Note: Descriptions are shown in the official language in which they were submitted.
2700~
E~OZEN RA~ CUSTARD
~he p:r~sent inv~-tion relates to a unique reezable raw custard and
use of such custard în ~he preparation of frozen raw quiche fillings and
other frozen custard fill~ngs.
For purposes of the present application, the terrn ~custard" is
defined as a mi~ or milk derived oonposition containing a substantial whole
egg portion or egg white based whole egg xeplacer. The custard of the
prasent invention p~eferably is essentially fat-free, e~luding egg fat, and
is starch-free.
.~
BACK~UND OF THE PRESENq INVENTION
A typical custard formllation, used aq a control for the present
~nvention, conprises whole miL~s, eggs, flour, salt and pepper. ~ether ~weet
or savory, it is thickened ~y the coagulation of the egg pr~tein. Desirably,
the custard proportion should be su~h as to produce a cutable texture fr~e of
. gummmess or graininess.
; Previous work with frozen eggs and e~g prcducts ha~ shown that
cobked egg protein is no~ st~ble to ~reezing and thawing. In particular,
toughness and excessive syneresis i5 exhibited by e~g custards which are
cooked prior to freezing and rewarmæd suksequent to being frD~en. m e
effect of the syneresis is a tendency on the part of the end product to
flatten out and release fluid on standing. Sugar in the custard co~pcsition
may serve as a somewhat protective agent, and sweet custards respond better
to post-ba~e freezing then savory ones. However, excessive weaping ca~ still
be noticed.
Freezing prior to baking results in a higher quality end product
but several drawbacks still remain. Freeze-thaw cycling still tends to
damage the raw egg protei~s ~y ice crystal grYwth and by creating micro-
enviromental changes; that is, eutectic muxtures with high-electxolyte (
ll 1168100
27005
concentrations which can denature the proteins. ~his damage will still
result in scme syneresis after baking and a loss of custard strength.
In addition, conventional cust~rd compositions do not lend themselves
to continuous manufacture on autom~tive preparation and filling lines,
S particularly in the case of quiche preparations which will contain particulate
solids, m addition ~o the custard ingredients, ~uch as neat solids, cheese
solids, vegetable solids, fruit solids, or seafood solids and the like~ mis
is because the raw custard is too thin to suspend such solids resulting in an
uneven distri~ution o ~he par~iculate~ in the end product. In addition,
excessive splashing i5 likely to occur in mechanical filling operations.
The use of gums, including natural gums or cellulosic gums to
prevent the syneresis of milk or milk derived compositions is well known.
For instance, prior Patent No. 3,721,571 to Glick~man et al describ~s a
pudding con~osition which exhibits resistance to syneresis under condi~ions
of freeze-thawing or high heat treatment. The composition co~prises water,
s~eetening agents, fat emulsions, milk solids, starch and gums, an amount of
the gum being xanthan gum. The pudding compcsition doe s not contain whole
eggsO Stabilizing is acco~plished by the starch/gum combination.
Prior Patent No. 3,911,144 to Strong et al describes a liquid egg
product purporting to have a higher degree of freeze-~haw stabilit~ co~prising
an amount of egg ~hite, nonfat dry milk solids, and ~ther ingredients. ~ere
again, an amount of ~an~han gwm is e~ployed to i~part freeze-~haw sta~ility
to the liquid egg prcduct~ A substantial am~unt of the product is a vegeta-
ble fat, and the proportions of ingredients are said to be such as to produce
a product which has the organoleptic charactexistics of whole eggs, suitable
for such applications as the preparation of baked gDods. Only eggs whites
~ axe employed in the product~
Patent No. 3,993,793 to Finney is typical of tho.se patents employing
a micrw ~ys-talline cellulose as a stabilizer for ice creams and frozen
~ 8 1 0 ~
confections. ~le compositions do not contain a substantial egg content.
Another recently issued patent in this art is Patent No. 4,216,242 to
Braverman.
Prior Patent Nos. 3,345,185, to Pisani et al and 3,510,316, to
` Decker, are typical of low-fat formulations usable in the preparation of
; frozen deserts. The formulations do not suggest the present invention.
SU~MARY-~F THE INVENTION
According to the present invention, there ls provided a frozen,
uncooked raw custard preparation, a substantial proportion of which is whole
egg or egg white based whole egg replacer, capable of withstanding freeze-
thaw cycling, and capable of homogeneous suspension of food particulates
prior to freezing, comprising
1) an organloeptically effective amount of said food particulates;
2) uncooked, whole egg or egg white based whole egg replacer;
and
3~ a milk-derived portion
wherein said egg and milk-derived portion are present in the weight ratio
of about .45:1 to about .75:1;
the milk derived portion comporising fluid milk, a thixotropic
gum, and a water-absorbing quantity of a protein concentrate, in proportion
to provide with said whole eggs or egg replacer a viscosity sufficient for
homogeneous suspension of said food particulates prior to freezing, the
protein content by Kjeidahl analysis from the fluid milk and protein concen-
trate being at least about 4% by weight of the milk derived portion.
In another aspect, the invention also provides a frozen, uncooked,
egg~based raw custard preparation, capable of withstanding freeze-thaw cycl-
ing and capable of homogeneous suspension of food particulates prior to
freezing, comprising
1) an organoleptically effective amount of said food parti-
culates;
2) uncooked whole egg or egg-white based whole egg replacer;
.,. ~
. ~' ' ,~
~8~0~
3) a milk-derived portion, items 2) and 3) being in relative
amounts to yield on cooking a custard-like consistency;
the milk-derived portion comprising
a) a thixotropic gum thickening agent;
b) a protein concentrate; and
c) fluid milk, the amount of gum thickening agent being
sufficient with other ingredients of the formulation to achieve suspension
of the food particulates in the formulation prior to freezing~
` Preferably, the fluid milk is formulated from water and nonfat
`~ 10 dry milk solids to provide a solids content comparable with fluid milk.
`i Preferably, the milk derived portion consists essentially of
about 82-84% water; about 8-10% nonfat dry milk solids; about 4.5-8.0~
water absorbing bland protein concentrate, about ~5-1.75~ thixotropic gum,
and effective amounts of flavors and seasoning components.
.
3a~
1~6~
Preferred embodiments are those wherein the water absorbing
protein is a whey protein concentrate and the gum is a thixotropic cellu-
lose derivative. A water dispersible microcrystalline cellulose is a
preferred gum.
Following freezing and then cooking, for instance by baking,
; the product of the present invention exhibited the texture, flavor and
- appearance of unfrozen baked egg custard. AEter at least four freeze-thaw
cycles, the product showed no discernable significant weeping.
An advantage of the present invention is that the custard base
is readi]y adaptable to a number of difierent quiche formulations, for
instance a Quiche Lorraine, Quiche Alpine, Quiche Napoli, and Quiche
Francais. The food particulates can be, by way of example, meat solids,
cheese solids, vegetable solids, fruit solids, and seafood solids, and
combinations thereof.
After an extended period of time, for instance nine months,
at 0F. or below, all products were judged acceptable. At the same time,
the custard compositions were readily adapted for use with automatic pro-
cessing and filling lines, and had a uniform distribution of particulate
matter therein
DETAILED DESCRIPTION OF T~IE
PRESENT INVENTION AND_E~AMPLES
In practice of the present invention, the microcrystalline
cellulose and water are first intensively mixed using a high-speed mixer,
and this mixture along with other liquid ingredients such as liquid flavor-
ants (e.g., wine, tomato sauce) and excluding the eggs, are then placed in
a suitable mixer, for instance a Hobart mixer. Other water dispersible
liquid flavorants or colorants can be added at this point. The dry ingredi-
ents, namely the non~fat dry milk, protein concentrate, and any dry Elavor
and seasoning ingredients are then added to the liquid mixture in the mixer,
and the combination is mixed thoroughly. Completely thawed, frozen whole
eggs or egg white based whole egg replacer are then added to the above
mixture and blending is continued for an additional short period of time.
-4-
,''' ~
8~0~
At this point, or after the blending of the dry ingredients7 the food
particulates, for instance meat particulate, vegetable particulate, cheese
particulate, fruit or seafood particulate, or the like, can be added. The
entire mixture is then dispensed into an unbaked pie shell, which is in
turn in a suitable container, is covered, and then frozen. For consumption,
the frozen quiche is baked at about 375F. for about 60 minutes.
Following mixing, but prior to freezing, the products of the
present invention have a viscous consistency or viscosity sufficient for
homogeneous suspension of particulate solids therein, and to prevent
splashing in automatic dispensing apparatus.
Effective results are obtained with a viscosity in the range
of about 3,000 to about 5,000 centipoises as determined on a Brookfield
Rotational Viscometer, Model LVF, taken after one minute using spindle
No~ 2 at a speed of 30 rpm (at 75F).
The custard portion of the products of the present invention
was also tested for syneresis before and after freeze-thaw cycling, for
baked custard gel strength before and after cycling, and for organoleptic
evaluation of appearance, mouthfeel and flavor relative to a conventional
custard control. Syneresis was measured by allowing the baked custards
to cool for 15 minutes, inverting them on a screen (ASTM No. 40), and
weighing the amotmt of fluid accumulated beneath the screen after one hour.
Samples were covered to prevent evaporative loss. To evaluate gel strength,
baked custards were cooled and the surface skins were carefully removed.
A Precision Scientific Bloom Gelometer is used to determine the weight of
lead shot neceSsQry to propel a gelatin testing plunger 4 mm into the sur-
face of the custard.
In all cases, the custard products of the present invention
showed no significant, ascertainable syneresis, exhibited excellent gel
strength and excellent organoleptic characteristics (appearance, mouth-
feel and flavor) relative to a control. Again, control is a standard
custard made from eggs, milk, four, salt and pepper.
Preferably the custard preparation of the present invention
--5--
,
/,,,
, . .
~ :~B8 ~0 ~
employs whole eggs. A replacer for whole eggs can be used but should be egg
white based. A number of such replacers are marketecl commercially, such as
Creme-o-fluff (Trademark, Holton Food Products Co.), which is essentially
fat-free. Another such replacer is that disclosed in Strong et al patent
~o. 3,911,144, which is egg white based and contains a vegetable oil and
anti-oxidant for stability.
The use of non-fat dry milk solids in the composition of the pre-
sent invention is important to prevent rancidity of the product due to in-
stability of milk fat during the freezing period. In this regard~ the
composition of the present invention preferably is essentiallq fat~free
(exclusive of the eggs) and preferably contains no vegetable fat. The non-
fat dry milk solids, when added to water, provides a milk replacer and is
the primary dairy ingredient of the present invention. By "fat-free", it is
meant that the only fat in the present formulation is that incidentally pre-
sent in the non-fat dry milk solids or other ingredients, e.g., eggs, in the
formulation. Skim milk may be employed as the primary dairy ingredient in
place of non-fat dry milk solids. In such case, the water content would
have to be appropriately adjusted or eliminated. Alternatively, a casein
derivative such as sodium or calcium caseinate can be employed, on a protein
equivalency, as the milk solids.
Quiche products in accordance with the present invention have been
successfully made employing whole milk to provide the milk solids. The
whole milk is used at a level to provide a protein content equivalent to
that of non-fat milk solids in the above Eormulation. However, an amount of
antioxident is required to prevent rancidity over long storage. While milk
products provides a richer mouthfeel which may or may not be preferred~ One
can also employ a dairy product such as half-and-half or cream as a part of
the dairy portion or, alternatively, a non-dairy coffee creamer. One suit-
able creamer is Coffee Rich, (Trademark Rich's Products). Another is
Coffeemate, (Trademark Carnation Company), having a label declaration in-
;~ cluding corn sqrup solids, partially hydrogenated coconut oil, sodium case-
inate, and mono- and diglycerides. With the use of fat containing milk
, ,
1 0 ~
; products, adjustment of the amount of gum employed may be necessary. For
` instance, with use of whole milk, the microcrystalline cellulose may be used
at a level up to about 2-1/4% based on the weight of the composition milk
portion. The microcrystalline cellulose may~ in such case, advantageously
be supplemented with use of a small amount of another gum,such as carrageenan.
For purposes of the present application, the term "fluid milk" when
used herein shall include natural milk, skim milk and reconstituted milk
from milk derived solids (e.g., non-fat dry milk solids and water).
The gum stabilizer can broadly be any thixotropic gum which is com-
patible with the egg structure of the present Eormulation, in the sense that
the gum gel has a similar strength and mouthfeel to that of egg protein, and
which is capable of hindering breakdown of the egg protein structure (capa-
ble of inhibiting ice crystal growth)~ The gum stabilizer also aids in
suspension of the particulate solids.
A preferred such gum is a medium to high viscosity, microcrystal-
line cellulose. Other cellulose derivatives which may be employed in the
present invention and are thixotropic are methylcellulose, carboxymethyl-
cellulose, hydroxypropylmethylcellulose, and sodium carboxymethylcellulose.
~ icrocrystalline cellulose is a well-known industrial product, and
~O is frequently used in low-calorie ice creams at relatively high levels. To
make it readily dispersible, it is solcl combined with sodium carboxymethyl~
cellulose under the Trademark Avicel, such as Avicel RC-591 (FMC Corporation)
and Avicel CL 611. These compositions are stated to be colloidal forms of
microcrystalline cellulose which have been blended with sodium carboxymethyl-
cellulose and dried. In Avicel RC-591, the amount of sodium carboxymethyl-
cellulose is about 1l~ + 1~ by weight of the microcrystalline cellulose.
~ ther gums which may be used alone or in combination with the cel-
lulosic derivatives, to provide thixotropy and meet the other requirements
listed above, are plant extracts such as acacia gum and karaya gum; marine
plant extracts such as algin and carrageenan; seed extracts such as
:, '
,'
~7-
guar gum and fruit extracts such as pectin~
The water-absorbing protein concentrate of the pre.sent in-
vention preferably is compatible in flavor with the dairy system. A pre-
ferred such protein concentrate is whey protein concentrate which is milk
derived and in this respect useful as a supplementary dairy component.
A particularly preferred such protein concentrate is HiSorb (Trademark),
a milk protein marketed by Stauffer Chemical Co. It is a partially
; delactosed non-fat dry milk which is capable of absorbing large amounts
of water. These whey solids also set to an egg-protein like gel on heat-
ing, thereby augmentlng the structure of the primary stnlctural ingredient
(eggs). Although the protein concentrate preferably is bland in flavor,
so as to not adversely affect the flavor of the end product, this is not
; necessary if certain masking flavors are present. Examples of other water-
absorbing protein concentrates that can be used are soy protein concentrate,
soy protein isolate, whey soy protein blends, fish protein concentrate, and
egg albumin.
Starch is a well-known water absorbing food additive, but its use
in the present invention adds a starchy undesirable texture to the final
product. It is an aspect of the present invention that the formulation
thereof is starch-free.
; The proportions of ingredients employed can be widely varied.
For instance, the amount of non-fat dry milk solids (or skim milk, whole
milk, caseinate, etc.) and water absorbing protein concentrate may be
varied in level to provide a total protein content (by Kjeldahl analysis)
of at least about ~% by weight oE the milk derived portion. The amount
of milk solids present, whether from liquid milk or reconstituted from
mi.lk derived solids, should be sufficient to provide the desired level
of milk flavor in the end product. Generally, at least about 8% milk solids
is a flavoring amount necessary in the milk derived portion to get a milk
flavor.
Milk solids are about 35% protein, the remainder being primarily
810~
ash and carbohydrate. Thus, 8% solids contributes about 2.8% protein to the
milk derived portion. If a soy caseinate protein concentrate is used as the
concentrate, it may have a protein content as low as about 30%. Generally,
at least about 4.5% concentrate is necessary to obtain the water adsorption
required, Soy caseinate at a level of about 4.5% will thus provide at least
about 1.35% protein, giving a total protein content of more than 4%. Soy
protein isolate can be about 90% protein, giving an even higher total pro-
tein content.
The amounts of flavoring, seasoning, colorants and food particulates
added should be those necessary to obtain the organoleptic characteristics
required, particularly appearance, flavor and texture. Amounts of sugar or
other such carbohydrate may be employed as needed or desired.
Sweetening agents, in addition to sucrose which may be employed in
~ the custards of the present invention, include dextrose, lactose, fructose,'~
corn syrup solids, and similar carbohydrates added to a sweetness level de-
sired. Functionally, particularly with the use of such sweetening agents as
`~ corn syrup solids, the sweetening agents may desirably add some stability to
the end product. Low-calorie custards may also be prepared by employing syn-
thetic sweetening agents preferably in combination with a low-bulk density
carbohydrate filler (such as Avicel PH-101, Trademark F~IC Corporation)
The following examples are illustrative of the present invention~
The formulas below were employed to produce manufactured frozen quiche fillings.
EXAMPLE I: Quiche Lorraine Filling
Milk Portion: 43%
v~ Water 83.0
Nonfat dry milk 1 9 5
Water absorbin~ protein concentrate 5.5
Gum stabilizer 1.0
: Seasonings balance
Liquid Whole Eggs: 23%
Food Particulate: 34%
Cooked bacon 23.5
Chopped cheeses 76.5
1 HiSorb Concentrate, Stauffer Chemical Co~
2 Avicel RC-591, FMC Corporation
EXAMPLE II: Ouiche Francais Fllling
Example IT is substantially the same as Example I, except that
the milk portion contains 74% water and 9% whice wine. Also, the amount
of milk portion is reduced to about 34%, while the egg portion becomes
19% and the food particulate 47%. The food particulate is characterized
by roughly 44% cheese, 26% cut asparagus and 30% crab meat.
The above formulations were prepared by hydrating the gum stabi-
lizer in the water fraction using a high-shear mixer. The remaining
~ solids in the milk portion were then added and mixed thoroughly. In
; 10 Example II, the wine was added at this point~ Next, the food particulate
portion was dispersed in the mix. The eggs were added and mixed as a
final step. Fillings were held under refrigeration until use~ Measured
amounts of the finished, homogeneous fillings were mechanically~ deposîted
into previousl~ prepared pie crusts in appropriate containers. Quiches
were frozen in a blast freezer to an internal temperature of ~10F, and
packaged.
The above quiche were tested for performance (custard strength,
stabillty, and particulate distribution) and organoleptic characteristics
(flavor, mouthfeel, and appearance) against a control product ( a non-
ZO frozen cookbook quiche formulation subjected to conventional preparation
and baking procedures?. In organoleptic attributes, the example quiche
compared favorably with the standard. In performance characteristics,
the example products were superior to the control in all respects. Freeze-
thaw testing showed the products described above to be stable (exhibit no
appreciable syneresis) after four freeze-thaw cycles.
--10-
