Food Lipids: Chemistry, Nutrition, and Biotechnology

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Lipid Oxidation of Muscle Foods
MARILYN C. ERICKSON
The University of Georgia, Griffin, Georgia
I. INTRODUCTION
Lipid oxidation is one of the major causes of quality deterioration in muscle foods
following storage at refrigerated or frozen temperatures. Often seen in later stages
of storage, quality losses are manifested through a variety of mechanisms, which are
summarized in Table 1 [1–17]. Although lipid oxidation usually causes a decrease
in consumer acceptance, in some cases lipid oxidation leads to enhancement of product
quality. An example is the enzymatic production of fresh-fish aromas. This chapter
reviews the fundamental mechanisms of lipid oxidation as they apply to muscle
foods. Included in this review is a discussion of the impact of tissue structure and
compositional factors on pathways, kinetics, and extent of oxidation. Also included
is a section describing the effect of various food processing applications on lipid
oxidation reactions. Throughout this chapter, the reader will be made aware of the
multiple interactions among muscle constituents during the process of lipid oxidation.
Therefore, a short review (Sec. III.G) details how mathematical models may be used
to account for these interactions and indicates how shelf life predictions and conditions
for optimal stability may be derived.
II. BASIC CHEMISTRY OF LIPID OXIDATION
The two major components involved in lipid oxidation are unsaturated fatty acids
and oxygen. In this process, oxygen from the atmosphere is added to certain fatty
acids, creating unstable intermediates that eventually break down to form unpleasant
flavor and aroma compounds. Although enzymatic and photogenic oxidation may
play a role, the most common and important process by which unsaturated fatty
Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.