pan may be combined with a weight for placing on cooked
material in the pan to expel gas therefrom. Preferably the
weight may be apertured to pexmit the escape of gas therethrough.
Specific embodiments of the invention will now be
i 10 described with reference to the accompanying drawings, in which:
G ~ Fig. 1 is a plan view of a cooking pan according to
the invention;
Fig. 2 is an enlarged cross-sectional view of the base
; of the cooking pan of Figl l;
Fig. 3 is a cross-sectional view of the base and side
wall of a cooking pan according to a second embodiment of the
invention;
Fig. 4 is a perspective view of a weight member
according to the second embodiment;
i ~s - la -
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Figs. 5 and 7 are cross-sectional views of the base and side wall
of a cooking pan according to the second embodiment, showing alternative r
forms of vent;
Fig. 6 is a cross-sectional view of the cooking pan according to
the second embodiment in use showing four layers of cooked food with the
weight member of Fig. 4 in place; and,
Fig. 8 shows, in side elevation a cooking machine in which the
cooking pans of the present invention may be used.
Referring now to the drawings, and to a first embodiment of the
invention, numaral 1 denotes a cooking pan comprising two pan elements 2
and 3. These pan elements are hinged about a spindle 22 by means of lugs 20
and 21 formed on the pan elements. Each pan element 2 and 3 has a handle
18 and 19 respectively, by which the pan elements may be opened and closed
in the directions of arrow A.
The cooking pan of the invention may be made from any of aluminum,
copper, stainless steel, iron, composites of these metals, or ceramics, or
other suitable material, but according to the invention it has, as shown
particularly in F~g. 2, a large number of small cavitles and pinholes 4
formed in the interior and on the surface of the material from which the
cooking pan is made. In use an oil membrane 5 is formed on the surface of
the pan elements and this membrane is connected to the cavities and pinholes
which are filled with oil in use. The eavities and plnholes are filled
with oil, and the membrane formed, by either heatlng or vacuum means, or both,
in the presence of the oil.
Preferably the material of which the cooking pan is made is of
a coarse-grained construction, as being particularly suitable for having
cavities and pinholes formed therein and therefore for oil filllng. It
is reasoned, although this is not limiting, that such materlal and the
presence of the oil membrar.e in use, is conducive to a low thermal conductiv-
3~ ity of the material with which the food comes lnto contact and therefore
that sticking of the food is minimized.
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It is to be understood that ~he inventlon is not llmlted to double
pans of the type described, and single pans, or pans of any shape may be
used. However better results are obtained where the pan is flat. The
invention is also not limited to any particular material of construction
of the pans.
A second embodiment of a cooking pan according to the invention
will now be described.
As before, the cooking pan 1 may be composed of pan elements
hinged and with handles, all as shown in Flg. 1. However, and with
parti~ular reference to Fig. 3, in this embodiment the side walls 10 of
each pan element have a number of holes 11 formed thereln in hole groups 12
and 13, hole group 13 being nearer the base of the pan than hole group 12,
and the holes of each group being approximately equidistant from the base
of the pan. Hole group 13 is at such a height as to be just above the
liquid surface for the particular pan in question when liquid egg ifi poured
into the pan for a first cooking. The liquid egg is denoted in Fig. 3 by
numeral 14.
As seen in Fig. 4, a weight member consist6 of a plate 16 having
a number of holes 17. These holes may be, for example, about 6 mm. in
diameter and the plate should be slightly smaller in size than that of
each pan element 2 and 3. Suitably this discrepancy in size will be about
1 cm. all round the perimeter of the weight member.
In Fig. 6, four-layer fried egg is shown, ~he egg being denoted
generally by 15, and weight member 16 is shown in place on top of the
cooked food.
The cooking pans of the invention are particularly suitable for
J~ use in a cooking machine such as is described in our copending Canadian
patent application ~o.~7~ filed m~ rc~ 7? . S~ch a machine
i6 shown in Fig. 8 of the drawings, in which cooking pans 1 are movably
disposed on a rotary table 23 of the machine. Cooking material, for
example, liquid egg, is supplied from tank 26 to the cooking pans by means
of supporting arm 24 and dispenser 25.
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When using the cooking pan of this embodiment for the preparation
of multi-layer cooked food, for example, fried eggs, liquid egg is poured
into both pan elements 2 and 3. This may be done manually or by means of
the machine described in the abo~e-mentioned copending application. When
the egg in the pan elements has ~ust l-ardened, that in pan element 2 i~
transferred to psn element 3 to give a two-layer egg and when this is done
occluded gases are vented to the outside via hole group 13. In the next
step, liquid egg is poured into pan element 2 and when this has just harden-
ed, the two-layer egg in pan element 3 is transferred to pan element 2 to
1~ give a three-layer egg, occluded gases being vented to outside via hole
group 12 as well as residual gases still being vented via hole group 13.
In a third step, liquid egg is poured into psn element 3 and the three-layer
egg in pan element 2 is transferred to pan element 3 to give a four-layer
egg. In each step weight member 16 is placed on top of the egg as it is
cooking so as to assist in expulsion of occluded gas from the food. When
the layers of food are higher in the pans than the hole groups 12 and 13
and weight member 16 is in place occluded gases will be expelled through
holes 17.
As an alternative to having a number of holes formed in the side
walls the cooking pans of the invention may have a number of appro~imately
vertical slits in the side walls thereof. The lower ends of these slits
may be at the level shown in ~ig. 5, that is at approximately the level of
hole group 13, or they may be as shown in Fig. 7, and be substantially at
the base of the cooking pan and therefore under the level of ~he first
layer of cooked food when the pan is in use as has previously been described.
It will be understood that cooking pans of this embodiment of
the invention are not limited to double pans of the type described and single
pans, or pans of any shape, may be used. Additionally the invention i8
not limited in respect of the member and size of the holeæ in the weight
member, or the size of the we~ght member, or in the exact size and disposition
of the holes or slits in the side walls of the pan elements.
