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Chapter 12
Smoking
Zdzis ł aw E. Sikorski and Edward Ko ł akowski
Introduction
Smoking, drying, and salting of meats belong
to the oldest methods of food preservation.
Ages ago, meat hung above a fi re was pre-
served by the combined action of drying and
smoking, which was often preceded by pick-
ling in brine. Smoking extended the shelf life
and changed the sensory properties of the
meats. The procedures of smoking have been
gradually improved to suit the requirements
of people in different regions of the world in
respect to shelf life and sensory properties.
The role of the preservative effect of smoking
diminished in many countries, while fl avor-
ing and safety are of paramount importance
for the processor and consumer. Nowadays,
various smoking procedures are applied
throughout the world in rural households for
treating the meat and sausages for domestic
use, as well as in large processing plants for
the market. It is estimated that as much as
40% – 60% of the total amount of meats and
meat products are smoked.
The meats hung in a kiln are exposed to
smoke and heat for a time suffi cient to cause
the desirable sensory and preservative effect.
The smoke generally comes from smoulder-
ing wood chips or sawdust, either directly
below the hanging meat or in an external
generator. Its density, relative humidity, and
fl ow rate are controlled in a traditional
smoking oven by natural draft and depend on
the construction of the kiln, the weather con-
ditions, and the actions of the operator. In
modern, automatic smokehouses, the draft is
forced by mechanical equipment and shaped
according to a computer program adjusted to
the kind of smoked goods. The temperature
of the smoke affects the sensory properties
and the preservative effect, and controls the
rate of the process. Cold smoking takes place
in the range of 12 – 25 ° C and warm smoking
at 23 – 45 ° C. In hot smoking, since thermal
denaturation of the meat proteins is required,
the smoke temperature during various stages
of the process ranges from about 50 ° to
90 ° C.
In the past few decades, various aspects of
the process of meat smoking have progressed.
In traditional smoking, the most signifi cant
developments include:
- control of the composition of the smoke by
applying rational procedures of smoke
generation; - use of engineering principles regarding
heat and mass transfer to shorten the pro-
cessing time and control the weight loss of
the product; - optimization of the process parameters to
assure the required sensory properties and
safety of the smoked goods - modernization of smokehouses, which
affects smoke generation as well as han-
dling of the smoked material and control of
the process; and - treatment of the spent smoke to avoid pol-
lution of the environment.
In nontraditional smoking, various new
liquid smoke preparations have come into