Effects of vitamin E and fish oil inclusion in broiler diets on meat fatty acid composition and on the flavour of a composite sample of breast meat

BACKGROUND: Enriching poultry meat with long‐chain n‐3 polyunsaturated fatty acids (LC n‐3 PUFA) can increase low population intakes of LC n‐3 PUFA, but fishy taints can spoil reheated meat. This experiment determined the effect of different amounts of LC n‐3 PUFA and vitamin E in the broiler diet on the fatty acid composition and sensory characteristics of the breast meat. Ross 308 broilers (120) were randomly allocated to one of five treatments from 21 to 42 days of age. Diets contained (g kg^?1) 0, 9 or 18 LC n‐3 PUFA (0LC, 9LC, 18LC), and 100, 150 or 200 mg LD ‐α‐tocopherol acetate kg^?1 (E). The five diets were 0LC100E, 9LC100E, 18LC100E, 18LC150E, 18LC200E, with four pens per diet, except 18LC100E (eight pens). Breast meat was analysed for fatty acids (uncooked) and sensory analysis by R‐index (reheated). RESULTS: LC n‐3 PUFA content (mg kg^?1 meat) was 514 (0LC100E) and 2236 (9LC and 18LC). Compared with 0LC100E, meat from 18LC100E and 18LC150E tasted significantly different, while 23% of panellists detected fishy taints in 9LC100E and 18LC200E. CONCLUSION: Chicken meat can be enriched with nutritionally meaningful amounts of LC n‐3 PUFA, but > 100 mg dl‐α‐tocopherol acetate kg^?1 broiler diet is needed to protect reheated meat from oxidative deterioration. Copyright © 2010 Society of Chemical Industry     

Vitamin E levels,thiobarbituric acid test and sensory evaluation of breast muscles from broilers fed α‐tocopheryl acetate‐ and β‐carotene‐supplemented diets

The objective of this study was to investigate the effect of dietary α‐tocopheryl acetate and β‐carotene supplementation on lipid oxidation of breast meat from broilers fed lard as the fat source. Supplementation of broilers with 100 mg kg^?1 α‐tocopheryl acetate increased the vitamin E levels in raw breast samples significantly (p < 0.05), whereas the presence of 1.5 mg kg^?1 dietary β‐carotene tended to decrease vitamin E deposition. The presence of vitamin E delayed lipid oxidation significantly, but thiobarbituric acid values of samples from broilers fed the β‐carotene‐supplemented diet did not differ from those of control samples. Vitamin E reduced sensory meat rancidity, whilst vitamin E, β‐carotene and their combination modified meat texture. The results show the effectiveness of dietary α‐tocopheryl acetate supplementation in protecting broiler meat against lipid oxidation. Copyright © 2004 Society of Chemical Industry     

Improving the Sensory and Oxidative Stability of Cooked and Chill‐Stored Lamb Using Dietary Rosemary Diterpenes

Two dietary rosemary extracts (DREs) containing diterpenes (carnosic acid and carnosol at 1:1 and 2:1 w:w) were tested in fattening lambs to stabilize the sensory quality of cooked and chill‐stored patties. A total of 63 lambs were fed freely for 80 ± 5 d with a basal diet supplemented or not with DRE. Minced leg meat from each lamb was used to make patty batches. The patties were cooked at 72 ºC for 2 min, aerobically packed, kept at 2 ºC for up to 4 d and then reheated. Sensory traits (color, odor, flavor, and texture), CIELab color, and lipid oxidation (assessed as TBARS) were determined. In a first experiment, the lamb diet was supplemented with 600 mg of 1:1‐DRE or 2:1‐DRE kg^?1 feed. The 1:1‐DRE diet delayed discoloration, flavor deterioration, and rancidity, while the 2:1‐DRE diet was ineffective in this respect. In a second experiment, 4 supplementation levels of 1:1‐DRE (0, 200, 400, and 600 mg kg^?1 feed) were compared. Flavor deterioration was delayed when the lamb diet was supplemented with at least 400 mg 1:1‐DRE kg^?1 feed. The effects of the diet on the odor, flavor, and color were corroborated by differences in TBARS and CIELab. The results obtained suggest that rosemary diterpenes and/or their active secondary compounds deposited in muscle can act as endogenous antioxidants in cooked lamb. The carnosol intake seems crucial in the antioxidant actions achieved through DRE. The use of rosemary antioxidants in animal feeding would allow meat‐based dishes to be preserved longer without adding preservatives.     

Diet with linseed oil and organic selenium yields low n‐6/n‐3 ratio pork Semimembranosus meat with unchanged volatile compound profiles

The aim of this was to improve n‐6/n‐3 ratio without affecting the volatile compounds profiles of pork. Different feeding strategies were designed for 60 Polish Landrace pigs with the goal to enhance the health attributes of Polish pork. Composition, colour, hardness, fatty acid contents and volatile compound profiles of the semimembranosus muscles were determined. Results showed that with the basic diet with the addition 3% of linseed oil, 100 mg kg^?1 of vitamin E and 1 mg kg^?1 of organic selenium, the level of polyunsaturated fatty acids (PUFA) in the meat samples was increased by 26% (P ≤ 0.05) as compared to the control. Principal component analysis (PCA) demonstrated that the aroma profile of semimembranosus muscles from pigs fed with the diet supplemented with 3% of linseed oil and 1 mg kg^?1 of organic selenium was close to that of control. Results demonstrated that healthy functional meats could be produced by designing feeding strategies.     

Vitamin D3 regulation of body fat,cytokines, and calpain gene expression

BACKGROUND: We conducted an in vivo experiment to determine whether vitamin D₃ acts as a fat synthesizer and/or meat tenderizer in mice. At 6 weeks of age, 20 male C57BL/6 wild‐type mice were randomly divided into two groups (10 mice per group) and fed a modified AIN93G diet with (vitamin D₃ diet) or without (basal diet) 10 IU 25‐OH‐cholecalciferol kg^?3 for 3 weeks. RESULTS: When vitamin D₃ was fed to mice for 3 weeks, body fat was significantly increased compared to mice fed a basal diet. There was, however, no difference in body weight between the two groups. Vitamin D₃ increased the gene expressions of pro‐inflammatory cytokines and peroxisome proliferator‐activated receptor gamma, but decreased interleukin‐15 in adipose tissue through nuclear vitamin D receptor and uncoupling protein‐2 signals. The muscle inducible nitrate oxide synthase content of mice fed vitamin D₃ was higher than those fed a basal diet, while muscle arginase l showed a reverse phenomenon. longissimuss dorsi muscle of vitamin D₃‐fed mice showed more severe fat deposition than those fed a basal diet. Vitamin D₃ amplified muscle u‐ and m‐calpain protein content and suppressed muscle calpastatin protein content. CONCLUSION: These findings suggest that vitamin D₃ can be used as a fat synthesizer and meat tenderizer in meat‐producing animals. Copyright © 2011 Society of Chemical Industry     

Iron fortification and parboiled rice quality: appearance,cooking quality and sensory attributes

BACKGROUND: Iron (Fe) fortification of parboiled rice increases both Fe concentration and bioavailability in milled grains (i.e. white rice). The aim of the present study was to evaluate parboiled rice fortified with 250 and 450 mg Fe kg^?1 paddy rice for its pre‐cooking appearance, cooking quality, basic sensory attributes and overall acceptance in comparison with unfortified parboiled rice in Thailand and local parboiled rice in Bangladesh. RESULTS: Fe fortification at 250 mg Fe kg^?1 paddy rice significantly elevated Fe concentration in white rice to as high as 19.1 mg Fe kg^?1 white rice, compared with 6.2 mg Fe kg^?1 white rice for unfortified parboiled rice, without any adverse impact on consumer acceptance based on the current preliminary assessment. The added Fe was well retained in the cooked rice, with significant residual value for human intake. Panellists in Thailand and Bangladesh did not detect significant differences in the acceptability of parboiled rice fortified at 250 mg Fe kg^?1 paddy rice compared with unfortified and local parboiled rice respectively. However, Fe fortification of parboiled rice at the higher level of 450 mg Fe kg^?1 paddy rice significantly intensified the yellow colour of the grain and changed the off‐flavour, chewiness and flakiness of the cooked Fe‐fortified parboiled rice. This resulted in a low acceptability ranking of parboiled rice fortified at 450 mg Fe kg^?1 paddy rice by panellists in both Thailand and Bangladesh. CONCLUSION: Fe fortification of parboiled rice at an appropriate level (e.g. 250 mg Fe kg^?1 paddy rice) is dosage‐effective and acceptable to rice consumers. Consumer acceptability of Fe‐fortified parboiled rice is closely related to pre‐cooking appearance, cooking quality and sensory attributes. Copyright © 2009 Society of Chemical Industry     

Nanoparticles of chromium picolinate enhance chromium digestibility and absorption

BACKGROUND: Trivalent chromium (Cr) is a trace element that is difficult to digest and absorb. The objective of this study was to determine whether reducing organic Cr to nanometre size would increase its digestibility. RESULTS: Forty‐eight 8‐week‐old female Sprague‐Dawley rats were randomly assigned to one of four dietary treatments: (1) basal diet (control); (2) basal diet plus 300 µg kg^?1 Cr as chromium chloride (CrCl₃); (3) basal diet plus 300 µg kg^?1 Cr as chromium picolinate (Crpic); (4) basal diet plus 300 µg kg^?1 Cr as nanoparticulate Crpic (nanoCrpic). NanoCrpic was prepared from Crpic with a particle size of 55–100 nm. The experiment lasted 48 days. Cr digestibility and serum Cr concentration were 1.66 and 1.96 times greater respectively in rats fed nanoCrpic than in rats fed Crpic (P < 0.05). The average daily gain was greater in rats fed nanoCrpic or Crpic than in control rats (P < 0.05). The high‐density lipoprotein content increased while the very‐low‐density plus low‐density lipoprotein content decreased in rats fed nanoCrpic as compared with rats fed Crpic or CrCl₃ (P < 0.05). CONCLUSION: This study indicates that reducing the particle size of Crpic enhances Cr digestibility and absorption in rats and alters some blood metabolite concentrations. Copyright © 2009 Society of Chemical Industry     

Carcass characteristics and meat quality of broilers fed periwinkle flesh (Pachymelania aurita), palm kernel cake and oil‐based rations

The effect of supplementation of palm kernel oil in periwinkle flesh and palm kernel cake‐based diets on carcass characteristics and meat quality of broilers was evaluated. Birds were assigned to five dietary treatments in a completely randomized design. The first diet, which was the control, contained 20 mg kg^?1 fishmeal but it did not contain palm kernel cake and periwinkle flesh. The second diet contained 20 mg kg^?1 fishmeal, 250 mg kg^?1 palm kernel cake but no periwinkle flesh. The third diet contained 60 mg kg^?1 periwinkle flesh, 250 mg kg^?1 palm kernel cake and no fishmeal. Present in the fourth diet were 250 mg kg^?1 palm kernel cake, 30 mg kg^?1 periwinkle flesh, no fishmeal and 20 mg kg^?1 palm kernel oil. Similarly, the fifth diet contained 250 mg kg^?1 palm kernel cake, 30 mg kg^?1 periwinkle flesh, no fishmeal and 40 mg kg^?1 palm kernel oil. Carcass measures and cuts were significantly influenced (P < 0.05) by dietary treatments. Diets 2, 3 and 5 gave significantly higher plucked dressed weights, total edible meat and total bone weights, respectively. Also carcass cuts were significantly increased (P < 0.05) in birds on periwinkle and palm kernel oil diets, with abdominal fat being highest in diet 5 having 40 mg kg^?1 palm kernel oil. However, proximate composition, physical and sensory properties were not significantly (P < 0.05) influenced by dietary treatment. Results showed that carcass characteristics improved as compared to the control group. Copyright © 2005 Society of Chemical Industry     

Stability,sensory quality,texture properties and nutritional value of fish oil‐enriched spreadable fat

A Correction has been published for this article in Journal of the Science of Food and Agriculture 84(15):2142 (2004). The intake of omega‐3 long‐chain polyunsaturated fatty acids (PUFAs) in the typical Western diet is usually below the recommended level. Without radical changes of eating patterns the diet may be enhanced by enrichment of foods with unhydrogenated fish oil, which is the richest source of the long‐chain omega‐3s, eicosapentaenoicacid (EPA) and docosahexaenoicacid (DHA). The aims of the study were to establish the sensorily acceptable fish oil enrichment level of a reduced‐fat spread, to enhance the omega‐3 long‐chain PUFA content and to evaluate the enriched spread's stability during 3 months of storage (6°C, limited exposure to light and air). Samples were prepared in an industrial pilot plant. Overall sensory quality, intensity of fishy flavour, texture properties (sensory and instrumental), peroxide value, acid number and fatty acids composition were measured. A spread enriched by addition of 30.0 g kg^?1 of unhydrogenated fish oil could be stored for up to 3 months without significant decrease of the measured stability indicators. A daily portion of this enriched spread (30 g) would provide 0.25 g of EPA and DHA, significantly increasing long‐chain omega‐3 levels in the average diet. Copyright © 2004 Society of Chemical Industry     

Lipid and flavour quality of stored breast meat from broilers fed marine algae

In the current study, broilers were fed either 2·8 or 5·5% natural golden marine algae (MA) or 2·1% menhaden oil in an effort to produce an n-3 fatty acid (FA) enriched broiler breast product with acceptable flavour and lipid quality. Previously cooked or raw breast samples were stored at -23°C for 82 d and evaluated at intervals for flavour and TBA values. All treatments significantly increased breast n-3 FA content compared to samples from control-fed birds. The greatest n-3 FA deposition (212 mg kg⁻¹) was achieved by feeding 5·5% MA. All dietary n-3 FA significantly reduced flavour scores compared to samples from control-fed birds, although 2·8% MA samples were still considered acceptable by consumer panelists. Deterioration of flavour quality during storage of previously cooked samples was accelerated by all n-3 FA treatments except 2·8% MA. The rate of TBA production during storage of cooked breast meat was increased by n-3 FA, but this was curtailed by storing samples raw. These data indicate that 2·8% MA is useful for enhancing poultry tissue n-3 FA with minimal compromise in flavour or lipid quality, thus yielding a product that may serve as a substitute for fish in the diet. © 1988 Society of Chemical Industry     

Effect of dietary supplementation with vitamin E on characteristics of vacuum‐packed lamb

The effect of dietary vitamin E supplementation on lamb during vacuum‐packed storage was studied. Thirty‐six weaned male Manchego breed lambs were offered four dietary treatments (20, 270, 520 and 1020 mg vitamin E kg^?1 feed). Lambs were fed the vitamin E‐supplemented diet from 13 until 26 kg live weight. Pieces of M. longissimus dorsi were stored under vacuum at 2 ± 1 °C in the dark and meat quality was assessed after 5, 14 and 28 days of storage. Dietary supplementation significantly increased the α‐tocopherol concentration in the muscle (P < 0.001). Initially, lipid oxidation, meat colour and bacterial load were similar in all groups. In meat of non‐supplemented lambs the thiobarbituric acid reactive substance value increased throughout storage, whereas in meat of supplemented lambs it did not increase. Meat pigments and discolouration proportion were significantly affected by storage time (P < 0.001). The bacterial load was low initially, but after 28 days of storage it was close to 7 log₁₀ colony‐forming units (cfu) cm^?2 and Enterobacteriaceae surpassed the limit of acceptability of 2.5 log₁₀ cfu cm^?2, making the lamb unsuitable for human consumption. Meat of supplemented lambs displayed less lipid oxidation than that of their non‐supplemented counterparts, while meat colour and bacterial load were not affected by supplementation. Copyright © 2007 Society of Chemical Industry     

The effect of dietary α-tocopherol supplementation and antioxidant spraying on colour stability and lipid oxidation of turkey meat

Vitamin E was supplemented in the diet (250 mg kg^?1) of turkeys or sprayed directly on turkey meat. Turkey breast muscles were cut into 1.5 cm slices, wrapped with oxygen-permeable film and stored at 2–4°C for 1 week. Colour coordinates (L*, a*, b*), pH and reflectance values between 630 and 580 nm were determined at various times post mortem, TBARS (thiobarbituric acid-reactive substances) values and vitamin E content were assessed immediately after slaughter and at 7 days post mortem for vitamin E-supplemented, sprayed and control groups. Vitamin E supplementation or antioxidant spraying resulted in a lower myoglobin oxidation (P < 0.05) and a higher a* value at day 2, but not thereafter. No differences in TBARS values and ultimate pH were detected. When peroxidation was induced experimentally by addition of an activated mixture, vitamin E supplemented or antioxidant-sprayed samples exhibited lower TBARS values than the controls. Vitamin E supplementation in the diet or antioxidant spraying of meat produced a temporary delay in the rate of discoloration of turkey meat.     

Dietary purines in vegetarian meat analogues

BACKGROUND: The meat alternatives market offers a wide range of products resembling meat in taste, flavour or texture but based on vegetable protein sources. These high protein–low purine foods may find application in a low purine or purine‐free diet, which is sometimes suggested for subjects with increased serum urate levels, i.e. hyperuricaemia. RESULTS: We determined purine content (uric acid, adenine, guanine, hypoxanthine, xanthine) in 39 commercially available meat substitutes and evaluated them in relation to their protein content. Some of the products contained a comparable sum of adenine and hypoxanthine per protein as meat. Analysis of variance showed an influence of protein source used. Mycoprotein‐based products had significantly higher contents (2264 mg kg^?1) of adenine and hypoxanthine per kg of 100% protein than soybean‐based products (1648 mg kg^?1) or mixtures consisting of soybean protein and wheat protein (1239 mg kg^?1). CONCLUSION: Protein‐rich vegetable‐based meat substitutes might be generally accepted as meat alternatives for individuals on special diets. The type of protein used to manufacture these products determines the total content of purines, which is relatively higher in the case of mycoprotein or soybean protein, while appearing lower in wheat protein and egg white‐based products. These are therefore more suitable for dietary considerations in a low‐purine diet for hyperuricaemic subjects. Copyright © 2010 Society of Chemical Industry     

Effects of dietary supplementation of cysteamine on growth performance,carcass quality,serum hormones and gastric ulcer in finishing pigs

A study was conducted to determine the effects of graded levels of dietary inclusion of a cysteamine (Cs) preparation on growth performance, carcass quality, plasma hormone levels, gastric pH and occurrence of gastric ulcer in finishing pigs. A total of 384 Landrace × Large White finishing pigs, (192 gilts and 192 barrows) with an average initial body weight of 66.05 ± 0.623 kg (mean ± SEM) were randomly divided into 24 floor pens, with eight gilts and eight barrows in each pen (9.2 m²) as one experimental unit. The 24 pens of pigs were randomly allocated to one of three diets: (1) a maize/soybean meal basal diet; (2) the basal diet plus 30 mg Cs kg^?1 diet; and (3) the basal diet plus 50 mg Cs kg^?1 diet. Dietary supplementation of Cs had quadratic effects (P < 0.01) on final body weight and average daily gain, with optimal responses occurring at 30 mg kg^?1. Dietary supplementation of Cs quadratically improved (P < 0.01) average daily feed intake and feed/gain ratio, with optimal responses occurring at 30 mg kg^?1. Dietary supplementation of Cs had a quadratic effect (P < 0.01) on muscle RNA/DNA ratio. Furthermore, dietary supplementation of Cs reduced (P < 0.05) back‐fat thickness. Dietary supplementation of Cs had quadratic effects (P < 0.05) on plasma glucagon and T₃ hormone levels, with optimal responses occurring at 30 mg kg^?1, but had no effect (P > 0.05) on plasma growth hormone, insulin and T₄ levels. There were no apparent pathological changes seen in the stomach mucosa of pigs fed at 30 mg Cs kg^?1 compared with the control diet. It is concluded that a low dose of dietary inclusion of Cs at 30 mg kg^?1 can improve growth performance and carcass quality without adverse effects on the stomach in finishing pigs. Copyright © 2005 Society of Chemical Industry     

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.     

Effect of solid content and composition of hydroxypropyl methylcellulose-lipid edible coatings on physico-chemical and nutritional quality of 'Oronules' mandarins

BACKGROUND: Citrus fruit represent an important source of vitamin C, as well as other bioactive compounds. Edible coatings have the potential to extend shelf life of citrus by providing a semi‐permeable barrier to water and gases, which depends on coating composition, solid content (SC), and cultivar. However, little is known about the effect of coatings on citrus nutritional quality. This work studies the effect of coating composition and SC of hydroxypropyl methylcellulose (HPMC)–beeswax (BW)–shellac coatings on the physico‐chemical, sensory and nutritional quality of ‘Oronules’ mandarins. Coatings prepared at the same lipid content differed in the BW:shellac ratio (1:3 and 3:1) and SC of the formulations (40 and 80 g kg^?1). RESULTS: The coating with 1:3 BW:shellac ratio and 80 g kg^?1 SC was the most effective controlling weight loss, although it was less effective than the commercial wax tested. Increasing SC had a greater effect than the BW:shellac ratio in fruit internal atmosphere and sensory quality, with the presence of off‐flavour when coatings were applied at 80 g kg^?1 SC. Nutritional quality was not affected by the application of the different treatments. CONCLUSION: HPMC–lipid coatings have the potential to extend shelf life of ‘Oronules’ mandarins. However, care should be taken controlling formulation SC to avoid the build‐up of off‐flavour. Copyright © 2011 Society of Chemical Industry     

Chemical,biological and sensory evaluation of pasta products supplemented with α‐galactoside‐free lupin flours

α‐Galactoside‐free lupin flour has been used to supplement durum wheat semolina flour in order to increase the nutritive value of pasta products. Supplemented pasta products had a shorter cooking time, higher cooking water absorption, cooking loss and protein loss in water than control pasta prepared with only semolina. Sensory evaluation of cooked pastas showed that products supplemented with 80 g kg^?1 of α‐galactoside‐free Lupinus angustifolius var. Emir flour or with 100 g kg^?1 of α‐galactoside‐free Lupinus angustifolius var. Troll flour showed the same acceptability by panellists as the semolina pasta. These levels of supplementation were selected for further studies. The cooked α‐galactoside‐free lupin/semolina pastas showed higher amounts of protein, dietary fibre, calcium, phosphorus, magnesium, zinc and antioxidant capacity than control pasta and a reasonable level of vitamin B₁, vitamin B₂ and vitamin E. Biological assessment of cooked pastas indicated that the true protein digestibility did not change after the fortification of semolina but protein efficiency ratio increased sharply in the pasta supplemented with α‐galactoside‐free lupin flours (2.07 and 1.92 for Emir and Troll lupin varieties, respectively) in comparison with the control pasta (1.11). It is concluded that the α‐galactoside‐free lupin flours are an adequate ingredient to improve the nutritional quality of pasta products without adding flatulent oligosaccharides. Copyright © 2006 Society of Chemical Industry     

Maternal dietary conjugated linoleic acid is not directly toxic for the developing chick embryo,but causes embryo mortality by altering fatty acid composition of the egg yolk in the chicken

BACKGROUND: Conjugated linoleic acid (CLA) was shown to cause embryo mortality when added into chicken diets. The objective of this study was to determine if CLA accumulation in yolk was directly responsible for embryo mortality. MATERIAL AND METHODS: Forty‐two 30‐week‐old hens were assigned to seven groups and fed a diet containing 5 g kg^?1 canola oil (Group A), 5 g kg^?1 CLA (Group B), 5 g kg^?1 CLA plus 20 g kg^?1 canola oil (Group C), 5 g kg^?1CLA plus 30 g kg^?1 canola oil (Group D), 5 g kg^?1 CLA plus 40 g kg^?1 canola oil (Group E), 10 g kg^?1 CLA plus 40 g kg^?1 canola oil (Group F) or 20 g kg^?1 CLA plus 40 g kg^?1 canola oil (Group G) for 22 days. Collected eggs were held at 15 °C for 24 h, and then incubated. For fatty acid analysis, three eggs were collected on the 22^nd day of the study. RESULTS: After the sixth day, embryonic mortality was 100% in eggs from Group B versus 2, 30, 21, 4, 0, and 9% in groups A, C, D, E, F and G, respectively. The ratio of SFA/UFA of yolks from groups A, B, C, D, E, F and G was 0.64, 1.53, 1.07, 1.06, 1.08, 1.05 and 1.13, respectively. Relative levels (%) of CLA in the eggs from the groups A, B, C, D, E, F and G were 0.12, 2.29, 1.68, 1.80, 1.76, 3.04, and 5.25%, respectively. CONCLUSION: This study showed that CLA was not directly toxic for developing embryo, but caused mortality in the fertile eggs by increasing the ratio of SFA to UFA in egg yolk. Copyright © 2009 Society of Chemical Industry     

Effect of oil sources and vitamin E levels in the diet on the composition of fatty acids in rooster thigh and chest meat

The aim of this study was to evaluate the inclusion of different oil sources and dietary supplementation with vitamin E on the composition of fatty acids in rooster meat. Two hundred and forty 30‐week‐old White Leghorn roosters were distributed in a completely randomized factorial arrangement of 5 × 2, using five oil sources (sunflower, soybean, canola, linseed and fish) and two levels of antioxidant (30 and 400 mg vitamin E kg^?1 of diet). The intake of fish and canola oil in the diet reduced (P < 0.05) the content of saturated and unsaturated fatty acids in the thigh meat. Amongst the unsaturated fatty acids in the thigh, the fish and canola oil reduced (P < 0.05) the level of ω6 fatty acid, with a consequent decrease in the ratio ω6:ω3. The diet with fish oil increased (P < 0.05) the content of C22:6ω3 in the thigh meat. The use of linseed oil resulted in a significant reduction of the ratio of ω6:ω3 fatty acid in the thigh. The use of soybean oil in the diet increased (P < 0.05) the content of saturated and unsaturated fatty acids in the thigh, specifically in the content of ω6. The inclusion of vitamin E increased the polyunsaturated fatty acids in the chest meat, such as C18:3ω3, C20:5ω3 and C22:6ω3. Copyright © 2004 Society of Chemical Industry     

Effect of dietary oil source on the flavour and the colour and lipid stability of lamb meat

This study investigated the influence of five sources of dietary oil (linseed oil (LO), fish oil (FO), a protected lipid supplement (PLS, 18:2 to 18:3 ratio 3:1), fish oil/marine algae (FOMA) and PLSMA) on the colour and lipid stability of lamb muscle and the flavour of grilled loin chops. LO produced the highest proportion of 18:3n−3 in muscle phospholipid, the highest ratings for lamb flavour intensity and overall liking and the lowest ratings for abnormal flavour intensity. PLS increased the proportion of 18:2n−6 which reduced lamb flavour intensity and increased abnormal lamb flavour intensity. Diets containing FO or MA increased proportions of the longer chain n−3 fatty acids and similar reduced ratings for lamb flavour as the PLS diet. FO-containing diets increased fishy flavour notes, especially when in combination with MA. ‘Putty’ and ‘fish oil’ odours were recognised as being present more frequently in cooked subcutaneous lamb fat from lambs fed FO and FOMA than other diets. Lambs fed MA, FO and the combination of the two produced meat that was oxidatively less stable and had a reduced colour and lipid oxidative shelf-life, which was at least partially due to the lower vitamin E content of the muscle.

These results have significant implications for the formulation of diets that may improve nutritional ratios in lamb meat but which adversely affect flavour and meat stability.