Antioxidant protection of white grape pomace on restructured fish products during frozen storage

White grape antioxidant dietary fibre (WGDF) was obtained from white grape (Vitis vinifera, var. Airén) pomace from wine production. The antioxidant capacity of WGDF was determined in minced fish muscle (MFM) during frozen storage. Concentrations of 0, 2, and 4% WGDF ((0-WGDF), (2-WGDF), and (4-WGDF) respectively) were added to MFM samples. Analyses were carried out immediately after preparation of samples and over 6 months of storage at −20 °C. WGDF was characterized in terms of dietary fibre (DF) (insoluble and soluble), total polyphenols and antioxidant capacity, and multifunctional antioxidant assays were done on all the MFM samples. The addition of white grape DF considerably delayed lipid oxidation in minced horse mackerel muscle during the frozen storage. Vacuum-packing the sample with 2% WGDF significantly enhanced the antioxidant properties of WGDF.     

Effect of plant extracts on lipid oxidation during frozen storage of minced fish muscle

The aim of the study is to determine the effect of pomegranate seed extract (PSE) and grape seed extract (GSE) addition to chub mackerel minced muscle on lipid oxidation during frozen storage. Each extract was added to minced fish muscle at 2% concentration and then stored at ?18 °C for 3 months. The effect of plant dietary fibres to control lipid oxidation was compared with untreated samples (control). Formation of lipid hydroperoxides and thiobarbituric acid‐reactive substances (TBARS) was significantly inhibited by PSE and GSE addition when compared with control. Both extracts significantly retarded lipid oxidation according to the results of TBARS. A significant reduction of L* (lightness), a* (redness) and b* (yellowness) values was detected during frozen storage. GSE added samples had the highest redness and the lowest lightness and yellowness. However, samples with PSE showed the lowest redness and highest yellowness and h° (hue angle) values. The results from this study suggest GSE is a very effective inhibitor of primary and secondary oxidation products in minced fish muscle and have a potential as a natural antioxidant to control lipid oxidation during frozen storage of fatty fish.     

Effect of grape antioxidant dietary fiber on the lipid oxidation of raw and cooked chicken hamburgers

Efficiency of four concentrations (0.5, 1, 1.5 and 2%) of grape antioxidant dietary fiber (GADF) on susceptibility of raw and cooked chicken breast hamburger to lipid oxidation was investigated after 0, 3, 5 and 13 days of refrigerated storage at 4 °C. Color changes, sensorial qualities and acceptability by panellist were evaluated. Lipid oxidation was assessed by monitoring malondialdehyde formation with 2-thiobarbituric acid (TBARS) assay and radical scavenging capacity by ABTS method. A significant reduction in lightness and yellowness and a significant increase in redness as a result of GADF addition were observed in raw and chicken hamburgers. Addition of GADF significantly improved the oxidative stability and the radical scavenging activity in raw and cooked chicken hamburgers. The ability of GADF to prevent lipid oxidation was concentration-dependent. Acceptability of chicken meat was not affected by the addition of GADF. These results show that GADF is a very effective inhibitor of lipid oxidation and has potential as a natural antioxidant in raw and chicken cooked meats.     

Testing caffeic acid as a natural antioxidant in functional fish-fibre restructured products

The antioxidant effectiveness of caffeic acid addition to minced fish muscle with or without wheat dietary fibre added was studied. Wheat dietary fibre showed a significant prooxidant effect on minced fish muscle during chilled storage that was significantly inhibited in presence of 100 mg/kg caffeic acid. In samples containing caffeic acid and wheat dietary fibre, lipid oxidation was completely inhibited after 10 days. Results obtained from the instrumental texture profile analysis showed that the inclusion of wheat dietary fibre with or without caffeic acid lowered the texture profile analysis parameters. Caffeic acid did not render any changes on the water binding capacity. These results prove that caffeic acid can be successfully used as a natural antioxidant in wheat dietary fibre minced fish restructured products.     

Physical study of minced fish muscle with a white-grape by-product added as an ingredient

ABSTRACT:  Functional properties of a white grape dietary fiber concentrate (WGDF) obtained from wine industry residues were determined with a view to their use as potential functional ingredient in seafood products. The main features of interest of WGDF are that it is a natural product containing high concentrations of dietary fiber (DF) with a high-soluble DF (sDF)/insoluble DF (iDF) ratio and associated bioactive compounds; as such it is considered potentially suitable for use as dietary fiber in the enrichment of foods. WGDF was therefore added to minced fish muscle (MFM) of horse mackerel ( Trachurus trachurus ) to take advantage of its technological properties, and also to enrich a food product that is a functional product in itself but does not contain dietary fiber. WGDF was added (2% and 4%) to MFM, which was stored for 6 mo at –20 °C, and a further lot was vacuum packed. Physical and mechanical properties, sensory and color analyses, microscopy, and electrophoretic profiles were all done in samples every month. The results indicate that WGDF had good functional properties, high water and oil retention capacity, and considerable swelling properties, which would make it useful as a natural ingredient in foods. The addition of WGDF to MFM augmented aggregation of myofibrillar proteins in the course of frozen storage, although electrophoretic profiles were very similar in samples with and without WGDF. The addition of WGDF to MFM made samples softer and less springy and cohesive. SEM showed good dispersion of WGDF in MFM but the matrix was more discontinuous than in the control. Water retention was significantly enhanced when WGDF was added, and the cooking yield improved. In sensory evaluation, samples containing 2% of WGDF scored highest in overall acceptance as compared with the control. Vacuum packing did not significantly affect the properties considered during frozen storage.     

Effect of oregano and rosemary essential oils on lipid oxidation of stored frozen minced gilthead sea bream muscle

The study aimed to determine the effect of oregano and rosemary essential oils addition to minced gilthead sea bream muscle on lipid oxidation during frozen storage. Each essential oil was added to minced fish muscle at 500 mg/kg concentration which then was stored at ?22 °C for 12 months. Oregano essential oils inhibited the formation of conjugated diene and triene hydroperoxides and thiobarbituric reactive substances when compared with untreated samples after the first month and rosemary essential oils after the first and third month of frozen storage. Oregano and rosemary essential oils could be used as ingredients to prevent oxidation in stored frozen minced gilthead sea bream muscle, when long term preservation is not needed. The rate of lipid oxidation depends on antioxidant source. The rosemary essential oil proved to be more efficient in preventing lipid oxidation of minced gilthead sea bream muscle than oregano essential oil.     

Antioxidative effect of dietary grape pomace concentrate on lipid oxidation of chilled and long-term frozen stored chicken patties

Grape pomace concentrate (GPC) is a natural source of phenolic compounds with high antioxidant capacity. The effect of a diet containing GPC on lipid peroxidation levels (TBARS) and antioxidant capacity (ABTS method) of raw and cooked chicken breast meat patties stored in chilled conditions (4 °C) for 0, 3, 6, 13 and 20 days, and long-term frozen storage (6 months) was investigated. Chickens were fed GPC at levels of 0, 30 and 60 mg/kg from 3 to 6 weeks of age. Dietary GPC did not affect chicken performance. Lipid oxidation (TBARS value) was significantly increased by the storage time (0–20 days and 6 months of storage, respectively) in raw and cooked samples. Dietary GPC significantly caused an inhibitory effect on lipid oxidation of raw and cooked breast chicken patties compared with samples obtained from birds fed the control diet at 20 days and long-term frozen storage (6 months). Radical scavenging capacity was significantly increased at 20 days in cooked samples and significantly reduced at 6 months of storage in raw and cooked samples. The higher concentration of dietary GPC increased the ABTS values only in the raw samples. These results indicated that dietary grape pomace concentrate could be effective in inhibiting lipid oxidation of chilled and long-term frozen stored chicken patties.     

Preservation of the endogenous antioxidant system of fish muscle by grape polyphenols during frozen storage

The capacity of a phenolic extract, OW, obtained from grape (Vitis vinifera) by-products, and of a purified fraction of procyanidins from OW, fraction IV, for preservation of endogenous antioxidants of fatty fish was investigated during frozen storage. They were used in muscle concentrations of 0.01% (w/w). Grape polyphenols were compared with propyl gallate, a synthetic antioxidant. The exogenous compounds were added to minced mackerel (Scomber scombrus) muscle and horse mackerel (Trauchurus trauchurus) fillets, before freezing at –10 °C. The results demonstrated that grape polyphenols and propyl gallate inhibit the depletion of endogenous -tocopherol, ubiquinone-10 and total glutathione. Grape polyphenols and propyl gallate showed similar efficiency for preservation of ubiquinone, in both minced and filleted muscle, and total glutathione, in minced muscle. Total glutathione in the fillets was better maintained by propyl gallate than grape polyphenols. The endogenous antioxidant more efficiently preserved by grape polyphenols and propyl gallate was -tocopherol. Its loss elapsed faster in the order control> OW>fraction IV>propyl gallate. The depletion of -tocopherol was highly correlated with the evolution of lipid oxidation. The development of lipid oxidation was repressed, while the concentration of -tocopherol was not reduced up to critical levels.     

Quality loss during the frozen storage of sea salmon (Pseudopercis semifasciata). Effect of rosemary (Rosmarinus officinalis L.) extract

Lipid and protein alterations during the frozen storage (−11 °C) were analyzed in minced sea salmon muscles to evaluate the effect of the application of rosemary extract (200 and 500 mg/kg). Lipid oxidation reached maximum TBA values between 3 and 4 months of storage in untreated muscles. The main polyunsaturated fatty acids affected were 22:6-ω3, 22:5-ω3 and 20:4-ω6 acids. Phospholipid hydrolysis was also detected. Rosemary extract reduced lipid oxidation for 6 months (500 mg/kg, muscle with 10.8 g/kg lipids) or 3 months (200 mg/kg, muscle with 5.3 g/kg lipids). Myofibrillar proteins showed a decrease of extractability (80%) after 2 months of storage. Myosin denaturation was evident by DSC at 3 months, while myosin and actin peaks disappeared at 6 months. A diminution of extractable polypeptides of high molecular weight was recorded by SDS-PAGE after 3 months. The available lysine content suffered a reduction starting at 3 months of storage, suggesting some interaction involving the free amino groups of lysine. Fluorescent compounds' determination did not show changes due to the interaction of lipid oxidation products and proteins, while protein alterations could not be reduced by the rosemary extract. Furthermore, the antioxidant reduced the loss of red color in the muscle.     

Influence of the in vivo addition of alpha-tocopheryl acetate with three lipid sources on the lipid oxidation and fatty acid composition of Beluga sturgeon, Huso huso, during frozen storage

This study was conducted to investigate the effect of dietary alpha-tocopheryl acetate (vitamin E) and oil sources on fish flesh quality characteristics of Huso huso during frozen storage. Practical-type diets containing 0 or 250 mg vitamin E kg⁻¹ with three lipid sources, fish oil (FO), soybean oil (SO) and canola oil (CO), were fed to H. huso for 120 days. Fillet samples were analysed fresh or after storage at −18 ± 1 °C for 12 months. Replacement of FO by SO and CO in diets for H. huso significantly altered the fatty acid (FA) profile, which also influenced the FA composition during frozen storage. Dietary vitamin E had a significant effect on muscle vitamin E content and lipid oxidation during storage (P > 0.05). Oxidation was reduced for fish fed vitamin E and results showed that dietary vitamin E supplementation can slow down the level of lipid oxidation in H. huso muscles during frozen storage.     

Inhibition of lipid oxidation in refrigerated and frozen salted raw minced chicken breasts with electron beam irradiated almond skin powder

Antioxidant effects of electron beam irradiated almond skin powder (ASP) in raw minced chicken breasts (MCB) during refrigerated and frozen storage were studied. MCB samples were treated with BHT, non-irradiated ASP (0 kGy), irradiated ASP (10 kGy, 20 kGy and 30 kGy) and compared to MCB without antioxidants. Colour was determined on initial and final day of analysis while conjugated dienes (CD), peroxide values (POV), TBARS and hexanal content were evaluated periodically for 12 days of refrigerated storage and seven months of frozen storage. ASP addition lowered L* values compared to MCB without ASP or BHT. During refrigerated storage, MCB containing ASP had decreased formation of lipid oxidation products ranging from 0 to 66%, 7 to 24%, 0 to 37% and 4 to 71% reduction in POV, CD, TBARS and hexanal content, respectively, as compared to MCB without antioxidants over duration of study. A 15–65%, 3–25%, 14–50% and 28–82% reduction in POV, CD, TBARS and hexanal content, respectively, for frozen MCB was detected.     

Antioxidant Effects of Grape Pomace on the Quality of Silver Carp (Hypophthalmichthys molitrix) Fillets During Refrigerated Storage

This study aimed to determine the phenolic content and antioxidant effect of grape pomace extract on silver carp fillets during refrigerated storage. Total phenolic content of grape pomace extract was quantified by colorimetric methods. Silver carp samples were treated with 0, 2, and 4% of grape pomace extract (g extract/100 g flesh) and stored 15 days in a refrigerator (4°C). Changes in pH, peroxide value, thiobarbituric acid, and heme iron at 0, 3, 6, 9, 12, and 15 days of storage were investigated. Results showed that the values of pH, peroxide value, and thiobarbituric acid increased and iron levels decreased in all treatments during storage (p < 0.05). The phenolic contents were generally much more influenced by the quality parameters treated compared to the control. The addition of grape pomace extract delayed lipid oxidation in silver carp fillet considerably during refrigerated storage. These results suggested that grape pomace extract has the potential to be used as a natural antioxidant.     

Inhibition of lipid oxidation in refrigerated and frozen salted raw minced chicken breasts with electron beam irradiated almond skin powder

Antioxidant effects of electron beam irradiated almond skin powder (ASP) in raw minced chicken breasts (MCB) during refrigerated and frozen storage were studied. MCB samples were treated with BHT, non-irradiated ASP (0 kGy), irradiated ASP (10 kGy, 20 kGy and 30 kGy) and compared to MCB without antioxidants. Colour was determined on initial and final day of analysis while conjugated dienes (CD), peroxide values (POV), TBARS and hexanal content were evaluated periodically for 12 days of refrigerated storage and seven months of frozen storage. ASP addition lowered L* values compared to MCB without ASP or BHT. During refrigerated storage, MCB containing ASP had decreased formation of lipid oxidation products ranging from 0 to 66%, 7 to 24%, 0 to 37% and 4 to 71% reduction in POV, CD, TBARS and hexanal content, respectively, as compared to MCB without antioxidants over duration of study. A 15–65%, 3–25%, 14–50% and 28–82% reduction in POV, CD, TBARS and hexanal content, respectively, for frozen MCB was detected.     

Effects of calf diet, antioxidants, packaging type and storage time on beef steak storage

The effect of basal dietary supplemented with vegetable oils plus vitamin E (sunflower, soybean, linseed and a basal diet control), type of packaging (MAP or vacuum), addition of natural antioxidant (grape seed, rosemary) and storage time (0, 7, 14 and 21 days) on lipid oxidation, color stability, vitamin E content, and total aerobic bacterial counts in steaks of Longissimus thoracis was studied. The triple interaction diet × time × packaging affected oxidative stability, redness and yellowness of the meat. TBARS values did not increase with time in vacuum-packaged samples for all dietary treatments. However, samples from MAP and control showed the highest TBARS values after 21 days of storage (0.72 mg MDA/kg of meat, P < 0.05). Both exogenous antioxidant extracts and MAP maintained low total aerobic counts in steaks until the 21st day. Calves should be fed a diet supplemented with L-VE, stored in MAP and treated with grape seed extract to extend the shelf life of their meat.     

Effectiveness of a natural Rosemary (Rosmarinus officinalis) extract on the stability of filleted and minced fish during frozen storage

 The objective of this study was to evaluate the effect of adding a natural Rosemary (Rosmarinus officinalis L.) extract to filleted and minced frozen fish and to compare the fat stability of the samples with that of the controls. Horse mackerel (Trachurus trachurus), a relatively fatty fish, and Mediterranean hake (Merluccius mediterraneus), a low-fat fish, were used. Fat stability evaluation was done by comparing the changes of the malondialdehyde (MDA) content and the percentage of polyunsaturated fatty acid (PUFAs) degradation that occurred during frozen storage at –18°C for 120 days. Total volatile bases-N (TVB-N) were also measured to assess for quality. The results showed that the natural antioxidant extract retarded the oxidation process throughout storage. The control samples of both filleted and minced frozen fish of both species showed a significant reduction (^* P <0.05) of PUFAs until day 50 of storage, while the oxidation was gradual but slower in the treated samples. Fillets and minced samples of both species treated with antioxidant contained significantly (^* P <0.05) less MDA compared with the controls during storage. Received: 2 December 1996     

Effectiveness of a natural Rosemary (Rosmarinus officinalis) extract on the stability of filleted and minced fish during frozen storage

 The objective of this study was to evaluate the effect of adding a natural Rosemary (Rosmarinus officinalis L.) extract to filleted and minced frozen fish and to compare the fat stability of the samples with that of the controls. Horse mackerel (Trachurus trachurus), a relatively fatty fish, and Mediterranean hake (Merluccius mediterraneus), a low-fat fish, were used. Fat stability evaluation was done by comparing the changes of the malondialdehyde (MDA) content and the percentage of polyunsaturated fatty acid (PUFAs) degradation that occurred during frozen storage at –18°C for 120 days. Total volatile bases-N (TVB-N) were also measured to assess for quality. The results showed that the natural antioxidant extract retarded the oxidation process throughout storage. The control samples of both filleted and minced frozen fish of both species showed a significant reduction (^* P <0.05) of PUFAs until day 50 of storage, while the oxidation was gradual but slower in the treated samples. Fillets and minced samples of both species treated with antioxidant contained significantly (^* P <0.05) less MDA compared with the controls during storage. Received: 2 December 1996     

Frozen storage of minced prawn flesh: effect of sorbitol, egg white and starch as protective ingredients

 The functionality of minced prawn flesh during frozen storage, with and without added ingredients as protectants, was examined in terms of water-holding capacity, protein solubility, viscosity, texture and gel-forming capacity. Different lots containing sorbitol, egg white and starch were studied. Minced prawn showed high protein solubility which remained constant after 3 months of frozen storage, regardless of the ingredients used. A slight increase in shear strength during the storage period was suppressed by the addition of ingredients; however, these were not effective at substantially improving the gel-forming capacity of the minced prawn. Viscosity was the property most affected by frozen storage, and was improved by the addition of ingredients.     

EFFECT OF DIETARY COMPONENTS AND SURFACE APPLICATION OF OLEORESIN ROSEMARY ON LIPID STABILITY OF RAINBOW TROUT (Oncorhynchus mykiss) MUSCLE DURING REFRIGERATED AND FROZEN STORAGE

The effect of dietary supplementation with α-tocopherol and surface application of oleoresin rosemary on the lipid stability of rainbow trout ( Oncorhynchus mykiss ) muscle during refrigerated storage (4C) and frozen storage (−20C) for 8 days and 6 months, respectively, was investigated. A significant (p < 0.05) reduction in α-tocopherol concentrations in muscle tissue during frozen storage was observed. The 2-thiobarbituric acid-reactive substances (TBARS) values of muscle samples, with or without surface application of oleoresin rosemary, increased during storage for all dietary groups. A significant (P < 0.05) interaction between dietary treatments and the time of storage was observed. Muscle tissue from fish receiving a dietary supplement of 500 mg/kg diet had the lowest TBARS values. The oxidative stability of the lipids was further improved by applying oleoresin rosemary to the surface of the fish fillets.     

Addition of tea catechins and vitamin C on sensory evaluation, colour and lipid stability during chilled storage in cooked or raw beef and chicken patties

The effects of addition of tea catechins (TC) and vitamin C (VC) on sensory evaluation, colour and lipid stability in cooked or raw beef and chicken meat patties during refrigerated storage were studied. Fresh beef striploin and chicken breast muscles were minced, following removal of external fat and connective tissue. Following mincing, beef and chicken were assigned to one of the following five treatments: control (meat treated with no antioxidant); TC200, meat plus 200 mg TC/kg muscle; TC400, meat plus 400 mg TC/kg muscle; VC200, meat plus 200 mg VC/kg muscle, VC400, meat plus 400 mg VC/kg muscle. Sodium chloride (1%) was added to all samples. Patties (125 g portions), formed from the above-treated minced meat, were oven cooked, cooled, and packaged in 30% CO₂:70% N₂. Fresh raw beef and chicken patties were packaged in 80% O₂:20% CO₂. All samples were stored for up to 7 days under fluorescent lighting at 4 °C. Sensory parameters (colour, flavour, taste, tenderness and overall acceptability) were evaluated on cooked beef and chicken patties after 1, 3 and 6 days of storage. Surface colour (Hunter L, a and b values), and lipid oxidation (2-thiobarbituric acid reactive substances) were measured on days 1, 3 and 6 of storage for cooked meats and on days 2 and 7 for raw beef and chicken. Tea catechins addition (200 or 400 mg/kg) to minced meat caused (P < 0.05) discolouration in cooked beef and chicken meat patties and significantly reduced (P < 0.001) lipid oxidation in cooked or raw beef patties compared to the control. Beef, either raw or cooked, was more susceptible (P < 0.01) to oxidation compared to chicken. Raw meat stored in high oxygen conditions was more susceptible to lipid oxidation than cooked meat stored in anaerobic conditions. Tea catechins treatments (TC200 and TC400) inhibited (P < 0.05) lipid oxidation in raw beef to a greater extent than vitamin C treatments (VC200 and VC400). These results indicate that tea catechins are potent natural antioxidants and exhibit greater antioxidant efficacy compared to vitamin C.     

Inhibition of lipid oxidation in long-term frozen stored chicken meat by dietary oregano essential oil and α-tocopheryl acetate supplementation

The antioxidative effect of dietary oregano essential oil and α-tocopheryl acetate supplementation on susceptibility of chicken breast and thigh muscle meat to lipid oxidation during frozen storage at −20 °C for 9 months was examined. Day-old chickens (n=80) were randomly divided into four groups, and fed a basal diet containing 30 mg α-tocopheryl acetate kg⁻¹ feed as control, or basal diet plus 200 mg α-tocopheryl acetate kg⁻¹ feed, or basal diet plus 50 or 100 mg oregano essential oil kg⁻¹ for 38 days prior to slaughter. Lipid oxidation was assessed by monitoring malondialdehyde (MDA) formation with third-order derivative spectrophotometry, after zero and 7 days of refrigerated storage at 4 °C following 1, 3, 6 and 9 months of frozen storage. Results clearly demonstrated that all dietary treatments had a major impact on the oxidative stability of broiler meat. Dietary oregano essential oil supplementation at the level of 100 mg kg¹ feed was significantly (P⩽0.05) more effective in reducing lipid oxidation compared with the level of 50 mg oregano essential oil kg⁻¹ feed and control, but less effective (P⩽0.05) compared with α-tocopheryl acetate supplementation. Thigh muscle was found to be more susceptible to oxidation compared to breast muscle, although the former contained α-tocopherol at markedly higher levels. Mean α-tocopherol levels in muscle samples decreased during the frozen storage, the decrease being sharper between 1–3 months and 3–6 months of frozen storage for breast and thigh muscle samples, respectively.