Effect of Refrigerated Storage on Fillet Lipid Quality of Rainbow Trout (Oncorhynchus mykiss W.) Fed a Diet Containing Different Levels of DL a-Tocopherol Acetate
The effect of refrigerated storage at 1 ± 0.3 ºC on vitamin E level, fatty acid composition and lipid oxidation of fillets was studied in 3 groups of rainbow trout fed diets supplemented with increasing levels (100, 300 and 500 mg kg-1 diet, respectively) of a-tocopherol acetate as antioxidant. Fish (initial mean weight 131 ± 1.0 g) were fed experimental diets for 58 days and reached a mean final weight of 299 ± 6.1 g, with growth differences among the 3 experimental groups being insignificant (P > 0.05). Fillet samples of fish were analyzed fresh (on day 0) or after storage at 1 ± 0.3 ºC for 9 days. Lipid oxidation was measured using the thiobarbituric acid reactive substances (TBARS) test. Dietary vitamin E levels had a significant effect on fillet a-tocopherol levels and TBARS values of fish by the end of 58 days of feeding. At the end of the feeding trial the fillet a-tocopherol levels of fish fed E100, E300 and E500 diets were 30.1 ± 0.2, 34.3 ± 0.1 and 40.1 ± 0.1 mg kg-1, respectively, and the fillet a-tocopherol levels were gradually decreased during the 9 days of storage at 1 ± 0.3 ºC (P < 0.05). However, at the end of the feeding trial the fillet TBARS values of fish fed diets were 4.4 ± 0.1, 4.2 ± 0.0 and 2.2 ± 0.0 mg malondialdehyde (MDA) kg-1, respectively, and the fillet TBARS values gradually increased during the 9 days of storage at 1 ± 0.3 ºC (P < 0.05). Dietary vitamin E levels did not influence the fatty acid composition of the fish fillets (P > 0.05). However, during the refrigerated storage period, total saturated fatty acid (SFA) concentration slowly increased and total polyunsaturated fatty acid (PUFA) concentration slowly decreased (P < 0.05). Finally, increasing the levels of a-tocopherol acetate in the diets from 130 to 580 mg kg-1 can slow down the level of lipid oxidation in fish fillets during refrigerated storage for 9 days at 1 ± 0.3 ºC.
Effect of Refrigerated Storage on Fillet Lipid Quality of Rainbow Trout (Oncorhynchus mykiss W.) Fed a Diet Containing Different Levels of DL a-Tocopherol Acetate
The effect of refrigerated storage at 1 ± 0.3 ºC on vitamin E level, fatty acid composition and lipid oxidation of fillets was studied in 3 groups of rainbow trout fed diets supplemented with increasing levels (100, 300 and 500 mg kg-1 diet, respectively) of a-tocopherol acetate as antioxidant. Fish (initial mean weight 131 ± 1.0 g) were fed experimental diets for 58 days and reached a mean final weight of 299 ± 6.1 g, with growth differences among the 3 experimental groups being insignificant (P > 0.05). Fillet samples of fish were analyzed fresh (on day 0) or after storage at 1 ± 0.3 ºC for 9 days. Lipid oxidation was measured using the thiobarbituric acid reactive substances (TBARS) test. Dietary vitamin E levels had a significant effect on fillet a-tocopherol levels and TBARS values of fish by the end of 58 days of feeding. At the end of the feeding trial the fillet a-tocopherol levels of fish fed E100, E300 and E500 diets were 30.1 ± 0.2, 34.3 ± 0.1 and 40.1 ± 0.1 mg kg-1, respectively, and the fillet a-tocopherol levels were gradually decreased during the 9 days of storage at 1 ± 0.3 ºC (P < 0.05). However, at the end of the feeding trial the fillet TBARS values of fish fed diets were 4.4 ± 0.1, 4.2 ± 0.0 and 2.2 ± 0.0 mg malondialdehyde (MDA) kg-1, respectively, and the fillet TBARS values gradually increased during the 9 days of storage at 1 ± 0.3 ºC (P < 0.05). Dietary vitamin E levels did not influence the fatty acid composition of the fish fillets (P > 0.05). However, during the refrigerated storage period, total saturated fatty acid (SFA) concentration slowly increased and total polyunsaturated fatty acid (PUFA) concentration slowly decreased (P < 0.05). Finally, increasing the levels of a-tocopherol acetate in the diets from 130 to 580 mg kg-1 can slow down the level of lipid oxidation in fish fillets during refrigerated storage for 9 days at 1 ± 0.3 ºC.
___
- Steffens, W.: Effects of variation in essential fatty acids in fish feeds on nutritive value of freshwater fish for humans. Aquaculture, 1997; 151: 97-119. 2. Scaife, J.R., Onibi, G.E., Murray, I., Fletcher T.C., Houlihan, D.F.: Influence of -tocopherol acetate on the short-and long-term storage properties of fillets from Atlantic salmon Salmo salar fed a high lipid diet. Aquacult. Nutr., 2000; 6: 65-71.
- Pirini, M., Gatta, P.P., Testi S., Trigari, G., Monetti, P.G.: Effect of refrigerated storage on muscle lipid quality of sea bass (Dicentrarchus labrax) fed on diets containing different levels of vitamin E. Food Chem., 2000; 68: 289-293.
- NRC (National Research Council): Nutrient Requirements of Fish. National Academy Press, Washington DC, USA. 1993: 114pp.
- Jensen, C., Birk, E., Jokumsen, A., Skibsted, L.H., Bertelsen, G.: Effect of dietary levels of fat, α-tocopherol and astaxanthin on colour and lipid oxidation during storage of frozen rainbow trout (Oncorhynchus mykiss) and during chill storage of smoked trout. Zeitschrift für Lebensmit.- Untersuch. und- Forsch., 1998; A 207: 189-196.
- Ostermeyer, U.: Fisch als Lebensmittel. Informationen für die Fischwirt. aus der Fischereiforsch., 1999; 46: 42-50.
- Kaushik, S.J., Gouillou-Coustans, M.F., Cho, C.Y.: Application of the recommendations on vitamin requirements of finfish by NRC (1993) to salmonids and sea bass using practical and purified diets. Aquaculture, 1998; 161: 463-474.
- Hamre, K., Berge, R.K., Lie, Ø.: Oxidative stability of Atlantic salmon (Salmo salar, L.) fillet enriched in α-, γ-, and δ-tocopherol through dietary supplementation. Food Chem., 1998; 62: 173- 178.
- Chaiyapechara, S., Casten, M.T., Hardy, R.W., Dong, F.M.: Fish performance, filet characteristics, and health assessment index of rainbow trout (Oncorhynchus mykiss) fed diets containing adequate and high concentrations of lipid and vitamin E. Aquaculture, 2003; 219: 715-738.
- Boggio, S.M., Hardy, R.W., Babbitt, J.K., Brannon, E.L.: The influence of dietary lipid source and alpha tocopheryl acetate level on product quality of rainbow trout (Salmo gairdneri). Aquaculture, 1985; 51: 13-24.
- Frigg, M., Prabucki, A.L., Ruhdel, E.U.: Effect of dietary vitamin E levels on oxidative stability of trout fillets. Aquaculture, 1990; 84: 145-158.
- Akhtar, P., Gray, J.I., Cooper, T.H., Garling, D.L., Booren, A.M.: Dietary pigmentation and deposition of α-tocopherol and carotenoids in rainbow trout muscle and liver tissue. J. Food Sci., 1999; 64: 234-239.
- Bai, S.C., Gatlin, D.M.: Dietary vitamin E concentration and duration of feeding affect tissue α-tocopherol concentrations of channel catfish (Ictalurus punctatus). Aquaculture, 1993; 113: 129-135.
- Tocher, D.R., Mourente, G., Van der Eecken, A., Evjemo, J.O., Diaz, E., Bell, J.G., Geurden, I., Lavens, P., Olsen, Y.: Effects of dietary vitamin E on antioxidant defence mechanisms of juvenile turbot (Scophthalmus maximus L.), halibut (Hippoglossus hippoglossus L.) and sea bream (Sparus aurata L.). Aquacult. Nutr., 2002; 8: 195-207.
- Ruff, N., Fitzgerald, R.D., Cross, T.F., Teurtrie, G., Kerry J.P.: Slaughtering method and dietary α-tocopheryl acetate supplementation affect rigor motris and filet shelf-life of turbot Scophthalmus maximus L. Aquacult. Res., 2002; 33: 703-714.
- Ruff, N., Fitzgerald, R.D., Cross, T.F., Hamre K., Kerry, J.P.: The effect of dietary vitamin E and C level on market-size turbot (Scophthalmus maximus) filet quality. Aquacult. Nutr., 2003; 9: 91-103.
- Lim, P.K., Boey, P.L., Ng, W.K.: Dietary palm oil level affects growth performance, protein retention and tissue vitamin E concentration of African catfish, Clarias gariepinus. Aquaculture, 2001; 202: 101-112.
- Ng, W.K., Lim, P.K., Boey, P.L.: Dietary lipid and palm oil source affects growth, fatty acid composition and muscle α-tocopherol concentration of African catfish, Clarias gariepinus. Aquaculture, 2003; 215: 229-243.
- Huang, C.H., Chang, R.J., Huang, S.L., Chen, W.: Dietary vitamin E supplementation affects tissue lipid peroxidation of hybrid tilapia, Oreochromis niloticus X O. aureus. Comp. Biochem. Physiol. 2003; B: Biochem. Mol. Biol., 134: 265-270.
- Bai, S.C., Lee, K.J.: Different levels of dietary DL-α-tocopheryl acetate affect the vitamin E status of juvenile Korean rockfish, Sebastes schlegeli. Aquaculture, 1998; 161: 405-414.
- Gatta, P.P, Pirini, M., Testi, S., Vignola, G., Monetti, P.G.: The influence of different levels of dietary vitamin E on sea bass Dicentrarchus labrax flesh quality. Aquacult. Nutr., 2000; 6: 47- 52.
- AOAC: Official methods of Analysis (16thEdition) Association of Official Analytical Chemists, Vols. I and II 4th Revision. Gaithersburg, Maryland, 1998.
- Huo, J.Z., Nelis, H.J., Lavens, P., Sorgeloos, P., De Leenheer, A.P.: Determination of vitamin E in aquatic organisms by high performance liquid chromatography with fluorescence detection. Anal. Biochem., 1996; 242: 123-128.
- Tarladgis, B.G., Watt, B.M., Younathan, M.T., Dugan, L.: A distillation method for the quantitative determination of malonaldehyde in rancid foods. J. Am. Oil Chem. Soc., 1960; 37: 44-48.
- Folch, J., Lees, M., Sloane Stanley, G.H.: A simple method for the isolation and purification of total lipids from animal tissues. J. Biol. Chem., 1957; 226: 497-509.
- Christie, W.W.: Lipid Analysis. Pergamon, Oxford, England. 1992.
- Zar, J.H.: Biostatistical Analysis. Prentice-Hall, Englewood Cliffs, NJ. 1984; 718 pp.
- WaagbØ, R., Sandnes, K., Torrissen, O.J., Sandvin, A., Lie, Ø.: Chemical and sensory evaluation of fillets from Atlantic salmon (Salmo salar) fed three levels of n-3 polyunsaturated fatty acids at two levels of vitamin E. Food Chem., 1993; 46: 361-366.
- Watanabe, T., Takeuchi, T., Masami, M., Ogino, C., Kawabata, T.: Effect of α-tocopherol deficiency on carp: VII. The relationship between dietary levels of linoleate and α-tocopherol requirement. Bull. Jpn Sci. Sci. Fish., 1977; 47: 1585-1590.
- Watanabe, T., Takashima, F.: Effect of α-tocopherol deficiency on carp: VI. Deficiency symptoms and changes of fatty acid and triglyceride distributions in adult carp. Bull. Jpn. Sci. Fish., 1977; 43: 819-830.
- Monnetti, PG., Gatta, PP., Trigari, G., Pirini, M., Testi, S.: Effetti dell’integrazione delmangime con vitamina E su alcune caratteristische qualitative della spigola (Dicentrarchus labrax). 1997; 405-406, Atti XII Congresso Nazionale ASPA, Pisa, 23-26 giugno.