The low a* and high b* values measured for meat samples
treated with DBD plasma could be attributed to the formation of
metmyoglobin during plasma treatment. Fr€ohling et al. (2012)
explained that hydrogen peroxide is generated during the treatment
of meat with plasma; this was because hydrogen peroxide
was previously detected in liquids treated with indirect plasma
(Oehmigen et al., 2011). Thus, the greenish color of plasma-treated
meat could increase because of the reaction between the generated
hydrogen peroxide and myoglobin. Furthermore, metmyoglobin,
whose high concentrations might increase the b* value of meat
(Brewer, 2004), is formed as a result of the oxidation of deoxymyoglobin
or oxymyoglobin (Mancini and Hunt, 2005). Increasing
plasma-exposure times might accelerate the aforementioned
oxidation process due to the formation of radicals and thereby increase
the concentration of metmyoglobin (Fr€ohling et al., 2012).