Handbook of Meat Processing

231

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