Method for manufacturing a seafood product

Prefried, frozen food products, primarily seafood products are made in the form of a composite extrudate including a central core and an outer layer surrounding the core. The central core consists predominantly of coarsely ground seafood, such as clam meat, and the outer layer comprises the same seafood more finely ground and mixed with a binder. The extruded products suitably cut to length may be battered and breaded prior to prefrying and freezing.

BACKGROUND OF THE INVENTION 
This invention relates to food products, more particularly to prefried, 
frozen seafood products and the like, with particular reference to frozen 
clam and shrimp products. 
Prefried, frozen seafood products, such as shrimp and clam products, are 
becoming increasingly popular. In the case of prefried clam strips in 
particular, these are usually produced only from the foot or tongue of the 
clam (generally the surf clam) which is sliced into strip form, battered 
and breaded, prefried and then frozen. The body meat or salvage is 
generally not usable in such products. Due inter alia to catch limitations 
placed on the surf clam, there is a limited supply of tongues available 
for use in making prefried, frozen strips and the finished product tends 
therefore to be a restaurant "menu item" rather than a promotional "all 
you can eat" special. 
It is a particular object of the invention to provide a novel form of 
prefried, frozen clam product and a method of making same, whereby clam 
strips can be made using a greater percentage of the meat available from 
the clam as a whole. 
Another object of the invention is to provide a prefried, frozen clam 
product using comminuted (e.g., ground or chopped) clam meat. 
A further object of the invention is to provide a prefried, frozen clam 
product and method of making same from comminuted clam meat, which product 
simulates in its eating characteristics the heretofore described sliced 
clam strips. 
Still another object of the invention is to provide novel food products, 
particularly seafood and vegetable products, and methods of making same 
from comminuted primary ingredients. 
Yet another object of the invention is to provide a novel prefried, frozen 
food product and method of manufacturing same from a comminuted primary 
ingredient of animal or vegetable matter, whereby the finished product 
simulates in eating characteristics a similar product made from the same 
primary ingredient in strip form. 
SUMMARY OF THE INVENTION 
The invention provides, at least in one of its broader aspects, a prefried, 
frozen food product in the form of a composite structure having a central 
core and an outer layer surrounding the core, the core being formed of a 
first mixture consisting essentially of a primary ingredient of animal or 
vegetable matter in comminuted form and the outer layer being formed from 
a second mixture including the same primary ingredient as the core in 
comminuted form, and a binder, the mixtures having different 
characteristics respectively. 
In a preferred form of the invention, for example, the percentage by weight 
of primary ingredient in the core may be greater than in the outer layer, 
and the primary ingredient may be more finely comminuted in the outer 
layer than in the core. 
In the case of a frozen clam product, for example, the core may be formed 
from a mixture consisting predominantly of coarse ground clam meat, 
preferably surf clam but which may also comprise quahog, and a small 
percentage of a stabilizing additive or binder such as spun soya or soy 
protein. The clam meat may come from the clam foot, or tongue and/or the 
body. The mixture may, for example, contain about 95% clam meat by weight 
and about 5% additive. The clam meat may be ground or chopped to a 
particle size having a major dimension of about 3/8 inch. The other layer 
may be formed from a mixture comprising more finely ground clam meat (surf 
clam and/or quahog) and binder such as soy protein. The percentages by 
weight in the outer layer may be of the order of 75-80% clam meat and 
20-25% binder and the clam meat may be ground or chopped to a particle 
size having a major dimension of the order of 1/8 inch. 
Products as defined above may be manufactured in accordance with a further 
aspect of the invention, by providing the respective core and outer layer 
mixtures in slurry form and extruding the mixtures through a composite 
extruder head having a central extrusion orifice for the core, surrounded 
by an annular extrusion orifice for the outer layer. On passage from the 
extruder head, the product may be cut to approximately bite-size (11/2-4") 
random lengths, battered and breaded, then prefried, frozen in 
conventional manner and packaged. 
Apart from clam products, the invention may be used in the manufacture of 
other prefried, frozen seafood products, particularly shrimp products and 
vegetable products such as onion strips, by suitable substitution of the 
primary ingredient. 
Products in accordance with the invention simulate prefried, frozen 
products made from sliced strip and, particularly in the case of clams and 
the like, the inventive products can utilize a greater percentage of the 
meat available from the clam, and the finished product can therefore be 
made available more economically than the sliced strip products.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
FIG. 1 shows a prefried, frozen food product in the form of a composite 
extrudate 10 comprising an inner core 12 and an outer layer 14 surrounding 
core 12. Core 12 comprises a mixture consisting predominantly of a 
coarsely ground or chopped primary ingredient of animal or vegetable 
matter and a small amount of stabilizeer or binder. Generally, there may 
be just sufficient binder in the core to hold the primary ingredient firm. 
The primary ingredient may, for example, comprise clam meat (surf clam 
and/or quahog) chopped or ground into particles having a major dimension 
of about 3/8 inch. The binder may be spun soya or soy protein and the 
proportions of these ingredients may, for example, be of the order of 95% 
by weight clam meat to 5% by weight binder. 
Outer layer 14 may comprise a mixture of the same primary ingredient as the 
core, but more finely ground or chopped, and a binder. The percentage 
weight of primary ingredient in outer layer 14 is less than in the core. 
In the case of a clam product, outer layer 14 may contain about 75-80% 
ground or chopped surf clam and/or quahog and about 20-25% binder such as 
soy protein. The clam meat may in this case be ground or chopped to a 
particle size having a major dimension of about 1/8 inch. 
Alternative binders for use in the product may, for example, include 
mixtures of finely ground clam meat, juice and breading, and additives 
such as sodium chloride and tripolyphosphate may be included. 
The illustrated product is preferably enrobed in a conventional frying 
batter and the outer surface is preferably breaded. Typical dimensions for 
the product are: 
Diameter of core: .+-.1/4 inch 
Outer diameter of product: .+-.7/16 inch 
Length: 11/2-4 inches 
A method in accordance with the invention for manufacturing products as 
described above is diagrammatically illustrated in FIG. 2. 
Initially, slurries of the respective core and outer layer mixtures are 
formed and placed in respective storage containers or kettles. In the case 
of the core mixture for a clam product, a suitable slurry may, for 
example, be formed by mixing about 95 pounds of the coarsely ground or 
chopped clam meat with about 5 pounds of soy protein or like stabilizer or 
binder and about 5 pounds of water or clam juice. A suitable slurry for 
the outer layer may, for example, be formed by mixing about 75 to 80 
pounds of the finely ground or chopped clam meat with about 20 to 25 
pounds of soy protein or like binder and about 10 to 12 pounds of water or 
clam juice. 
From the storage kettles, the respective slurries are pumped in a chilled 
state to a composite extruder head having a central extrusion orifice 
through which the core is extruded and a surrounding annular extrusion 
orifice through which the outer layer is extruded. Composite extruder 
heads of this type are well known and need not be described in detail. The 
pumps may, for example, be positive displacement food pumps (e.g., Moyno 
pumps), the pressure through the extruder being determined inter alia by 
the speed of the pumps. Typically, for a 1/4 inch diameter inner extrusion 
orifice and a 3/8 inch diameter outer extrusion orifice, the extrusion 
pressure can be set in the range 5 to 15 pounds per square inch. 
On passage from the extruder head, the composite extrudate may optionally 
be sprayed with a stiffening agent such as calcium chloride, for example, 
if a stiffer outer coating is required. The extrudate may then be cut to 
random bite-size lengths, for example in the range 11/2 to 4 inches. 
After cutting, the extruded products may be enrobed with batter and breaded 
in a continuous flow, then instant quick fried in soy or other suitable 
frying oil at about 345.degree.-375.degree. F. for 5-12 seconds, frozen, 
for example, by nitrogen, carbon dioxide or in a mechanical freezer and 
suitably packaged. The products may, for example, be enrobed with batter 
and breaded on a conveyor, and moved by conveyor through a suitable fryer 
and freezer. 
As an alternative to the breading step described above, breading can be 
included in the outer layer mixture. Further, while process has been 
specifically described in relation to clam products, it will be understood 
that the process can be used for other products in the manufacture, for 
example, of extruded shrimp or onion sticks, by suitable substitution of 
the primary ingredient. 
The frozen products of the invention may be prepared for the table in 
conventional manner, for example, by further frying. In the finally 
prepared product, the outer layer serves to hold the comminuted primary 
ingredient in the core together and the consistency of the product is 
found to simulate that of a product made from a sliced strip of the same 
basic ingredient. 
While only preferred embodiments of the invention have been described 
herein in detail, it will be understood that the invention is not limited 
thereby, and modifications may be made within the scope of the attached 
claims.