Effect of processing and storage on the fatty acid composition of n‐3 or n‐6 fatty acid‐enriched eggs

Fresh eggs from hens fed diets supplemented with 4% linseed oil (LO) or sunflower oil (SO) were either directly submitted to pasteurisation, hard‐boiling or scrambling processing, or first submitted to refrigerated storage at 4 °C for 60 day and then to processing. Fresh LO eggs showed higher (P ≤ 0.05) proportions of monounsaturated fatty acids (MUFAs) and n‐3 polyunsaturated fatty acids (PUFAs), but lower (P ≤ 0.05) proportions of saturated fatty acids (SFAs), PUFAs and n‐6 PUFAs than the SO eggs. Storage decreased (P ≤ 0.05) the proportion of PUFAs and increased (P ≤ 0.05) that of MUFAs in egg yolks from both treatments. The pasteurisation process had no effect on the fatty acid composition of fresh eggs from both treatments, but increased (P ≤ 0.05) n‐6 PUFAs and decreased (P ≤ 0.05) n‐3 PUFAs in stored LO eggs. Hard‐boiling and scrambling modified the fatty acid composition of fresh and stored eggs from both treatments by decreasing (P ≤ 0.05) the proportion of PUFAs, particularly of the very long‐chain n‐3 eicosapentaenoic, docosapentaenoic and docosahexaenoic PUFAs. LO eggs showed a higher susceptibility to fatty acid modification upon processing as compared to the SO eggs.     

Effect of α‐tocopherol and α‐tocotrienol on the performance of Chilean hazelnut oil (Gevuina avellana Mol) at high temperature

The high temperature antioxidant efficiency of α‐tocopherol, α‐tocotrienol and a mixture of both on hazelnut oil were evaluated. Crude hazelnut oil (HZO), crude hazelnut oil treated with alumina (THZO), as well as three samples of THZO to which 150 mg kg^?1 of α‐tocopherol, 140 mg kg^?1 of α‐tocotrienol or a mixture containing 70 mg kg^?1 of α‐tocopherol and 70 mg kg^?1 of α‐tocotrienol, were added and submitted to thermal treatment at 180°C for 18 h. The addition of tocols to THZO decreased the formation of polar compounds and increased its oxidative stability in all the systems studied. However, α‐tocopherol showed a higher antioxidant capacity than α‐tocotrienol at high temperature. In addition, α‐tocotrienol showed a more rapid degradation rate than α‐tocopherol under the conditions studied. Copyright © 2004 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     

Ameliorative effect of α‐tocopherol on monosodium glutamate‐induced cardiac histological alterations and oxidative stress

BACKGROUND: Chronic oral intake of high doses of monosodium glutamate (MSG) causes oxidative stress. Oxidative stress plays an important role in the development of cardiac dysfunction and injury. Supplementation with α‐tocopherol protects the body against oxidative stress and its related complications. This study was proposed to examine the protective effect of α‐tocopherol against MSG‐induced biochemical and histological alterations in blood and cardiac tissue of rats for a period of 180 days. RESULTS: Chronic oral administration of MSG (4 g kg^?1) caused oxidative stress that was manifested by significant increase (P < 0.05) in malondialdehyde, conjugated dienes and by the decrease in the activities of superoxide dismutase, catalase, reduced glutathione, glutathione peroxidase and glutathione S‐transferase in cardiac tissue. The significantly increased (P < 0.05) activities of aspartate transaminase, creatine phosphokinase and lactate dehydrogenase in serum suggested a cardiac functional disorder. Moreover, heart muscle fibers showed cloudy swelling, fiber separation and vascular congestion. Administration of α‐tocopherol (200 mg kg^?1) significantly (P < 0.05) attenuated the MSG‐induced biochemical alterations in serum and cardiac tissue. α‐Tocopherol also prevented the pathological changes in cardiac tissue when compared with the MSG‐treated group. CONCLUSION: Our findings suggest that α‐tocopherol may have a protective effect against MSG‐induced cardiotoxicity, possibly through its antioxidant activity. Copyright © 2012 Society of Chemical Industry     

In vitro inhibitory effects of cranberry bean (Phaseolus vulgaris L.) extracts on aldose reductase, α‐glucosidase and α‐amylase

The in vitro inhibitory activities of different seed extracts prepared from cranberry bean mutant SA‐05 and its wild‐type variety Hwachia against aldose reductase, α‐glucosidase and α‐amylase were examined. The results indicated that the polyphenolics‐rich extracts obtained using 800 g kg^?1 methanol and 500 g kg^?1 ethanol demonstrated inhibitory activities against aldose reductase (IC₅₀ of 0.36–0.46 mg mL^?1) and α‐glucosidase (IC₅₀ of 1.32–1.94 mg mL^?1). The 500 g kg^?1 ethanol extracts also showed α‐amylase inhibitory activities (IC₅₀ of 70.11–80.22 μg mL^?1). Subsequent extracts, prepared further with NaCl and H₂O from precipitates of 800 g kg^?1 methanol or 500 g kg^?1 ethanol extracts, exhibited potent α‐amylase inhibitory activities (IC₅₀ of 17.68–38.68 μg mL^?1). A combination of 500 g kg^?1 ethanol extraction plus a subsequent H₂O extraction produced highest polyphenolics and α‐amylase inhibitors. The SA‐05 α‐amylase inhibitor extracts showed greater inhibitory activities than that of Hwachia. Thus, cranberry bean mutant SA‐05 is an advantageous choice for producing anti‐hyperglycaemic compounds.     

Effect of different sources of dietary omega‐3 fatty acids on general performance and fatty acid profiles of thigh,breast, liver and portal blood of broilers

One hundred and sixty‐eight 1‐day‐old Cobb broiler chickens were randomly assigned to 12 broiler cages to determine the dietary effect of different sources of oils rich in long‐chain omega‐3 polyunsaturated fatty acids (LCω3PUFA). The following oils were added to the feed at a concentration of 12.5 g kg^?1: a highly refined seal blubber oil (SBO) containing 225 g kg^?1 LCω3PUFA; a fish oil (FO) concentrate containing >800 g kg^?1 LCω3PUFA in the form of triglycerides; and an FO concentrate containing >600 g kg^?1 LCω3PUFA in the form of ethyl esters. Fatty acid profiles of the breast and thigh meat were measured in order to determine the deposition of LCω3PUFA into the body tissues, whilst fatty acid profiles of the liver and the portal blood were taken in order to deduce consequences of the different ester forms on the absorption process. A triangular sensory evaluation was performed on the breast meat. The levels of LCω3PUFA in all tissues and the portal blood reflected the concentrations of LCω3PUFA in the diets. The sensory properties of the breast meat were negatively influenced by ethyl ester supplementation only. Copyright © 2004 Society of Chemical Industry     

Beneficial effect of the unsaponifiable matter from rice bran on oxidative stress in vitro compared with α‐tocopherol

Unsaponifiable matter (UM) was prepared from rice bran using n‐hexane extraction followed by removal of its fatty acid methyl ester with supercritical CO₂ under heat‐stable conditions. The UM was made up of 1% of vitamin E isomers, 28% of γ‐oryzanol and 71% of uncharacterized compounds. The aim of this study was to determine the antioxidant activities of the UM, using α‐tocopherol (α‐T) as a positive control, by measuring the Fe³⁺‐reducing antioxidant power (FRAP), 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH^?) free‐radical‐scavenging property and lipid peroxidation in rat liver microsomes. In addition, the effects of the UM on the tert‐butyl hydroperoxide (t‐BOOH)‐induced cytotoxicity in cultured rat hepatocytes were also investigated. In FRAP assay and DPPH^? free‐radical‐scavenging assay, the results were expressed g^?1α‐T or g^?1 UM. The amount of UM used in lipid peroxidation assay and cytotoxicity assay was the amount required to have equal amounts of total vitamin E isomers in the sample and the control α‐T. The UM, as well as α‐T, exhibited significant antioxidant activities in FRAP, radical‐scavenging and membrane‐lipid oxidation. The FRAP value for total vitamin E isomers in the UM (TVEIUM) was 9.1 times higher than that for α‐T. In terms of their capacities to perform radical‐scavenging and lipid peroxidation, both TVEIUM and α‐T showed similar antioxidant activities. In experiments using cultured rat hepatocytes, the t‐BOOH‐induced lactate dehydrogenase release was significantly inhibited by the addition of 63.5 and 160 µg ml^?1 of TVEIUM treatments (84 and 89%, respectively), and that of 63.5 and 160 µg ml^?1 of α‐T treatment (88 and 93%, respectively). The antioxidant function against oxidative stress of the UM prepared from rice bran may extend its use to being a potential dietary supplement. Copyright © 2004 Society of Chemical Industry     

Analytical evaluation of two monovarietal virgin olive oils cultivated in the south of Tunisia: Jemri‐Bouchouka and Chemlali‐Tataouin cultivars

BACKGROUND: The characterisation of virgin olive oils from two Tunisian cultivars, growing in the Tataouin zone, namely Jemri‐Bouchouka, a rare olive cultivar, and Chemlali‐Tataouin, was carried out. Several analytical parameters were evaluated; these include quality index, fatty acids, phenolic, chlorophyll, carotenoid, squalene, α‐tocopherol compositions and oxidative stability. RESULTS: Jemri‐Bouchouka olive oil had the highest value of oleic acid (74.50%) while Chemlali‐Tataouin was characterised by a high percentage of palmitic acid (14.75%), which makes this oil freeze at a low temperature. On the other hand, Jemri‐Bouchouka oil was characterised by a low phenolic and α‐tocopherol content (267.72 mg GAE kg^?1 and 278.34 mg kg^?1, respectively). Ten phenolic compounds were identified. The main phenols found in the two olive oils were oleuropein aglycon and pinoresinol. All phenolic compounds showed significant correlations with oxidative stability. CONCLUSION: The analytical parameters of virgin olive oil that were determined in this study were greatly influenced by cultivar. © 2012 Society of Chemical Industry     

Screening grape seeds recovered from winemaking by‐products as sources of reducing agents and mammalian α‐glucosidase and α‐amylase inhibitors

Grape seeds collected from vinification of various grape varieties were extracted by supercritical CO₂ for oil recovery. The defatted residues thus obtained were considered as a re‐utilisable co‐product and assessed for phenolic content, reducing capacity and inhibitory activities against mammalian α‐amylase and α‐glucosidase enzymes. Supercritical CO₂ treatment led to higher recovery of anthocyanins. Reducing capacity of phenolic extracts reached up to ~2200 mmolFe(II) kg^?1, much higher than that of various natural phenolic sources. The anthocyanin‐rich extracts showed the highest inhibitory effectiveness towards α‐glucosidase (I₅₀ value equal to ~40 μg gallic acid equivalents (GAE)/mL ~ half than acarbose). Inhibitory effectiveness towards α‐amylase activity was similar among grape varieties, with I₅₀ values comparable to that of acarbose and correlated with proanthocyanidin contents. These results could pave the way for an efficient processing of grapes, including cascade processes, namely: winemaking, oil extraction from recovered grape seeds and phenolic extraction from defatted grape seeds as potential cost‐effective nutraceuticals.     

Composition of subcutaneous fat from dry‐cured Iberian hams as influenced by pig feeding

The triacylglycerol and free fatty acid composition and volatile profile of subcutaneous fat of three batches of dry‐cured lberian hams from pigs fed in an extensive system based on acorn and pasture (‘montanera’: MONT) or in confinement with a control diet (FEED) or a 100 mg α‐tocopheryl acetate kg^?1 enriched diet (VITE) were investigated. Triacylglycerol of subcutaneous fat of hams from pigs fed on acorn and pasture (MONT) was more unsaturated, with larger percentages of monounsaturated and polyunsaturated fatty acids, than triacylglycerol of subcutaneous fat of hams from pigs fed on concentrate feeds (FEED and VITE). However, the trend of oxidative processes was quite similar in the groups that contained antioxidants (‘montanera’ and α‐tocopherol supplementation); namely, the highest volatile contents were found in subcutaneous fat of hams from pigs fed on acorn and pasture, while α‐tocopherol supplementation gave rise to a different profile of volatile compounds in comparison with the control diet. Therefore antioxidant presence could contribute to a high intensity and quality of aroma of these hams. © 2001 Society of Chemical Industry     

A critical review of methodologies used in determination of relative bio‐availability ratio of RRR‐α‐tocopheryl acetate and all‐rac‐α‐tocopheryl acetate

Bio‐availability of different α‐tocopherol forms in livestock animals is measured by the increase in plasma or tissue concentrations of α‐tocopherol after oral administration. It is generally accepted that RRR‐α‐tocopheryl acetate (natural source vitamin E derived from vegetable oil) has a higher bio‐availability compared to all‐rac‐α‐tocopheryl acetate (synthetic vitamin E, i.e. α‐tocopherol produced by chemical synthesis). However, different bio‐availability ratios have been reported in the literature. The major reason for conflicting results in literature studies was the inability to separate the proportion of α‐tocopherol originating from test materials, from the proportion of α‐tocopherol originating from basal dietary ingredients and pre‐feeding. This causes significant variability. For bio‐availability determination, a baseline or control treatment is essential. The estimation of bio‐availability without correction for basal vitamin E status will lead to incorrect interpretation of the results. When using proper methodologies, it is possible to correct for the impact of α‐tocopherol intake from basal ingredients and α‐tocopherol originating from pre‐feeding, therefore yielding results reflecting the true relative bio‐availability of different α‐tocopherol substances. When reviewing literature data a critical evaluation of the method used in determination of relative bio‐availability is recommended. Copyright © 2010 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     

α‐Eleostearic acid is more effectively metabolized into conjugated linoleic acid than punicic acid in mice

BACKGROUND: The objective of this study was to investigate the metabolism of α‐eleostearic acid (α‐ESA, cis9,trans11,trans13‐18:3) and punicic acid (PA, cis9,trans11,cis13‐18:3) and to compare the relative conversion efficiency of these fatty acids into conjugated linoleic acids (CLAs) in mice. RESULTS: Twenty‐four male ICR mice were fed either a control diet or one of two experimental diets supplemented with 10 g kg^?1α‐ESA or PA in the form of triacylglycerols for 6 weeks. The accumulation of PA in all tissues examined was significantly higher than α‐ESA; in both groups it was found that cis9,trans11‐conjugated linoleic acid (cis9,trans11‐18:2) was detected in all tissues examined. The relative conversion rate of α‐ESA into cis9,trans11‐18:2 was significantly higher than that of PA. The highest conversion rate of α‐ESA was found in adipose tissue (91.8%), spleen (91.4%) and kidney (90.7%), and the lowest in the heart (84.6%). The highest conversion rate of PA occurred in the liver (76.2%) and the lowest occurred in the heart (54.5%). CONCLUSION: The present results indicate that both α‐ESA and PA are effectively metabolized into cis9,trans11‐18:2 in mice. These conjugated dietary fatty acids might be useful sources of CLAs in tissues owing to the natural abundance of α‐ESA and PA in some seeds. Copyright © 2009 Society of Chemical Industry     

Quality characteristics of refined,bleached and deodorized palm olein and banana chips after deep‐fat frying

The changes in quality characteristics of refined, bleached and deodorized (RBD) palm olein used for deep‐fat frying of banana chips (180°C for 3 min at 17 min intervals for 2 h day^?1, to give six fryings per day and 30 fryings over five consecutive days) were studied. Four frying systems were used: RBD palm olein without antioxidant (system 1); RBD palm olein with 0.2 g kg^?1 α‐tocopherol (system 2); RBD palm olein with 1 g kg^?1 oleoresin rosemary (system 3); and RBD palm olein with the combination of 0.1 g kg^?1 α‐tocopherol + 0.5 g kg^?1 oleoresin rosemary (system 4). Fried oil samples were analysed for fatty acid composition, peroxide value (PV), anisidine value (AnV), totox value, free fatty acids (FFA) value, iodine value, at 232 and 268 nm, colour and viscosity. The crispness and sensory evaluation of the banana chips fried in this study were also evaluated. The results showed that RBD palm olein with added antioxidant reduced PV, AnV, totox value, at 232 and 268 nm, FFA and viscosity. The order of effectiveness in inhibiting oil oxidation in RBD palm olein was: oleoresin rosemary > α tocopherol + oleoresin rosemary > α‐tocopherol > control. For the crispness, the force values of banana chips fried in all systems were comparable. Sensory evaluation of fried banana chips for each system showed that there was no significant (P > 0.05) difference in terms of colour, flavour, odour, texture and overall acceptability. Copyright © 2003 Society of Chemical Industry     

Functional and sensory properties of hen eggs with modified fatty acid compositions

Foaming, emulsifying, gelling, and sensory properties of fresh and stored hen eggs fed with a diet supplemented with flax oil (FO), rapeseed oil (RO), fish oil (FISH), and by-product from black currant processing (BC) were investigated. With these diets, the ω6/ω3 fatty acid ratio of eggs varied from 1.5 to 5.8, while the ratio for eggs in the control group was 6.2. Compared to eggs in the control group, FO supplementation in the feed had statistically significant influences on the foaming properties of the fresh eggs. Eggs stored for 21 days lost part of their foaming properties in FISH oil supplemented group, but the foaming properties in all test groups were technically acceptable. The emulsifying properties of eggs in FO and FISH supplemented feeding groups were statistically different compared to control group. In boiled eggs, flax oil and fish oil supplementation induced off flavours in eggs, but no changes between the control group and test groups were found in the sensory properties of mayonnaise preparations. These results suggest that the egg processing industry may produce egg-based products using oil-supplemented eggs without major problems in functional or sensory properties.     

Effect of substituting fresh‐cut perennial ryegrass with fresh‐cut white clover on bovine milk fatty acid profile

BACKGROUND

Including forage legumes in dairy systems can help address increasing environmental/economic concerns about perennial ryegrass monoculture pastures. This work investigated the effect of substituting fresh‐cut grass with increasing quantities of fresh‐cut white clover (WC) on milk fatty acid (FA) profile and transfer efficiency of dietary linoleic (LA) and α‐linolenic (ALNA) acids to milk fat. Three groups of three crossbred dairy cows were used in a 3 × 3 crossover design. Dietary treatments were 0 g kg^?1 WC + 600 g kg^?1 grass, 200 g kg^?1 WC + 400 g kg^?1 grass, and 400 g kg^?1 WC + 200 g kg^?1 grass. All treatments were supplemented with 400 g kg^?1 concentrates on a dry matter basis. Cows had a 19‐day adaptation period to the experimental diet before a 6‐day measurement period in individual tie stalls.

RESULTS

Increasing dietary WC did not affect dry matter intake, milk yield or milk concentrations of fat, protein or lactose. Milk polyunsaturated FA concentrations (total n‐3, total n‐6, LA and ALNA) and transfer efficiency of LA and ALNA were increased with increasing dietary WC supply.

CONCLUSION

Inclusion of WC in pastures may increase concentrations of nutritionally beneficial FA, without influencing milk yield and basic composition, but any implications on human health cannot be drawn. © 2018 The Authors. Journal of the Science of Food and Agriculture published by JohnWiley & Sons Ltd on behalf of Society of Chemical Industry.

     

Concentration‐dependent antioxidant activities of conjugated linoleic acid and α‐tocopherol in corn oil

BACKGROUND: Antioxidants prevent rancidity (lipid peroxidation) and natural antioxidants, e.g., α‐tocopherol, likely provide additional value to oil‐based food products because of their health benefits. Conjugated linoleic acid (CLA) has potential health benefits and may exhibit antioxidant properties. The main aim of this study was to compare the antioxidant efficacy of α‐tocopherol, trans‐10, cis‐12‐CLA and cis‐9, trans‐11‐CLA (in graded concentrations) added to antioxidant‐stripped corn oil. RESULTS: As compared to α‐tocopherol, both CLA isomers displayed significant inhibition of corn oil lipid peroxidation induced by copper. Inhibition of thiobarbituric acid reactive substances (TBARS) were CLA concentration dependent for both isomers but with significant inhibition occurring at 0.1 and 1 ppm of CLA isomers or α‐tocopherol, respectively (P < 0.05). Graded concentrations of α‐tocopherol, and for both CLA isomers and time, had significant effects on TBARS formation (P < 0.0001). There were significant effects in interactions between graded concentrations and time for both CLA isomers (P < 0.0001) but not for α‐tocopherol (P > 0.05). CONCLUSION: CLA compounds could serve as useful food antioxidants and provide additional value because of their potential bioactivity in disease prevention. Copyright © 2007 Society of Chemical Industry     

Total and organic mercury,selenium and α‐tocopherol in some deep‐water fish species

BACKGROUND: Mercury is a well‐known toxic element present in seafood. Nevertheless some antioxidants, like selenium, as an integral component of the enzyme glutathione peroxidase, and α‐tocopherol having a protective role against it, are present as well. The purpose of this study was to evaluate the levels of total mercury (Hg_T), organic mercury (Hg_Org), Se and α‐tocopherol in some adult deep‐water fish species caught off Portuguese waters. RESULTS: Levels of Hg_T were above EU limits in 6% of Lophius spp. and Aphanopus carbo, 2% of Lepidorhombus spp. and 70% of Helicolenus dactylopterus. Hg_Org represented the major fraction (more than 84%) of Hg_T in all studied muscles. The selenium concentration in muscle was similar in all species (about 0.4 mg kg^?1 wet weight) and the highest level of α‐tocopherol (70 mg kg^?1 wet weight) was found in Aphanopus carbo. CONCLUSION: The muscle of all species studied is a good source of selenium, but only can give a small contribution of α‐tocopherol. Attending to the provisional tolerable weekly intake established by the WHO/FAO for methylmercury, it appears that the species studied should be consumed sparingly. Copyright © 2008 Society of Chemical Industry     

Supplementary α‐tocopherol acetate in full‐fat rapeseed‐based diets for pigs: effect on performance,plasma enzymes and meat drip loss

Twenty‐four Large White × Landrace pigs were individually fed, from 50 to 90 kg live weight, either a control (CONT) diet containing palm oil or one of three diets based on full‐fat rapeseed (250 g kg⁻¹) (diets RD). The RD diets were supplemented with 0, 200 or 500 mg DL ‐α‐tocopherol acetate (ATA) kg⁻¹ diet (diets RD0, RD200 and RD500 respectively). Diets were formulated to be isonitrogenous and isocaloric. Daily live weight gain was significantly increased (p < 0.01) in pigs fed diet RD500. Plasma AT concentration was significantly increased by dietary supplementation with 200 mg ATA kg⁻¹ but showed no further significant increase by supplementation with 500 mg ATA kg⁻¹. At slaughter, after 45 days, carcass weights were increased for the RD500 group but dressing percentage was unaffected. ATA supplementation significantly reduced drip loss on days 4 and 5–7 in fresh muscle and on days 1 and 4 in frozen muscle. The concentrations of calcium, sodium and potassium in drip loss fluid collected on days 1 and 4 from fresh muscle were not significantly affected by treatment or by time of collection and did not suggest any change in the relative contribution of intra‐ and extracellular fluid to total drip loss. Plasma enzyme activities related to tissue damage (creatine kinase, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase) were not influenced by dietary treatments. © 2000 Society of Chemical Industry     

Starch but not protein digestibility is altered in pigs fed transgenic peas containing α‐amylase inhibitor

Eighteen individually housed boars were randomly allocated to one of three dietary treatments, an experimental wheat diet containing 989.4 g kg^?1 of a basal wheat diet, or this experimental wheat diet with 500 g kg^?1 of the basal wheat diet replaced with 500 g kg^?1 of either transgenic or non‐transgenic peas. The transgenic peas expressed the bean (Phaseolus vulgaris L.) α‐amylase inhibitor 1 gene. Diets contained n‐hexatriacontane (0.2 g kg^?1) as an indigestible marker to allow the determination of nutrient digestibility at the terminal ileum. Pigs were offered 1.6 kg day^?1 for 15 days, after which they were anaesthetised, the ileal and faecal digesta collected and the pigs subsequently euthanased. The ileal dry matter and starch digestibilities of the experimental wheat, non‐transgenic and transgenic pea diets were 78.3, 74.2 and 45.8% and 95.9, 95.2 and 42.4%, respectively. The apparent nutrient digestibilities of the non‐transgenic and transgenic peas were determined by difference. The ileal dry matter digestibility was significantly reduced in the transgenic peas compared with the non‐transgenic peas (12.7 and 69.9%, respectively; P = 0.006), which was largely due to a reduced starch digestibility. The apparent crude protein digestibilities of the transgenic peas were similar to the non‐transgenic, being 79.7 and 78.5%, respectively. The amino acid digestibilities of the transgenic and non‐transgenic peas were also similar. Copyright © 2006 Society of Chemical Industry