The major food preservation techniques that are employed are therefore all based
on a relatively limited set of factors, so that their range is necessarily limited also.
They are summarized in Table 1 in such a way as to highlight the Eact that most of
the techniques act primarily by slowing down or, in some cases, completely
inhibitin& microbial growth. The newer techniques, reacting to consumers’ needs,
include more natural approaches, (e.g., modified atmosphere packaging, use of
protective cultures, use of bacteriocins and other culture products and enzymes). In
contrast to the inhibitory techniques, few of the most widely used techniques act
primarily by inactivating the target microorganisms, indeed the only technique used
substantially for this purpose is still heating. However, it is interesting that most of
the newer or emerging techniques do act by direct inactivatioli, e.g., (al irradiation;
(b) the application of high hydrostatic pressure; (c) high voltage electric discharge
(electroporation); (d) ultrasonication combined with increased temperature and
slightly raised pressure (manothermosonication); and (e) addition of bacteriolytic
enzymes (lysozyme).