3.6. Proteome characterization and protein identification
The sarcoplasmic and myofibrillar proteomes of catfish were
characterized to determine whether any differences existed between
the normal and red catfish fillets. During gel image analysis,
the protein spots (sarcoplasmic or myofibrillar) in normal and red
catfish fillets were detected, matched, and normalized for statistical
analysis. Gel images of myofibrillar (Fig. 1) and sarcoplasmic (Fig. 2)
proteomes in catfish were obtained after Coomassie Blue staining.
Statistical analysis of gel images (PDQUEST software, Bio-Rad)
revealed no differences (p > 0.05) in the myofibrillar proteome
For cooked catfish fillets, no differences (p > 0.05) existed between
normal and red fillets for salty and sour attributes. The red
fillets were less sweet and more bitter (p < 0.05) than normal fillets
(Table 3). No differences existed (p > 0.05) in hardness, which is in
agreement with instrumental tenderness measurements, but
normal fillets were juicier (p < 0.05) than reddish fillets. In addition,
red fillets were more oxidized, grassy, metallic/bloody, and
earthy, and exhibited more off-flavor (p < 0.05) than normal fillets.