Food Lipids: Chemistry, Nutrition, and Biotechnology

IV. EFFECT OF PROCESSING TREATMENTS ON OXIDATION
As foods are subjected to various processing treatments prior to storage, the opportunity
arises to modify their pattern of oxidation. Table 8 summarizes typical responses
exhibited by muscle tissue during storage following various treatments
[283–351]. Each of these treatments is covered in more detail in Sec. IV.A–IV.O.
A. Rinses
Chlorine rinses on muscle food constitute one processing step that could dramatically
alter the site to which lipid oxidation is directed. Chlorine rinses, based primarily on
sodium hypochlorite, are commonly used to reduce microbial loads in muscle foods.
Such rinses have led to incorporation of chlorine into beef, pork, chicken, and shrimp
[352–355] with phospholipids incorporating more chlorine per mole of lipid than
neutral lipids. Lipid chlorohydrins, formed by the reaction of HOCl with unsaturated
fatty acids [356], would likely disrupt the membrane’s physical organization and
reduce free radical chain oxidation of lipids [357]. This activity could be the basis
for the reduced development of warmed-over flavor in cooked and stored breast
patties prepared from chickens rinsed in a chlorine bath versus patties prepared from
nonrinsed chickens [358]. However, the capacity to form lipid chlorohydrins in tissue
samples would be diminished in samples having high concentrations of thiol and
amino groups because these groups display a much greater reactivity with HOCl
than unsaturated fatty acids [359,360]. Preferential scavenging of chlorine by thiols
and amino groups in dark chicken meat could account for the lack of significant
sensory differences in cooked and stored thigh patties prepared from nonrinsed and
chlorine-rinsed chickens [358].
Owing to health concerns about trihalomethanes and other chlorination reaction
products generated during interaction of organics and aqueous chlorine, efforts have
been made to explore alternatives. Chlorine dioxide has been one candidate; however,
Table 8 Typical Oxidative Response by Muscle Foods to Processing Treatments
Processing treatment Typical oxidative response Ref.
Rinses incorporating oxidizing agents Promotes 283,284
Washing Variable 285–287
Skinning Variable 34,288
Mincing Promotes 289–297
Salting Promotes 297–300
Curing Inhibits 301–305
Smoking Inhibits 306,307
Cooking Promotes 308–320
Deep-fat frying Promotes
High pressure Promotes 321–323
Vacuum drying Promotes 324,325
Irradiation Promotes 326–333
Glazing/edible coatings Inhibits 334–338
Freezing Inhibits 158,339–341
Packaging Inhibits 328,330,331,342–351
Copyright 2002 by Marcel Dekker, Inc. All Rights Reserved.