Method of preparing an encrusted food product

An encrusted food product, such as a pizza roll, is prepared by co-extruding a cavity-forming sealant material, such as cheese, with a bread or pastry dough whereby the cavity-forming sealant material is encapsulated in the dough, subjecting the co-extruded article to a preliminary baking whereby the cavity-forming sealant material melts and generates gases. The molten material coats the interior of the encapsulating dough and the generated gases cause expansion of the space occupied originally by the cavity-forming sealant material thus creating a cavity or void within the dough. After preliminary baking the dough with its interior void lined and sealed with molten material is chilled to set the molten material. Thereafter the void or cavity of the dough so prepared can be filled with any desired filling and baking can be completed.

BACKGROUND OF THE INVENTION 
It has long been known that an elegant food dish can be obtained by baking 
various foods inside a pastry encapsulating crust. Beef wellington is an 
example. 
U.S. Pat. No. 4,721,622 (Kingham) describes preparation of a shelf-stable 
filled food product which has a bread casing and a filling. The filling is 
separated from the filling by an edible barrier layer. 
An edible barrier between pizza crust and other components such as tomato 
sauce is disclosed in U.S. Pat. No. 4,066,796 (McKee). The barrier 
minimizes migration of sauce into the crust thereby preserving taste and 
texture of the pizza product. 
Selleck (U.S. Pat. No. 4,348,949) also discloses minimized saturation of a 
bread product by providing the baked bread with a channel with a thick 
crust which holds a liquid food material and acts as a liquid migration 
barrier. 
Various edible food containers (e.g., ice-cream cones) rendered resistant 
to moisture from a food filling by applying a moisture-resistant fat to 
the interior of the container in U.S. Pat. No. 4,390,553 (Rubenstein). 
Accordingly, a need has existed for a means for preventing migration of 
moisture between various components of a food composition when one 
component is dryer than another component. This is particularly true for 
food products which are prepared days or weeks before the intended time 
for consumption and stored in frozen form. Modern production and 
distribution of convenience foods which can be ultimately prepared by the 
consumer with minimal final cooking time demands methods of production 
which will provide both ease of industrial preparation while still 
assuring an ultimate product of quality as close to freshly prepared as 
possible. 
Thus, it is an object of the present invention to provide a fast, 
convenient and effective method of preparing a filled food product which 
has effectively minimized moisture migration between components thereof. 
Another object of this invention is to provide a method for continuous 
production of all natural convenience foods (e.g., a pizza crust roll 
filled with pizza sauce and "toppings") which have an extended shelf life 
by virtue of effective minimization of moisture migration between 
components of the food product. 
These objects and other advantages of this invention will become more 
apparent from the following description and the details discussed therein. 
BRIEF DESCRIPTION OF THE INVENTION 
An encrusted food product having a pastry or bread encapsulating shell 
filled by a more moist food material with a sealing layer provided 
therebetween is prepared by the steps which comprise: 
a) co-extruding dough with a cavity-forming sealant material whereby the 
dough forms an encapsulation shell surrounding said material, 
b) subjecting the co-extruded article from a) to a temperature sufficient 
to at least partially bake the dough and to cause cavity-forming sealant 
material to melt and generate gases whereby the gases expand and create an 
open cavity within the encapsulating dough and the cavity is lined with 
molten material thereby providing a sealant for the dough exterior to the 
cavity, 
c) setting the molten material lining the dough cavity by cooling the 
article from b), and thereafter, 
d) providing the sealant lined cavity with a food sauce by injecting the 
sauce into the cavity.

DETAILED DESCRIPTION 
The method Which is the present invention begins with preparation of a 
dough and a cavity-forming sealant material which are co-extruded with the 
former encapsulating the latter. Preparation of dough from flour, yeast 
and other additives is well known in the art as are precise formulations 
to achieve a desired texture, consistency and taste of the ultimate baked 
dough. However, for the present invention it is preferred to use flour 
with a high gluten content which will confer the property of toughness and 
elasticity on the dough. Those properties are desirable so that when the 
cavity-forming sealant material produces gases during baking thereby 
causing expansion of the encapsulating dough, the encapsulation will 
remain sealed and will not burst. The most preferred dough is a 
conventional dough of enriched brominated bread flour with 14% balancer. 
The cavity-forming sealant material performs two functions in the present 
invention. At baking temperatures the material must be capable of giving 
off a gas which upon expansion causes creation of an open space within the 
encapsulating dough. Simultaneously, the material must become sufficiently 
pasty and molten at baking temperatures to coat and seal against moisture 
the open space formed within the encapsulating dough. It has been found 
that cheese obtained from dairy products is suitable for this purpose. For 
preparation of a pizza roll, the preferred cheese is a mozzarella cheese. 
Of course, mozzarella can be mixed with other cheeses, such as romano or 
ricotta. Also, if desired, the cheese can be mixed with additional 
materials to modify its taste and consistency. One particularly suitable 
cheese mixture serving as the cavity-forming sealant material for a pizza 
roll is a mixture of mozzarella cheese and tomato sauce. 
Cavity-forming sealant material can be encapsulated by dough in any 
suitable physical form and can be considered to be of a core/shell 
structure with the cavity-forming sealant as the core with the dough as a 
shape-conforming shell. Shapes such as spherical, tubular, square, 
rectangular or any other desired shape are suitable. The core/shell 
structure is preferred to be formed by co-extruding dough and 
cavity-forming sealant through known co-extruding devices. A suitable 
devise is a Rheon Cornucopia KN200 manufactured by Rheon Automatic 
Machinery Company, LTD., of Utsunomiya, Japan. 
The relative amounts of dough and cavity-forming sealant can be easily 
selected by one skilled in the art based on the desired overall exterior 
size of the ultimate core/shell structure and the size of the interior 
cavity desired. Accordingly, a wide range of proportions of dough to 
cavity-forming sealant are within the scope of this invention. For 
instance, if a thin crust of baked dough is desired, a smaller amount of 
dough can be used to encapsulate the cavity-forming sealant than if a 
thicker crust is desired. Similarly, if a relatively large cavity within 
the baked crust is desired then a larger amount of cavity-forming sealant 
is encapsulated in the dough, than if a smaller cavity is required. In 
other words, the amount of encapsulating dough defines ultimate bread 
crust thickness and the amount of encapsulated cavity-forming sealant 
determines the size of the cavity formed. These parameters can be easily 
adjusted by one skilled in the art to obtain the desired product. 
After the cavity-forming sealant is encapsulated with dough by 
co-extrusion, the resulting core/shell structure is subjected to 
conditions which will bake the dough and cause formation of an open cavity 
therein which is coated with a moisture sealant. Accordingly, it is 
preferred to first subject the raw core/shell structure to a proofing step 
wherein the dough is permitted to at least partially ferment and rise. 
Conditions for proofing are well known in the art and the conditions can 
comprise subjecting the core/shell structure to a temperature from 
slightly above room temperature to about 100.degree. F. for a time of 
about 15 to 60 minutes. After proofing the core/shell structure is baked 
under normal baking conditions of about 400.degree. to 600.degree. F. for 
up to about 15 minutes. Baking serves to create the cavity against 
moisture and convert the dough to bread. Thus, upon completion of the 
baking step, the product obtained is a hollow bread article with its 
hollow cavity lined with a moisture sealing barrier which in the preferred 
embodiment comprises mozzarella cheese. 
When the baking is complete, the hollow bread article is removed from the 
baking oven and allowed to stand at room temperature for a short time (for 
example, 5 to 30 minutes). Thereafter, the hollow bread article is cooled 
in a standard refrigerator (35.degree. to 50.degree. F.) to solidify and 
set the cheese moisture sealing barrier which lines the cavity within the 
baked dough. Cooling can require up to about an hour depending on the size 
of the hollow baked article. 
After the baked article is cooled and the moisture sealing lining the 
interior cavity is set, the cavity can be filled with any desired food 
filling. A wide variety of food fillings can be used but whatever filling 
is used, it is usually injected into the cavity of the baked article as a 
paste which can be more or less fluid and flowable. In the preferred 
embodiment of this invention, the food filling can be a tomato-based pizza 
sauce. In addition, more pizza cheese and conventional pizza topping 
materials can be added to the sauce. For example, the tomato-based pizza 
sauce can additionally contain mozzarella cheese, romano cheese, meat, 
onion, peppers, mushrooms and so forth. 
Injecting the food filling into the cavity of the baked article completes 
the preparation of the encrusted food product of this invention and that 
product is then ready for consumption. The moisture barrier between the 
food filling and the encrusting bread material, however, prolongs the 
quality of the product between the time or preparation and the time of 
consumption by preventing moisture migration from the food filling into 
the encrusting bread. This is a significant advantage in commercial 
preparation of encrusted food products with a uniform quality not 
withstanding different times from production. Also, the filled products 
can be frozen and stored for a long period of time without loss of product 
quality caused by moisture migration between the food filling and 
encrusting bread. 
The preferred embodiment of this invention is a method of preparing 
individual pizza rolls which is described in detail in the following 
example. 
EXAMPLE 
Pizza Roll 
I. A dough mixture is prepared from the following ingredients: 
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High Gluten Flour 83 pounds 
Semolina Flour 17 pounds 
Dry Yeast 1.5 pounds 
Salt 1.0 pounds 
Dextrose 1.0 pounds 
Olive Oil 6.25 pounds 
Coloring 0.025 pounds 
Water 75 pounds 
S-500 Conditioner 1.25 pounds 
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II. A cheese-based cavity-forming sealant material is prepared with the 
following proportions: 
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Mozzarella Cheese 65% 
Romano Cheese 17.5% 
Ricotta Cheese 17.5% 
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The dough mixture (I) and the cheese-based material (II) are placed in 
separate hoppers of a co-extrusion machine such as a Rheon Cornucopia 
KN200 or 208 SD type manufactured by Rheon Automatic Machinery Co., LTD. 
of Utsunomiya, Japan. Pillow shaped portions of (I) and (II) are 
co-extruded with the dough entirely covering and encapsulating the 
cheese-based material. About 1.5 oz. of cheese-based material is 
encapsulated by about 3.75 oz. of dough and the size of each 
cylinderically shaped portion is about six inches by two inches in 
diameter. 
The co-extruded pillow shaped portions are then transferred to a proving 
and baking oven. The portions are subjected to a proving at about 
90.degree. F. for 30-40 minutes and thereafter baked at 
475.degree.-525.degree. F. for 5-10 minutes during which the cheese-based 
material melts and produces gases which expand to produce a cavity or void 
within the encapsulating dough which is of a size sufficient to hold about 
3/4 ounce of sauce filling. 
After removing from the baking oven, the portions are allowed to stand on a 
waiting rack at room temperature for about 30 minutes and then placed in 
standard refrigeration and cooled for about 1/2 to 3/4 hours. During the 
cooling, the melted cheese-based material which coats the interior surface 
of the dough cavity formed by the expanding gases sets and serves as a 
sealant between the baked dough and filler subsequently added to the 
cavity. 
When the cheese-based material sets, each portion is ready for filling. 
Each portion is moved into a machine which injects a predetermined amount 
of a tomato-based pizza sauce into the cavity. An injection machine such 
as a Rheon Injector 8 is suitable. The sauce contains: 
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Tomato Sauce/Tomato Paste (50/50) 
22.5 pounds 
Oregano 1 ounce 
Parsley 1 ounce 
Curry 2 ounce 
Sweet Basil 1 ounce 
Garlic 1 ounce 
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Each pizza-sauce filled portion is then frozen and packaged for commercial 
distribution as a pizza roll. The ultimate consumer completes preparation 
of the individual pizza rolls by crisping and warming in a conventional 
oven or in a microwave oven or by defrosting and heating in a toaster 
oven. If the packaging is to be for microwave warming, the individual 
rolls are packaged with a Mylar.RTM. crisper made by DuPont. Otherwise, 
for convection oven or toaster oven, any convenient packaging can be used. 
Having described the present invention, it would be readily apparent to 
those in the art that various changes can be made without departing from 
the invention and, as such, the invention is not limited by the example or 
the description in the specification but, rather, only as indicated by the 
following claims.