In the case of meat and meat products, the a* value is one of the most
important parameters to be evaluated. The higher the a* value, the
higher the red color observed, which is an important attribute from
the consumer's point of view. In the current study, samples treated
with LSLA solutions showed a* values significantly (p b 0.05) lower
than for other samples. The a* value for meat before treatment was
15.46 ± 3.97, which is higher than the values of the samples after marinating
and HPP. The use of marinade solutions and pressure caused
changes in the original red color of the meat (Table 3). Comparing the
samples after marinating, samples treated with LSLA solutions had
lower values of a* (p b 0.05). This result was not expected, since less salt and acid concentrations should cause less adverse effects on the
myoglobin, thus, it was expected that the HSHA treatment exhibited
the lowest value of a *. Regarding to HPP, Cava et al. (2009) noted that
discoloration caused by pressure processing appears as a result of oxidation
of ferrous myoglobin to ferric myoglobin with a decrease of a*
values. Oxidation also causes an increase in the proportion of
metmyoglobin (brown color) at the expense of oxymyoglobin (red
color). However, no difference (p N 0.05) was found in a* values
among samples subjected to different pressures (control, 300, 450 and
600 MPa) in this present study