THE EFFECTS OF DIETARY α-TOCOPHEROL AND SURFACE APPLICATION OF OLEORESIN ROSEMARY ON LIPID OXIDATION AND CHOLESTEROL OXIDE FORMATION IN COOKED RAINBOW TROUT (Oncorhynchus mykiss) MUSCLE

The inhibitory effect of dietary α-tocopherol supplementation (100 and 500 mg α-tocopheryl acetate/kg diet) and an oleoresin rosemary dip on lipid and cholesterol oxidation in cooked rainbow trout ( Oncorhynchus mykiss ) during storage at 4C for 48 h was investigated. The 2-thiobarbituric acid-reactive substances (TBARS) values of cooked fish muscle increased during storage for all treatments. Dietary α-tocopherol supplementation partially inhibited lipid oxidation. Surface application of oleoresin rosemary further enhanced this protective effect. Cholesterol oxides were formed in all the samples following cooking and storage. The major cholesterol oxidation products (COPS) were identified as 7 β-hydroxycholesterol, α- and β-epoxides, and 7-ketocholesterol. Formation of COPS was reduced by dietary supplementation with α-tocopherol and surface application of oleoresin rosemary. Statistical analysis revealed a highly significant (p < 0.01) inhibitory effect of oleoresin rosemary on COPS formation.     

Effect of dietary α-tocopherol supplementation and gamma-irradiation on α-tocopherol retention and lipid oxidation in cooked minced chicken

The effects of dietary α-tocopherol supplementation and gamma-irradiation on α-tocopherol retention and lipid oxidation in cooked minced chicken during refrigerated storage were studied. Minced breast and thigh meat from broilers fed diets supplemented with 100, 200 or 400 mg α-tocopheryl acetate/kg feed was irradiated at 2.5 or 4.0kGy. Cooked irradiated and unirradiated meat was stored at 4 °C for 5 days. α-Tocopherol concentrations increased with increasing dietary supplementation. Concentrations decreased during storage, but retention was not affected by irradiation. Lipid stability was determined by measuring the formation of thiobarbituric acid-reacting substances (TBARS) and cholesterol oxidation products (COPs) during storage. TBARS and COPs increased during storage and were reduced by increasing levels of dietary α-tocopheryl acetate supplementation. Irradiation accelerated TBARS formation during storage, but this was prevented by supplementation with 200 mg α-tocopheryl acetate/kg feed. Irradiation tended to increase COPs during storage, although no consistent effects were observed. In general supplementation with over 400 mg α-tocopheryl acetate/kg feed may be required to control cholesterol oxidation in minced chicken. The results suggest that, overall, irradiation had little effect on lipid stability in α-tocopherol-supplemented meat following cooking and storage.     

Separation and Identification of Cholesterol Oxidation Products in Dried Egg Preparations

A technique is described for the simultaneous determination of a wide range of angiotoxic sterols in foods produced by the oxidation of cholesterol. Gas chromatography using on-column injection onto a bonded phase fused silica capillary column gave excellent separation of the oxides examined. Combined gas chromatography- mass spectrometry was used to confirm the identities of the trimethylsilyl ether derivatives of the various sterols and 6-ketocholestanol was found to be an acceptable internal standard for determination. Analysis of powdered scrambled egg mix showed the presence of several cholesterol oxides, with cholesterol-5α,6α-epoxide, cholesterol-5β,6β-epoxide and 7-ketocholesterol predominating. Other atherogenic sterols identified included 25-hydroxycholesterol, 7α-hydroxycholesterol, 7β-hydroxycholesterol and 5α-cholestane-3β,5,6β-triol.     

Effect of carnosine, salt and dietary vitamin E on the oxidative stability of chicken meat

The effect of carnosine on lipid and cholesterol oxidation in salted chicken thigh meat and its relationship to dietary α-tocopherol supplementation was examined. Broilers (Cobb 500) were fed diets with a basal (30 mg kg(-1)) or supplemental (200 mg kg(-1)) level of α-tocopheryl acetate for 6 weeks. Thigh meat patties were prepared with carnosine (1.5%), salt (1%) or salt plus carnosine. Salt accelerated lipid and cholesterol oxidation following cooking and refrigerated storage. However, carnosine inhibited lipid and cholesterol oxidation in salted patties. Dietary α-tocopherol supplementation also reduced the extent of lipid and cholesterol oxidation in salted patties. The combination of carnosine and dietary α-tocopherol resulted in the greatest lipid and cholesterol stability in salted meat.     

Cholesterol oxidation in frozen dark chicken meat: influence of dietary fat source, and α-tocopherol and ascorbic acid supplementation

A factorial design assessed the effect of dietary fat source (beef tallow, fresh and oxidized sunflower oils, and linseed oil), and α-tocopheryl acetate (α-TA) and ascorbic acid (AA) supplementation (225 and 110 mg/kg feed, respectively) on the cholesterol oxidation product (COP) content and 2-thiobarbituric acid (TBA) values in raw and cooked dark chicken meat vacuum packaged and stored at -20°C for 7 months. COP determination showed good linearity, recovery and precision. Dietary α-TA was highly effective in protecting raw or cooked meat from cholesterol and fatty acid oxidation, regardless of its degree of unsaturation. In contrast, AA supplementation was ineffective and even promoted oxidation in raw meat from broilers fed unsaturated fat diets that had not been supplemented with α-TA. Oxidation values (raw or cooked meat) from α-TA or α-TA+AA supplemented diets were not statistically different (P>0.05). TBA and COP values were significantly correlated in raw samples (r=0.6466, P=0.0001).     

Effects of differential supplementation of fatty acids during the peripartum and breeding periods of Holstein cows: II. Neutrophil fatty acids and function, and acute phase proteins

The objectives were to evaluate the effects of differential supplementation of Ca salts (CS) of fatty acids (FA) on plasma acute phase proteins and both FA composition and function (i.e., activity and cytokine production) of neutrophils, during the peripartum and breeding periods. Holstein cows were assigned randomly to receive either CS of palm (PO) or safflower (SO) oils from 30 d prepartum until 35 d postpartum (dpp) and CS of PO or fish oil (FO) from 35 to 160 dpp. Supplementation of CS of FA was at 1.5% of dietary dry matter. Cows (n = 32) were sampled three times weekly from parturition to 35 dpp for analyses of plasma concentrations of haptoglobin and fibrinogen. Cows (n = 47) were sampled for neutrophil phagocytic and oxidative burst activities toward Escherichia coli and Staphylococcus aureus, and neutrophil abundances of L-selectin and β₂-integrin assessed by flow cytometry at 32 d prepartum, within 7 h after parturition, and 4 and 7 dpp. Profiles of FA in neutrophils and cytokine production (i.e., tumor necrosis factor alpha, TNF-α, and IL-1β) were assessed prepartum (n = 14), 35 (PO vs. SO; n = 26) and 85 dpp (PO vs. FO; n = 28). Plasma concentrations of haptoglobin and fibrinogen were greater for cows fed SO compared with PO. The percentage of neutrophils with phagocytic and oxidative burst activities was not affected by transition diets, but activities per neutrophil were greater in SO compared with PO diets at 4 (phagocytosis and oxidative burst) and 7 dpp (oxidative burst). Neutrophil abundance of L-selectin, but not β₂-integrin, was greater in SO compared with PO at 4 and 7 dpp. Neutrophil productions of TNF-α and IL-1β were increased at 35 dpp in SO compared with PO diets, but production of TNF-α was attenuated in FO compared with PO at 85 dpp. Neutrophil ratios of n-6:n-3 FA were greater at 35 dpp in the SO diet and less at 85 dpp in FO compared with PO diets. In conclusion, cows supplemented with CS of SO had improved innate immunity (i.e., acute phase response and neutrophil function) to better cope with the bacterial challenges in the postpartum period. Conversely, CS of FO attenuated neutrophil cytokine production.     

Effect of natural antioxidant combinations on lipid oxidation in cooked chicken meat during refrigerated storage

The effect of combinations of sage, oregano and honey on lipid oxidation in cooked chicken meat during refrigeration at 4°C for 96h was determined. Chicken samples (thigh and breast) were then separated into five groups: control; butylated hydroxytoluene; oregano+sage; oregano+sage+5%honey and oregano+sage+10%honey. Quantitative measurements of thiobarbituric acid reactive substances, conjugated dienes, hexanal, fatty acids, cholesterol and cholesterol oxides were used as indicators of lipid oxidation. Acceptability and preference were also evaluated. The effectiveness of the natural antioxidants for reducing the velocity of lipid oxidation in cooked chicken thigh and breast was demonstrated after 48 and 96h of refrigeration at 4°C. The treatments that presented the lowest hexanal values after 96h of refrigeration were oregano+sage+5%honey and oregano+sage+10%honey. Only traces of free cholesterol oxides were found (25-OH, 7-k, 7α-OH and 7β-OH). The natural antioxidants protected cooked chicken meat from oxidation processes and resulted in great acceptability.     

Antioxidative effect of dietary tea catechins on lipid oxidation of long-term frozen stored chicken meat

The antioxidative effect of dietary tea catechins (TC) supplementation at levels of 50, 100, 200 and 300 mg kg(-1) feed on susceptibility of chicken breast and thigh meat to lipid oxidation during frozen (-20°C) storage for 9 months was investigated. Day-old chickens (Cobb 500, n=200) were randomly divided into six groups. Chickens were fed a basal diet containing 20 mg α-tocopheryl acetate kg(-1) feed as control, or a vitamin E supplemented diet (basal diet plus 200 mg α-tocopheryl acetate kg(-1) feed), or TC supplemented diets (basal diet plus 50, 100, 200 or 300 mg TC kg(-1) feed) for 6 weeks prior to slaughter. Lipid oxidation (TBARS) was assessed after 0 and 10 days of refrigerated display (4°C) following 1, 3, 6, and 9 months of frozen (-20°C) storage. TC supplementation at all concentrations showed antioxidative effects for both breast and thigh chicken meat during the 9 months of frozen storage compared to the control sample. TC supplementation at levels of 200 and 300 mg kg(-1) feed were more effective (P<0.05) in delaying lipid oxidation in all meat samples compared to the control. TC supplementation at a level of 200 mg kg(-1) feed showed antioxidant activity equivalent to α-tocopheryl acetate fed at the same level up to 3 months of frozen storage. For long-term frozen storage up to 9 months, however, TC supplementation at 300 mg kg(-1) feed was required as a replacement for α-tocopheryl acetate at a level of 200 mg kg(-1) feed. The results obtained showed a long-term antioxidative effect exhibited by dietary tea catechins on chicken meat during frozen storage and demonstrated that tea catechins are effective alternatives to vitamin E as natural dietary antioxidants.     

Influence of Dietary Supplementation with α-Tocopheryl Acetate and Canthaxanthin on Cholesterol Oxidation in ω3 and ω6 Fatty Acid-enriched Spray-dried Eggs

ABSTRACT: The effect of feeding laying hens linseed oil or sunflower oil, with and without α-tocopheryl acetate and/or canthaxanthin, was evaluated on cholesterol oxidation in spray-dried whole egg at various storage periods. Storage of spray-dried eggs at room temperature in the dark resulted in an increase in cholesterol oxidation products from 18.1 μg/g, after spray drying, to 39.3 μg/g, at 12 mo of storage. No differences were found with either dietary oil or canthaxanthin supplementation. However, α-tocopheryl acetate supplementation resulted in a lower formation of cholesterol oxidation products during storage. No synergistic effect between α-tocopherol and canthaxanthin was detected.     

Lipid and cholesterol oxidation in chicken meat are inhibited by sage but not by garlic

The effects of the addition of sage and garlic in chicken meat on lipid and cholesterol oxidation, having as prooxidant factors the addition of salt, thermal treatment, and frozen storage, were evaluated. The content of unsaturated fatty acids did not change in the presence of sage; on the contrary, with garlic, the content of these fatty acids decreased after cooking and storage. Hexanal and pentanal contents were lower in patties containing sage, and higher in those with garlic. The 7-ketocholesterol was the cholesterol oxide found in higher amount in raw chicken on day 0, while the formation of 7β- and 7α-hydroxycholesterol was verified only from day 30 on. Cooking and storage resulted in increase of total cholesterol oxides and decrease of α- and γ-tocopherol. Sage was effective in controlling lipid and cholesterol oxidation, minimizing the prooxidant effects of salt, cooking, and storage. However, garlic presented no effect as antioxidant and accelerated lipid oxidation. PRACTICAL APPLICATION: The addition of sage to chicken meat (0.1 g/100 g) is a good alternative to prevent and delay the formation of compounds derived from lipid oxidation that are responsible for off-flavors and loss of nutritional quality during long-term frozen storage. Care must be taken when using garlic to seasoning chicken meat products, such as hamburgers and meatballs, especially cooked or precooked due to its potential to promote lipid oxidation and consequently raising the risk of having the product rejected by the consumer.     

气质联用法测定反复冻融畜禽肉中胆固醇及其氧化物含量

本文以畜禽肉中胆固醇及胆固醇氧化物、水分、丙二醛指标变化,考察了反复冻融对畜禽肉品质的影响。采用气相色谱-串联质谱/质谱(GC-MS/MS)测定方法,对反复冻融7次(新鲜肉记为冻融0次)后鸡肉、猪肉和牛肉中胆固醇及5种胆固醇氧化物(25-羟基胆固醇、7β-羟基胆固醇、20α-羟基胆固醇、5α,6α-环氧化胆固醇、7-酮基胆固醇)的含量进行了测定。结果表明,随着冻融次数的增加,胆固醇含量逐渐降低,其中牛肉中的胆固醇含量减少尤为明显(减少量为32.47 μg/g)。在反复冻融的过程中,胆固醇氧化物的含量先逐渐增加,后趋于平稳,其中鸡腿肉中7β-羟基胆固醇含量增加最多(增加量为0.601 μg/g)。同时,通过对畜禽肉中脂质过氧化过程中的水分含量和丙二醛含量进行考察,鸡胸肉中的水分减少最多(减少量为14.472 g/100 g),牛肉中的丙二醛增加量最多(增量为1.004 μg/g)。反复冻融会导致畜禽肉胆固醇氧化增加,品质下降。     

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.     

Phytosterol oxides content in selected thermally processed products

Heat treatments are very popular methods of food preparation in European countries. Phytosterol present in foodstuffs undergoes oxidative changes during heat treatment, and phytosterol oxides (e.g., 7α-, 7β-hydroxysterol, 5α,6α-, 5β,6β-epoxysterol, 7-ketosterol and triol) are formed. Phytosterol oxidation products (POPs) have been associated with cytotoxic and pro-apoptotic effects in humans. On the other hand, several studies conducted on animals revealed that some phytosterol oxides lower serum triacyglycerol and blood glucose levels. The aim of this study was to evaluate the effect of heat treatment on formation of phytosterol oxidation products in selected foodstuffs. The following products were taken into considerations: minced meat (pork and beef), frozen French fries, frozen fish fillets, frozen fish products (e.g., fish sticks), wheat and egg noodles. Sterols and POPs content was evaluated by GC–MS working in total and selected ion monitoring modes. The phytosterol oxidation rate was higher in French fries and fish fillets (0.20–1.69% of total phytosterol content) than in noodles, minced meats and readymade fish products (in 0.04–0.36% range). Method of POPs determination using GC–MS is reported in this study. Results of this study show also that products of the animal origin might be considered as sources of the phytosterol oxides in the human diet.     

Lipid and protein oxidation of chicken breast rolls as affected by dietary oxidation levels and packaging

The objective of this study was to determine the effects of dietary treatment and packaging on the oxidative stability of breast rolls. A total of 120 4-wk-old broiler chickens were randomly assigned to control, oxidized diet (5% oxidized oil, PV = 100), or antioxidants-added diet (500 IU vitamin E + 200 ppm BHA) and fed for 2 wk. Breast muscles were separated from the carcasses and breast rolls were prepared. The rolls were cooked in a smoke house (85 °C) to an internal temperature of 74 °C, cooled, sliced to 2-cm thick pieces, individually packaged in oxygen permeable bags or vacuum-packaged in oxygen impermeable bags, and stored in a 4 °C cold room for 7 d. Lipid, protein oxidation and volatiles were determined at 1, 4, and 7 d of storage. Dietary supplementation of antioxidants significantly reduced lipid oxidation (TBARS) and protein oxidation (carbonyls) in breast rolls, and the effect of dietary antioxidants on lipid oxidation was more pronounced than protein oxidation. Chicken breast rolls from antioxidants treatment group produced significantly lower amounts of hexanal and pentanal than those from control and oxidized oil treatments (P < 0.05). However, dietary oxidized oil did not increase lipid and protein oxidation in breast rolls. Vacuum-packaging significantly delayed the onset of lipid oxidation and protein oxidation in chicken rolls during 7-day refrigerated storage (P < 0.05). Therefore, it is suggested that appropriate use of dietary supplementation of antioxidants in combination with packaging could minimize lipid oxidation in chicken breast rolls.     

Effect of processing technology on the quality and composition of lipids of precooked chicken patties

The effect of processing technology on the quality and composition of lipids of raw meat and precooked ready-to-eat fried chicken patties was studied. Chicken cutlets were obtained by two processing technologies, which mainly differed by the order of the applied thermal treatments (flash-frying and humid steam-convection oven cooking). In the traditional technology, samples were flash-fried and then subjected to oven-cooking, whereas these two processing phases were inverted for the innovative one. Lipid hydrolysis (total fatty acids, free fatty acids, diacylglycerols, free cholesterol) and oxidation [peroxide value (POV) and cholesterol oxidation products (COP)] were evaluated in the raw meat, prefinal and final products. Lipid hydrolysis was significantly more intense in the final products obtained by the innovative technology, whereas no significant differences were found in the oxidation parameters between the products obtained by the two processing lines.     

Inhibition of Lipid Oxidation in Chicken by Carnosine and Dietary α-Tocopherol Supplementation and its Determination by Derivative Spectrophotometry

The antioxidant activity of carnosine in chicken meat, and its relationship to dietary α-tocopherol supplementation, was examined. Broiler chickens were fed diets containing 30 (basal) or 200 (supplemental) mg α-tocopherol acetate kg⁻¹ feed for 6 weeks. Raw and cooked thigh meat patties containing carnosine (0–1·5%) were prepared. Lipid oxidation, during refrigerated storage under fluorescent light, was assessed by monitoring malonaldehyde formation, using the TBA assay and single wavelength (conventional) or first derivative spectrophotometry. In raw patties, added carnosine improved oxidative stability for up to 10 days of refrigerated storage. In cooked patties, the 1·5% carnosine level provided the best antioxidant protection during 7 days of storage. Carnosine (1·5%) was at least as effective as supplemental α-tocopherol in improving the oxidative stability of raw and cooked patties. The presence of both antioxidants had an additive effect on oxidative stability. Overall, the use of derivative spectrophotometry improved the specificity of the TBA assay for monitoring MDA formation in refrigerated meats.     

Effect of dietary vitamin E, fishmeal and wood and liquid smoke on the oxidative stability of bacon during 16 weeks' frozen storage

Twelve (Large White×Landrace) gilts were randomly allotted in a 2×2 factorial design with the respective factor being dietary vitamin E (10 or 200 mg/kg feed) and dietary fishmeal (0 or 5%). Bacon was manufactured from the meat obtained from the animals after slaughter using wood smoke only or a combination of liquid and wood smoke. The oxidative stability of the bacon was examined over 16 weeks of frozen storage. Lipid oxidation in the product was measured by means of thiobarbituric acid reactive substances (TBARS) and fluorescence shift. Dietary fishmeal supplementation increased lipid oxidation in bacon, while dietary vitamin E supplementation reduced lipid oxidation in the product. Lipid oxidation in frozen bacon was successfully reduced when bacon was manufactured from pigs fed a diet supplemented with or without 200 mg of α-tocopherol per kilogram of feed and processed with a combination of liquid and wood smoke. It is concluded that bacon processed with a combination of liquid and wood smoke was significantly less (P<0.001) susceptible to lipid oxidation than bacon processed with wood smoke only.     

Effect of dietary supplementation of vitamin E on characteristics of lamb meat packed under modified atmosphere

The effect of dietary vitamin E supplementation on modified-atmosphere packed lamb meat during storage was studied. Thirty-six weaned male Manchego breed lambs were fed diets supplemented with three different vitamin E concentrations (0, 250, 500 and 1000 mg/kg feed) for an average of 37 days, in the 13–26 kg live weight growth range. Slices of m. longissimus dorsi were packaged under modified atmosphere (70% O₂ and 30% CO₂), stored at 2 ± 1 °C in darkness for 14 and 28 days. Meat quality parameters after both storage periods were assessed. Dietary vitamin E supplementation significantly increased -tocopherol concentration in muscle. Initially, lipid oxidation (TBARS), meat colour and bacterial load were similar in all groups. Lipid and colour oxidation of meat increased significantly (P < 0.001) throughout storage. The increase was greater in non-supplemented lambs than in supplemented ones. The bacterial counts after 28 days of storage reached the limit for microbiological shelf life (7 log₁₀cfu/cm²). Dietary vitamin E supplementation increased the shelf life of meat packaged under modified atmosphere to 14 days. TBARS, pigment oxidation and bacterial load were inside the acceptable limit. The meat maintained its quality for 28 days of storage only when lambs were fed with the 1000 mg/kg dietary supplement, though the bacterial load was at the limit of acceptability.     

Effect of feeding fat sources on the quality and composition of lipids of precooked ready-to-eat fried chicken patties

The effect of feeding fat sources on the quality and composition of lipids of raw meat and precooked ready-to-eat fried chicken patties was studied. Two homogeneous groups of broilers were fed with animal fats and vegetable oils, respectively. A traditional technology (flash-frying and humid steam-convection oven cooking) was employed to produce the patties. Lipid hydrolysis (total fatty acids, free fatty acids and diacylglycerols) and oxidation (peroxide value (POV) and cholesterol oxidation products (COPs)) were evaluated in the initial, intermediate and final products. Lipid hydrolysis and oxidation were more intense in ground raw meat obtained with animal and vegetable fat integration, respectively. However, these differences tended to decrease along the technological process, due to the addition of other ingredients and the oil absorption. Although flash-frying and humid steam-convection oven cooking promoted lipid degradation, the overall quality of the precooked chicken cutlets was acceptable (low POV and COPS values) and greatly depended on the quality of the raw meat and the frying oil.     

Change in α‐tocopherol contents,lipid oxidation and fatty acid profile in eggs enriched with linolenic acid or very long‐chain ω3 polyunsaturated fatty acids after different processing methods

The influences of dietary supplementation with α‐tocopheryl acetate (α‐TA) and of processing (by hard‐boiling and scrambling) of eggs enriched with ω3 fatty acids, either very long‐chain ω3 polyunsaturated fatty acids (VLC ω3 PUFAs) or linolenic acid (LNA), on fatty acid composition, α‐tocopherol content and lipid oxidation (thiobarbituric acid (TBA) values) were studied. Four dietary treatments were formulated from a basal diet containing 40 g kg^?1 linseed oil (LO) or fish oil (FO) combined with either 0 or 100 mg α‐TA kg^?1 of feed. Eggs from LO treatments were enriched with LNA and those from FO treatments were rich in VLC ω3 PUFAs. Neither processing nor dietary supplementation with α‐TA modified greatly the fatty acid profile of eggs. Dietary supplementation with α‐TA increased the α‐tocopherol content of eggs (187.2 versus 407.9 µg g^?1 dry matter). Eggs from FO treatments showed lower α‐tocopherol content than those from LO treatments (273.5 versus 321.6 µg g^?1 dry matter), and processing of eggs enriched with VLC ω3 PUFA reduced the α‐tocopherol content by a significant 16%. Moreover, processing of eggs increased lipid oxidation two‐ to nine‐fold. Oxidation levels of hard‐boiled eggs were 30.4% higher than those of scrambled eggs. TBA values in hard‐boiled and scrambled eggs were significantly reduced when 100 mg α‐TA kg^?1 of feed supplemented the diet only in those eggs enriched with VLC ω3 PUFA (from FO treatments). Copyright © 2003 Society of Chemical Industry