Handbook of Meat Processing

Canned Products and Pâté 345

then a combination of convection and con-

duction, as explained before. Chili con carne

or “ chili ” is a spicy stew - like dish. The essen-

tial ingredients are, in addition to meat, chili

peppers, garlic, and cumin. It often includes

tomatoes, onions, beans, and other ingredi-

ents, as well.

Other products, such as luncheon meat

and p â t é , change their heating mechanisms

during processing, as they turn from semi-

fl uid to solid. P â t é is a product in which an

emulsion system turns into a gel.

Paste Products: Liver P â t é and

P â t é de Foie Gras

Meat paste products, such as p â t é , are similar

to emulsions. A true emulsion is defi ned as

two immiscible liquids, one of them being

droplets or fat globules (the disperse or inter-

nal phase) dispersed into another (the con-

tinuous phase); the droplet or fat globule

diameter in a true emulsion is between 0.1

and 100 μ m (McClemens 1999 ). Meat emul-

sions, however, also contain in the disperse

phase muscle fi bers, small connective tissue

fractions and carbohydrates, and the fat

droplet diameter of the disperse phase is

larger than 100 μ m; therefore, meat emul-

sions are not considered true emulsions, but a

“ paste ” or “ batter. ” When heated, the proteins

in the continuous phase gel, due to unfolding

and interlinking. This phenomenon stabilizes

the product. However, the high fat content

provides a smooth texture and spreadability.

On the other hand, foie gras, a French

term for “ fat liver, ” is a traditional product

fabricated only from the hypertrophied liver

of goose or duck; this hypertrophy is obtained

by supplying special diets to the animals. The

practice of force - feeding geese to enlarge

their livers dates back to at least 400 B.C.

Egyptian hieroglyphics depict slaves force -

feeding geese to enlarge their livers and

obtain a primitive foie gras. To obtain foie -

gras livers, animals are immobilized on farms

and fed with diets high in calories; the liver

large - format cans or lid blowing in glass jars.
In general, there are four systems, all using
steam as the heating medium: Sterilmatic ™ ,
Orbitort ™ , Hydrostatic ™ , and Hydrolock ™.
Sterilmatic ™ are Orbitort ™ are similar; the
cans are fed into the system through a pres-
sure seal, moving through the retort in a helix
conveyor that takes the cans through the
heating - cooling zones. Heat transfer is
increased by rolling the cans on rails.
After completing the thermal processing,
cans are cooled by cold - water spray or
immersion. This allows easier handling and
reduces the pressure inside the can. However,
water used for cooling must be sanitary, since
seam failures or microscopic holes (pinholes)
in the can allow water to enter into the food;
microorganisms present in the water can
grow and proliferate inside, causing sanitary
failures as well as other alterations such as
blowing. If cooling after heating is insuffi -
cient, thermophiles can grow. As a general
rule, canned meat products are cooled down
to 35 ° C. At this temperature, the can ’ s outer
surface cools rapidly (Guerrero Legarreta
2001 ).
Cans must be stored in small blocks
in well - ventilated areas to allow them to
reach room temperature at a fast rate.
Recontamination after heat treatment is a
very common problem, causing can blowing;
it indicates seam failure. The main microor-
ganisms responsible for this alteration are
cocci and bacilli (Ray 1996 ).

Canned Meat Products

Canned meat products include meat stews,
luncheon meat, sausages, sauces with meat
pieces, and paste products. These products
can be fully cooked before canning, as in the
case of sausages, or can be homogenous
products cooked inside the can, as in the case
of luncheon meat. Products such as “ chili con
carne ” ( “ peppers with meat ” ), sausages, and
sauces with meat pieces have solid and fl uid
ingredients in the can. The heat process is