can form complexes with proteins (Park et al., 2007) and hence, the decrease of
TBARS partly contributed to the decrease of carbonyls with increasing
contents of NaNO2. This was confirmed by the significantly positive relationship
between protein carbonyls and TBARS (Table 1). Thiol groups
are extremely susceptible to hydroxyl radicals. The thiol groups can
change into sulfenic acid, sulfinic acid, and disulfide cross-links through
various complex reactions triggered by oxidation (Lund et al., 2011). Disulfide
cross-links are the principal reaction in the dimerization and polymerization
of myosin (Xiong et al., 2009). The loss of –SH with the
increase of NaNO2 indicated that NaNO2 could increase protein oxidation,
which is similar to previous findings (Sullivan & Sebranek, 2012;
Vossen & De Smet, 2015).