Note: Descriptions are shown in the official language in which they were submitted.
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Background of the Invention
The present invention relates to a chopped egg
product and a process for producing the same.
Various types of egg products have been produced
for consumer use. Raw egg products have been prepared and
frozen in order that they may be subsequently thawed and
used in the same manner as fresh eggs. More recently,
cooked egg products have been produced which are suitable
for freezing with subsequent thawing and use. These cooked
L~ -egg products are very desirable b~cause of the con-venience
. ,.
of simply thawing the product to permit use by the consumer.
These products and processes for their production are
generally described in the following U.S. Patents.
U.S. Patent 3,510,315 describes a cooked egg
product in which the yolks are separately cooked in a mold
and placed in a larger mold in which the uncooked egg whites
are placed and cooked surrounding the yolk. The mixture is
frozen and a starch material is included in the whites
to provide good freeze-thaw stability. A frozen product
with an egg yolk core surrounded by cooked egg white is
obtained which can easily be thawed and used by the consumer.
Impro~ements on the above process for the production
of cooked frozen egg products are described in U.S. Patent
3,598,612 in which treatment of the yolk with an oxidizing
agent prevents discoloration of the interface area between
the yolk and white. U.S. Patent 3,598,613 describes a process
in which the yolks are heated to a semi-solid state, ground
and then heated to form a solid yolk product. U.S. Patents
3,798,336 and 3,711,304 describe processes and apparatus for
centering of the yolk body in the egg whites before or during
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cooking to form a core of egg yolk concentrically surrounded
by the cooked whites. These products can be conveniently
thawed and sliced and easily used by the consumer without
the cooking and peeling of shell eggs. - -
The above types of cooked, frozen egg productshave been extensively used by restaurants because of the
ease of preparation. A recent addition to restaurants and
institutions engaged in mass feeding in this country,
has been the salad bar in which the customer can prepare
.0 -his own salad with ingredients of his own choosing. A
popular ingredient at these salad bars is chopped or diced
eggs which can be sprinkled on the salad by the customer.
Obviously, the cooking and chopping of eggs requires an
extensive amount of preparation, in addition to the fact
that chopping usually smears the yolk over the egg white
particles resulting in a pasty mess the consumer does not
readily associate with chopped eggs. In addition, when
whole eggs are cooked, they also suffer from problems with
green discoloration of the yolk surface which is visible in
a chopped egg product since the particles are exposed by
virtue of being chopped or diced.
While the cooked, frozen egg products described
above avoid many of the discoloration problems associated
with whole eggs, nevertheless, these products also present
a poor appearance if they were simply thawed and chopped
or diced since the yolk readily smears onto the whites.
A need, therefore, exists for a chopped, frozen egg product
without significant smearing of the yolks on the whites,
which has a smooth texture, and may be readily thawed and
used by the cons~mer as an ingredient in or as a condiment
for foods.
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It is, therefore, an object of the present invention
to provide a cooked and frozen chopped egg product which
avoids significant smearing of the yolk on the chopped egg
white particles. - -
It is also an object to provide a cooked andfrozen chopped egg product in which the yolk is a bright
yellow with an absence of discoloration.
It is also an object to provide a cooked and
frozen chopped egg product which has good freeze thaw
1~ -stability without significant deterioriation of the yolk
and white during storage.
It is also an object to provide a cooked and
frozen chopped eg~ product which has a smooth but firm
texture without significant sticking or clumping of the
particles of yolks and whites.
It is a further object to pro~ide a unique process
for the production of a cooked and frozen chopped egg product
which meets the above objectives which is reliable and
convenient to practice.
SummarY of the Invention
These and other objects are achieved in the present
invention which provides a unique process for the production
of a cooked and frozen chopped egg product.
The present process comprises separate heating of
egg yolks and whites to an internal temperature of between
about 165 - 210F. for a period of time sufficient to coagulate
or effectively cook the yolks and the whites. The separately
cooked yolks and whites are then frozen. A chopped egg
mixture is formed by simultaneously or sequentially chopping
the frozen whites at a critical temperature range of between
about 22 - 30F. to provide a chopped egg mixture in which
minimal smearing of the yolk on the whites occurs during
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chopping and the mixture has a smooth but firm texture. The
chopped mixture can then be refrozen and sold in this
fashion for use by restaurants or institutions as a food
condiment. The prcduct represents a distinct improvement
over cooked chopped whole eggs in appearance and texture
as well as convenience to the user of the product.
A significant factor in the above process which
provides the chopped egg product with such desirable
appearance and texture is the temperature range at which the
10. simultaneous or sequential chopping of the cooked yolk and
white`is carried out. For example, if the temperature of the
cooked egg during chopping is above this temperature range,
extensive smearing of the yolk and the white occurs resulting
in a product with an undesirable appearance. By contrast,
at a temperature below this range, the yolk and the white
tend to shatter or splinter resulting in an excessive amount
of fines whi~h will also detract from the appearance of the
mixture.
The separate cooking of the yolks and whites
together with chopping at the above temperature results in
a frozen diced or chopped egg product that has a desirable
color, texture and appearance that can be thawed and used
by the consumer.
~escription of the Preferred Embodiment
In accordance with the present invention, pasteurized
liquid egg yolks and whites are obtained and placed into
separate containers for heating. It is not critical to the
presen~ inven~ion that the yolks or whites include additional
ingredients although various flavorings, spices, and or
seasonings can be included if desired. It is extremely
desirable, however, to include a water binding material in
the egg whites since the product will be frozen and the addition
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of the water binding material prevents syneresis during
subsequent freezing and thawing of the product. The water
binding materials which may be employed in the present invention
include polysaccharides or carbohydrates such as Golloids,
starches, cereals or flours capable of absorbing and binding
water. Examples of suitable materials include corn, tapioca,
rice and potato starches, flours and the like. Polysaccharides
such as algins, carrageenans, xanthan gum or various other
colloids are also suitable as water binding materials.
Carbohydrates which are particularly preferred are.food
. .
starches which have good freeze-thaw stability or possess
the ability to retain water in the egg white portion after
the product has been frozen and subsequently thawed. The
water binding materials should be present in the egg white
portion in an amount effective to prevent syneresis upon
freezing and thawing, typically at levels between about 0.5
and 10% by weight of the egg whites. A preferred level is
between about 2 and 4~ by weight of the egg whites.
It is also possible, although not critical, to
include proteolytic enzy~es or other additives in the egg
yolk portion as described in U.S. Patent 3,510,315, although
such an additive can be omitted entirely.
The yolks and whites are placed in separate
containers and heated. Although the exact type of apparatus
or equipment used in the present process is not critical
relative to practice of the present invention, a preferred
container for heating is to place the yolks and whites in
flexible containers or bags for immersion in the cocking baths.
This permits easy transfer of the yolks and whites through the
heating and freezing steps, followed by easy removal of the
frozen yolks and whites from the containers prior to chopping.
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Heating of the yolXs and whites is carried out in a hot water
or steam bath at a temperature of between about 165 - 210F.,
preferably 170 - 185F. for a period of time sufficient to
coagulate or effectively cook the egg yolks and whites-to a
substantially firm texture and depending on the size of the
container,typically about 30 - 60 minutes.
The heated or cooked yolks and whites are then
removed from the cooking bath and cooled to facilitate rapid
freezing either by spraying with cool water or dipping the
.containers into a cool water bath. The heated whites and
yolks are then frozen as quickly as possible to a product
temperature of about 22 - 30F.
After freezing of the product to the above temperature,
the flexible containers with the frozen yolks and whites are
briefly warmed to permit easy removal of the frozen yolks and
whites from the containers as an integral mass for chopping.
This brief period of warming to permit removal from the container
does not appreciably alter the temperature of the frozen yolks
and whites from the desired range of about 22 - 30F.
The separately cooked, frozen yolks and whites
at a temperature range of 22 - 30F., preferably 24 - 28F,
are then chopped by simultaneous or sequential feeding of the
frozen yolks and whites to a mechanical chopping or cutting
device to quickly subdivide the yolks and whites into small
particles. It is not critical to the practice of the present
process at what weight ratio the yolks and whites are combined
during chopping and any weight ratio of whites and yolks may
be used. A preferred weight ratio for the chopped egg product
is 30 - 40 parts of yolk to 70 - 60 parts of white. An
especially preferred ratio is about 30 parts of yolk to 70
parts of white since this weight ratio somewhat approximates
the ratio of white to yolk normally found in whole eggs. Chopping
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may be carried out in any type of food cutter or similar
device provided the temperature of the product during
chopping does not rise above the noted temperature range
by excessive heat gereration during chopping. - .
The ch~pped, cooked egg product is then rapidly
refrozen as a mixture even though only partial thawing
on the surfaces of the yolks and whites has taken place
during chopping. The chopped product is best frozen while
in particulate form before being placed in a container.
lQ A preferred, though non-limiting means for quick freezing
the chopped yolk and white mixture is by using an individual
quick frozen system of any type for quick freezing of the
partic~late yolks and whites.
The resultant product, because of separate
cooking of the yolks and whites, has no discoloration
from contact between the two and has a uniform, bright
yellow color with separate and identifiable pieces of egg
white. The particles of chopped white and yolks are rela-
tively uniform without significant pasting or smearing of
the yolk over the surfaces of the egg white particles.
The diced product is highly suitable as a condiment for food
stuffs such as salads and represents a significant improve-
ment over similar condiments prepared from cooked shell
eggs.
The following Examples will serve to illustrate
the present invention by a description by specific embodi-
ments thereof.
Example 1
To 56 lbs. of pasteurized liquid egg whites is
added 8% by weight of modified food starch with the trade-
name, "Consista", manufactured by A.E. Staley, Decatur,
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Illinois, and mixed. The liquid egg white containing the
starch is proportioned in sausage type casings in about
2 lb. quantities. The bags are sealed and attached to a
continuous conveying system for cooking and freezing. -
The separated yolks and whites are cooked at aproduct temperature of 175 - 180F. in a water bath for
about 45 minutes until the yolks and whites are coagulated
to a firm texture. The bags containing the coagulated
yolks and whites are conveyed through a water spray of
10 . -cool water at 70 - 75F. and cooled.
. ..
The coagulated yolks and whites are then placed
in a freezer and frozen to a product temperature of 22 -
30F
The yolks and whites are removed from the flexi-
ble bags by brief thawing of the surface.of the mass of
frozen yolks and whites. 30 parts by weight of the frozen
yolks and 70 parts by weight of the frozen whites are placed
in a batch type cutting device consisting of a rotating
bowl and a set of vertically rotating, high speed cutting
blades. The yolks and whites are then chopped for a
period of 3 minutes.
The chopped egg product is then refrozen before
packaging by being passed through an individually quick
frozen system to quick freeze the particles.
The egg product after chopping and freezing, has
no significant smearing of the yolks on the particles of
egg whites and consisted of relatively uniform and distinct
pieces of yolks and whites. The chopped product lS highly
suitable as a condiment for foodstuffs.
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Example 2
12 lbs. of liquid egg white is placed in flexible
plastic bags in 1 lb. portions and sealed. The bags
containing the liquid egg whites are placed into a wat-er
bath at a temperature of 185F. for 20 minutes in order to
coagulate the egg white. Separately, 12 lbs. of liquid egg
yolk is placed in separate flexible plastic bags in 1 lb.
portions and sealed. The containers containing the yolks
and whites are placed in a water bath at a product temperature
10", -of 185F. for 20 minutes in order to coagulate the yolks
.....
and whites to a substantially firm texture. The coagulated
yolks and whites are then placed in a freezer and frozen to
a product temperature of 0F.
To illustrate the importance of the temperature of
the frozen product in chopping of the yo~ks and white,s, 12
lbs of cooked, frozen whites and 12 lbs. of cooked, frozen
yolks were tempered in cold water until they reached a
temperature of 35F. The yolks and whites were removed from
their containers and placed in a cutter of the type described
in Example 1 and chopped for 1 minute. The thawed whites
and yolks both lost their identity during chopping and the
yo~ks significantly smeared on the particles of egg white.
The smeared product was also difficult to refreeze since
significant clumping of the chopped egg product took place.
A 1 lb. portion of the cooked, frozen whites and
a 1 lb. portion of the cooked frozen yolks, each at a
temperature of 0F. was removed to a freezer at 20F.,
where the product temperature was allowed to equilibrate
to 20F. The yolks and whites at 20F. were then placed in
a water bath and adjusted to a product temperature of 26F.
The yolks and whites were removed from their respective
containers and placed in a cutter of the type disclosed in
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Example 1 and chopped for 1 minute. The yolks and whites
chopped into distinct separate pieces without significant
smearing of the yolk on the particles of egg white. The
chopped egg product could also be easily frozen without-
undesirable clumping of the product.
A 1 lb. portion of the cooked frozen whites and a
1 lb. portion of the cooked frozen yolks at a temperature of
0F. Flaced in a freezer at a temperature of 20F. where the
product temperature was allowed to equilibrate to 20F. The
1~ -yolks and whites were removed from their respective casings
by brief warming and chopped in a cutter for a period of 1
minute. The yolks and whites splintered during the chopping
procedure creating long irregular fragments of product, with
a significant amount of fines.
Having described the above invention with reference
to these specific embodiments, it is to be understood that
numerous variati~ns can be made without departing from the
spirit of the invention and it is intended to include such
reasonable variations and equivalents within the scope of
the present invention.
