Synergistic effect of ultraviolet radiation and high hydrostatic pressure on texture, color, and oxidative stability of refrigerated tilapia fillets

Abstract

BACKGROUND: The isolated application of high hydrostatic pressure (HHP) and ultraviolet-C (UV-C) radiation may induce physicochemical changes, thus jeopardizing fish quality attributes during refrigerated storage, which could be minimized by the use of synergistic treatments. Therefore, this study investigated the combined effect of UV-C at 0.103 ± 0.002 J cm −2 and HHP at 220 MPa for 10 min on quality parameters of tilapia fillets stored at 4 ∘ C for 15 days. RESULTS: HHP and UV-C+HHP showed higher myoglobin concentration, higher metmyoglobin-reducing activity, and lowera* than control and the UV-C treatment (P < 0.05), reaching 2.49, 2.58, 1.62, 1.54 mg myoglobin g −1 , 13.30, 13.81, 2.29, 2.29%, and 2.32, 2.58, 4.29, 3.98 respectively on the last day of storage. UV-C, HHP, and UV-C+HHP increased water-holding capacity and decreased the pH levels, hardness, and chewiness (P < 0.05). HHP retarded lipid oxidation and UV-C increased protein oxidation compared with control (P < 0.05), achieving 0.81 and 2.80 mg malondialdehyde per kilogram of fish tissue, and 5.50 and 4.15 nmol carbonyl per milligram of protein respectively on 15th day of the storage.CONCLUSION: Both technologies (alone or together) enhanced texture parameters and water-holding capacity. UV-C did not induce color changes and lipid oxidation, whereas HHP showed high potential to prevent meat discoloration, lipid oxidation, and protein oxidation. In addition, this combination of methods could be an alternative to prevent protein oxidation induced by UV-C. WHCIn all treatments, the WHC decreased as the storage period increased ( Table 2). The decrease in WHC during the storage time J Sci Food Agric 2019; 99: 4474-4481

Application of Active Packaging in Refrigerated Rainbow Trout (Oncorhynchus mykiss) Fillets Treated with UV-C Radiation

“…In agreement with our results, previous studies reported a decrease in a* values during refrigerated storage of rainbow trout fillets [30] and pirarucu fillets [39], and also an increase of b* values in pirarucu fillets [39] and tilapia fillets [8,9] under refrigerated storage. Also, similar to our results, Pedrós-Garrido et al [42] and Lee et al [43] observed that UV-C radiation at 0.19-0.38 J/cm 2 and 4.8 J/cm 2 enhanced meat discoloration by the decrease in a* values and increase in b* values in salmon fillets and semi-dried Pacific herring, respectively.…”

“…The increase of L* values as the increase of storage period was found in other refrigerated freshwater fish species [9,13,39], including rainbow trout [30]. Likewise, similar UV-C doses (0.10 and 0.30 J/cm 2 ) and O 2 scavenger, alone or in combination, did not affect L* values of tilapia fillets stored under refrigeration [8,9,13], corroborating with our results. Table 3.…”

“…The decrease in hardness and chewiness during the storage of fish is associated with protein degradation due mainly to the action of endogenous and microbial proteases [46]. Similar results of hardness and chewiness were observed during refrigerated storage of rainbow trout fillets for 9 days [30] and tilapia fillets for 15 days [8]. Moreover, oxidative reactions may induce texture changes; however, it is a very complex issue, which is not yet fully understood.…”

“…The differences between treatments may be explained by the same reasons as those mentioned for lipid oxidation in association with the fact that protein and lipid oxidation are concomitant reactions [8,28]. MDA from lipid oxidation can bind to amino acid residues into myoglobin and to some sites into myofibrillar proteins exposing it to the oxidizing environment and making it more susceptible to protein oxidation [29,37].…”

“…To overcome this challenge, the United Nations Food and Agriculture Organization [1] suggests studies concerning viable preservation technologies aiming to achieve a maximum shelf life without compromise the original quality parameters of fish, which is one of the most challenges for the scientific community and food industry by the use of a single method. In this way, studies about combined preservation treatments have increased [7][8][9][10].…”