Fillet shelf-life of Atlantic halibut Hippoglossus hippoglossus L. fed elevated levels of α -tocopheryl acetate

Abstract

Fish fillet quality may be influenced by the antioxidant level in preslaughter diet. Thus, the effects of dietary a-tocopheryl acetate supplementation and feeding time on the flesh quality of farmed Atlantic halibut Hippoglossus hippoglossus L. were investigated. Halibut of mean initial weight of 312 + 12.3 g were divided into two groups and fed commercial diets, supplemented with different levels of a-tocopheryl acetate at the dietary inclusion levels of 189 and 613 mg kg À1 diet. Fish were sampled after 6,9,12 and 24 weeks. Over the experimental period, they reached a final mean weight of 1320 + 108.4 g. Tissue a-tocopherol of fillet and liver was significantly affected by the levels of a-tocopheryl acetate given with the diets (P < 0.001). In storage on ice, fillets of fish fed the diets high in a-tocopheryl acetate exhibited significantly lower (P < 0.001) levels of lipid oxidation. The colour of fillets in all groups deteriorated slightly, but diet did not affect this process. Halibut fed the supplemented diets for longer periods were better protected against lipid oxidation (P < 0.001) and colour deterioration (P < 0.01) than those fed for shorter periods. However, after 9 days of storage, lipid oxidation levels were still extremely low [< 0.6 mg malondialdehyde (MDA) g À1 fillet], even in fillets of fish fed the low a-tocopheryl acetate diet for a short period preslaughter. Different slaughtering methods tested at the end of the trial showed that percussive stunning can delay the onset of rigor mortis by 8±12 h compared with bleeding of the fish. These results suggest that halibut fillets have enhanced shelf-life stability even at low doses of dietary a-tocopheryl acetate, and that other factors in the antioxidant defence mechanisms of the species might play a major role in the prevention of lipid oxidation.

Effects of dietary propolis and vitamin E on growth performance and antioxidant status in blood of juvenile Rainbow trout, Oncorhynchus mykiss (Teleostei: Salmoniformes) under different flow rates

“…High vitamin E content in tissues would inhibit tissue lipid peroxidation (MURATA & YAMAUCHI 1989, FRIGG et al 1990, SAU et al 2004. Similar trends have been reported in rainbow trout (FRIGG et al 1990), turbot (STEPHAN et al 1995, sea bass (GATTA et al 2000), and Atlantic halibut (RUFF et al 2002). These reports indicated that the higher vitamin E consumption by the fish, the greater vitamin E concentrations in fish tissue, thus resulted in lower lipid peroxidation.…”

“…It is known that vitamin E show antioxidant characteristics to the oxidants in the cell membrane and another compound in the structure of propolis, caffeic acid phenethyl ester (CAPE), blocks the production of reactive oxygen types (SEVEN et al 2010, HOSNUTER et al 2004. Vitamin E (␣-tocopherol) function as biological antioxidants to protect cellular macromolecules (DNA, protein, lipids) and other antioxidant molecules from uncontrolled oxidation by free radicals during normal metabolism or under the conditions of oxidative challenge such as infection, stress, and pollution (HUANG & HUANG 2004, RUFF et al 2002. Survival of fish fed the vitamin E supplemented diets was higher in general.…”

Influence of Stress and Dietary Natural‐Source Vitamin E on Nonspecific Immunocompetence, Tissue Tocopherol Composition, and Postslaughter Fillet Oxidative Stability in Sunshine Bass

“…Fillet ctocopherol concentration was also increased at the highest level of NSVE supplementation, probably because minute amounts of this compound occurred as an impurity in the NSVE product used. Linear regressions of mean fillet a-tocopherol concentrations (standardized to fillet dry matter) versus as-fed dietary vitamin E concentration revealed diet-to-fillet transfer greater than reported for SYNE in other aquatic species (Stéphan et al 1995;Ruff et al 2002;Chaiyapechara et al 2003). The increased potency of NSVE is associated with superior binding of RRR-a-tocopherol to hepatic a-tocopherol transport protein (a-TTP) and therefore greater retention of RRR-a-tocopherol compared with its racemates or other tocopherol isomers (Stone and Papas 2003).…”

“…Tocopherols prevent free radical oxidation of lipids and fatty acids in vivo (Bell et al 2000); postslaughter, they can reduce rates of oxidation and lengthen shelf life of fresh or frozen fillets (Gatta et al 2000;Ruff et al 2002;Hamre et al 2004). Tissue a-tocopherol content and oxidative stability have been enhanced via dietary supplementation with SYNE in sunshine bass (Kocabas and Gatlin 1999), rainbow trout Oncorhynchus mykiss (Chaiyapechara et al 2003), European seabass Dicentrarchus labrax (Gatta et al 2000), Atlantic salmon (Hamre et al 1998(Hamre et al , 2004Scaife et al 2000), Atlantic halibut Hippoglossus hippoglossus (Ruff et al 2002(Ruff et al , 2004, and turbot Scophthalmus maximus (Ruff et al 2003(Ruff et al , 2004. Although no significant differences were noted after long-term storage, fillet aldehydes numerically decreased with increasing dietary NSVE but not with ethoxyquin.…”

Desempenho produtivo de tambacus alimentados com dietas suplementadas com vitamina E

“…Huang et al (2004), em estudos realizados com salmões (Oncorhynchus kisutsh), relataram taxas de crescimento semelhantes entre os peixes alimentados com 100 mg kg -1 de vitamina E e o grupo controle. Já Ruff (2002) não observou diferença de crescimento entre os tratamentos com 189 e 613 mg kg -1…”