Handbook of Meat Processing

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Chapter 14

Novel Technologies for Microbial

Spoilage Prevention

Oleksandr Tokarskyy and Douglas L. Marshall

Introduction

Storage of chilled meats in air leads to
rapid spoilage by psychrotrophic bacteria,
predominantly Pseudomonas spp. and
Brochothrix thermosphacta. As shown in
Chapter 13 , traditional packaging systems for
meat products have been very successful in
slowing the rate of microbial spoilage and
extending the shelf life of meats. These
systems are designed to manipulate the gas
environment surrounding the product. Such
systems include oxygen - permeable overwrap
for short - term retail display to maintain
the bloom color of red meats. For long -
term storage, vacuum packaging (complete
removal of headspace gases) or modifi ed
atmosphere packaging (MAP)/controlled
atmosphere packaging (CAP) is employed.
The success of these packaging systems is
such that the majority of red meat produced
in the United States is vacuum or MAP pack-
aged (Siragusa et al. 1999 ).
In the present chapter we review a number
of recent non - thermal technological develop-
ments for the control of meat spoilage micro-
organisms and extension of shelf life. The
types of microbes found on meats and condi-
tions that lead to spoilage can be found in
recent reviews (Marshall and Bal ’ a 2001 ;
Nychas et al. 2007 ). We present here new
information related to revolutionary packag-
ing innovations such as gas scavenging and
antimicrobial impregnation systems. Also
discussed are recent developments in natural
product biological interventions (phage,

bacteriocins, chitosan, essential oils, and

enzymes), chemical interventions (organic

acid salts, acidifi ed sodium chlorite, phos-

phates, ozone, and electrolyzed water), and

physical interventions (ionizing irradiation,

high pressure, hydrodynamic shockwave,

pulsed electric fi elds, high intensity light, and

cold plasma). Brief commentary on novel

thermal processing interventions (high fre-

quency and ohmic heating) and novel carcass

decontamination methods is also provided.

Many of the interventions remain at the theo-

retical stage and will require extensive vali-

dation and economic analysis before practical

introduction to industry. Others, however,

have found widespread use and will likely

remain a mainstay in industry.

Packaging Systems

As introduced in Chapter 13 , several new

packaging systems have been developed that

hold promise to extend the shelf life of meats.

Traditional MAP/CAP usually involves

removal of headspace air, followed by rein-

troduction of gases that have a different

composition than air (Kerry et al. 2006 ).

Incorporation of elevated CO 2 levels into

packaging inhibits pseudomonads in chilled

meats (Marshall et al. 1991, 1992 ; Zhao et al.

1992 ). Complete oxygen removal by vacuum

packaging or 100% CO 2 /N 2 substitution

inhibits spoilage bacteria while favoring

growth of lactic acid producing bacteria,

resulting in extended shelf life of the product

(Nychas et al. 2007 ). The need for low