3.2. Biochemical lipid oxidation assessment
Frozen storage is known to be associated with fish lipid oxidation
processes where different kinds of endogenous enzymes
may be involved (Erickson, 1997). Freezing and thawing may cause
lysis of mitochondria and lysosomes and alter the distribution of
enzymes and factors affecting the rate of enzyme reactions in tissues,
so that deteriorative damage in frozen fish could be accelerated.
In the present experiment, different and complementary
biochemical lipid oxidation indices were employed to evaluate
the development of rancidity. Primary lipid oxidation was measured
by means of the CD formation and the peroxide content evolution
(Table 2), while secondary oxidation was evaluated by the
AV and the thiobarituric acid-reactive substances (TBARS) formation
(Table 3)