Fundamental Food Microbiology, Third Edition - Fuad Fathir

CONTENTS
491
CHAPTER 36
Control by Modified Atmosphere
(or Reducing O–R Potential)
I. Introduction ..............................................................................................491
II. Objectives .................................................................................................492
III. Mechanism of Antimicrobial Action ........................................................493
IV. Influencing Factors ...................................................................................493
A. Nature of Process .............................................................................493
B. Nature of Foods ...............................................................................494
C. Nature of Microorganisms ...............................................................494
V. Methods..................................................................................................... 495
A. Vacuum Packaging ...........................................................................495
B. Gas Flushing ....................................................................................495
VI. Conclusion ................................................................................................495
References ............................................................................................................496
Questions ..............................................................................................................496
I. INTRODUCTION
Humans probably recognized in the early ages of agriculture and animal husbandry
that many foods were susceptible to quality loss when stored in air. This probably
led to the preservation of foods ca. 6000 B.C. by initially excluding air in pits and,
later, with the invention of pottery and baskets, in large vessels and containers.
Storage of grains, semidry products, some fermented products, concentrated syrups
and molasses, and similar products are still stored in large, closed, air-tight vessels
in many parts of the world to prevent insect infestation and the growth of molds and
yeasts. However, this method of changing the gaseous environment to preserve more
perishable products, such as fresh meat, fish, fruits, and vegetables and other