Biomedical subjects

P A Morrissey

Publications and source records attributed to P A Morrissey.

At least 19 recordsLinked to original sources

PubMed2001

Low-dose supplementation with lycopene or beta-carotene does not enhance cell-mediated immunity in healthy free-living elderly humans.

OBJECTIVE: To assess the effects of supplementation with the carotenoids, beta-carotene or lycopene, at levels achievable within a diet rich in fruit and vegetables, on immune function in a group of free-living healthy elderly. DESIGN: A double-blind randomized placebo-controlled trial. T cell subsets and the expression of functionally associated cell surface molecules, quantified by flow cytometry, and lectin-stimulated lymphocyte proliferation, were compared before and following the treatment period. SUBJECTS: Fifty-eight subjects aged over 65 y were recruited; 52 were included in the final analysis. INTERVENTIONS: Participants received one placebo, one lycopene (13.3 mg) or one beta-carotene (8.2 mg) capsule daily for 12 weeks. RESULTS: No significant differences were observed in any of the parameters examined following either lycopene or beta-carotene supplementation. CONCLUSIONS: In well-nourished, free-living, healthy elderly individuals, supplementation with relatively low levels of beta-carotene or lycopene is not associated with either a beneficial or detrimental effects on several aspects of cell-mediated immunity.

Aged↗

PubMed2001

Susceptibility of LDL to oxidative modification in healthy volunteers supplemented with low doses of n-3 polyunsaturated fatty acids.

The objective of the present study was to evaluate the oxidative susceptibility of LDL in human volunteers following supplementation with various low doses (<1 g/d) of n-3 polyunsaturated fatty acids (PUFA). Sixty-two healthy volunteers (thirty-seven males and twenty-five females, aged 19-63 years) were recruited to take part in a randomised placebo-controlled trial. Volunteers were required to take 0.9, 0.6 or 0.3 g n-3 PUFA as fish oil or placebo capsules daily for 16 weeks. Susceptibility of LDL to oxidative modification was assessed by measuring the production of conjugated dienes and thiobarbituric acid-reactive substances in LDL oxidised by Cu2+ (15 microM) or 2,2'-azobis(2-amidinopropane) dihydrochloride (1 mM) for 5 h. Plasma fatty acid and LDL-fatty acid composition, cholesterol levels and antioxidant concentrations were also measured. While post-treatment n-3 PUFA compositions of plasma and LDL reflected the capsule contents, no meaningful differences in antioxidant concentrations or cholesterol levels were observed between the groups. Supplementation with low doses of n-3 PUFA as fish oil did not influence the oxidative susceptibility of LDL. The results of the present study suggest that moderate dietary intakes of n-3 PUFA do not significantly influence the susceptibility of LDL to oxidative modification in vitro.

Adult↗

PubMed2001

Macronutrient intakes and food sources in Irish adults: findings of the North/South Ireland Food Consumption Survey.

OBJECTIVE: To describe macronutrient intakes and food sources of the adult population in the Republic of Ireland and Northern Ireland and to assess adherence of this population to current dietary recommendations. DESIGN: A cross-sectional food consumption survey collected food intake data using a 7-day food diary. SETTING: Northern Ireland and the Republic of Ireland between October 1997 and October 1999. SUBJECTS: One thousand three hundred and seventy-nine adults aged 18-64 years (662 males and 717 females). RESULTS: Mean daily energy intakes in men were 11 MJ per day, 15.5% was derived from protein, 34.8% from fat, 43.5% from carbohydrate and 5.9% from alcohol. Corresponding figures for women were 7.6 MJ per day, 15.6%, 35.6%, 45.1% and 3.5%. When alcohol energy was excluded the contribution of fat and carbohydrate to energy did not differ between men and women. When compared with existing dietary recommendations, 93% of men and 86% of women had protein intakes above the Population Reference Intake. Two approaches were used to assess adherence to the fat and carbohydrate dietary recommendations: (1) the proportion of individuals in the population attaining these dietary targets and (2) the proportion of the population that was included in a 'compliers' group which had a group mean equal to these dietary targets. Thirty-three per cent of men and 34% of women met the target of 35% of food energy from fat and 78% of men and 80% of women comprised the 'compliers' group having a group mean of 35% of food energy from fat. Twenty-three per cent of men and 27% of women met the target of 50% of food energy from carbohydrate and 56% of men and 62% of women made up the 'compliers' group. Meat and meat products were the main source of fat (23%) and protein (37%), and bread and rolls (25%) were the main source of carbohydrate. CONCLUSION: A reduction in dietary fat intake remains an important public health issue in the Republic of Ireland and Northern Ireland. An increase in carbohydrate intake and attention to the rise in alcohol intake is also warranted.

Adolescent↗

PubMed2001

Effect of dietary oils and alpha-tocopheryl acetate supplementation on lipid (TBARS) and cholesterol oxidation in cooked pork.

The effect of n-3 fatty acid-enriched diets (in the form of 0.5% linseed oil with either 1.5% sunflower oil or 1.5% olive oil) and alpha-tocopheryl acetate supplementation (200 mg/kg feed) on lipid oxidation (thiobarbituric acid-reactive substances, TBARS) and cholesterol oxide products (COPS) in cooked pork was investigated. Longissimus muscle was studied. Meat from pigs fed 0.5% linseed oil-enriched diets had a higher proportion of n-3 fatty acid than meat from pigs in other dietary groups in neutral (P < 0.0001) and polar lipids (P < 0.0001), and a 20% reduction in the n-6:n-3 ratio was observed. Alpha-tocopheryl acetate supplementation increased (P < 0.05) monounsaturated fatty acids in polar lipids and increased (P = 0.0001) alpha-tocopherol levels in muscle. Alpha-tocopherol concentration in muscle was affected by dietary fat (P < 0.05). Groups receiving diets enriched with sunflower oil had significantly higher alpha-tocopherol levels (P < 0.05) in muscle than those groups receiving olive oil-enriched diets. Numbers of TBARS were significantly (P < 0.05) lower in the group fed supplemental olive oil than in those fed sunflower oil. Dietary linseed oil increased (P < 0.05) lipid oxidation principally at the initial period of storage in cooked pork. Overall, dietary alpha-tocopheryl acetate supplementation significantly increased (P < 0.001) lipid stability and decreased (P < 0.05) total COP production across the dietary groups. Alpha-tocopherol was a more effective antioxidant for decreasing TBARS values in cooked meat when adding sunflower oil to the diets instead of olive oil.

Animals↗

PubMed2001

Nutrition and lifestyle survey of 15-17 year old second level school pupils in the Cork city area.

This study deals with the dietary intakes of a representative sample of Cork city area, school-going children, aged 15-17 years (n=125). Dietary intake was assessed by diet history with published food portion sizes to estimate size. Background data and information on lifestyle were collected by means of a questionnaire. Results indicate that, in general, the study group was reasonably well nourished. However, fat consumption (40%) was higher than the target of <35% for energy intake, for both males and females, and saturated fat intake (15%) was also above the 10% of energy guideline. The percentage of energy derived from carbohydrate (45%) was below the guideline value of 50% for energy intake for males and females. Relatively low iron, calcium and folate intakes were found for females. Smoking was more prevalent among females than males. Alcohol consumption among females was higher than among males. Even though all students participated in some physical activity, less females participated in high activity sport. Based on these results, some concern about the dietary habits and the related health consequences in Cork adolescents appears justified.

Adolescent↗

PubMed2000

Lipoprotein carotenoid profiles and the susceptibility of low density lipoprotein to oxidative modification in healthy elderly volunteers.

OBJECTIVES: To determine antioxidant levels in plasma, low density lipoprotein (LDL) and high density lipoprotein (HDL) before and after supplementation with a carotene mixture or lycopene; to examine the interrelationships between carotenoids and tocopherols in plasma, LDL and HDL under normal dietary conditions and after supplementation with carotene or lycopene; and to investigate whether supplementation with a carotene mixture or lycopene could enhance the ability of LDL to withstand oxidative stress in vitro, in a group of healthy elderly people aged > or =65 y. DESIGN: Randomized placebo controlled double blind study. SETTING: Free living urban adults in Ireland. SUBJECTS: Fifty-one volunteers aged > or =65 y. INTERVENTIONS: Volunteers were each provided with capsules providing either 13.3 mg lycopene, or 11.9 mg carotene or placebo for 12 weeks. RESULTS: Both absolute and cholesterol standardized plasma carotenoid concentrations correlated strongly with LDL and HDL concentrations of carotenoids before and after supplementation with carotene or lycopene. Supplementation with a carotene mixture or lycopene had no effect on oxidative modification of LDL in vitro despite significant increases in plasma and LDL concentrations of lycopene, alpha-carotene and beta-carotene. CONCLUSIONS: The results of this study suggest that, in unsupplemented individuals, plasma can act as a biomarker of carotenoid and gamma-tocopherol concentrations in both LDL and HDL. Supplementation with carotenes or lycopene do not reduce or delay oxidation of LDL. These results support the assumption that carotenoids, such as beta-carotene and lycopene, may show protective effects because they are good markers of fruit and vegetable intake.

Aged↗

PubMed1999

Optimal nutrition: vitamin E.

Interest in the role of vitamin E in disease prevention has encouraged the search for reliable indices of vitamin E status. Most studies in human subjects make use of static markers, usually alpha-tocopherol concentrations in plasma or serum. Plasma or serum alpha-tocopherol concentrations of < 11.6, 11.6-16.2, and > 16.2 mumol/l are normally regarded as indicating deficient, low and acceptable vitamin E status respectively, although more recently it has been suggested that the optimal plasma alpha-tocopherol concentration for protection against cardiovascular disease and cancer is > 30 mumol/l at common plasma lipid concentrations in combination with plasma vitamin C concentrations of > 50 mumol/l and > 0.4 mumol beta-carotene/l. Assessment of vitamin E status has also been based on alpha-tocopherol concentrations in erythrocytes, lymphocytes, platelets, lipoproteins, adipose tissue, buccal mucosal cells and LDL, and on alpha-tocopherol: gamma-tocopherol in serum or plasma. Erythrocyte susceptibility to haemolysis or lipid oxidation, breath hydrocarbon exhalation, oxidative resistance of LDL, and alpha-tocopheryl quinone concentrations in cerebrospinal fluid have been used as functional markers of vitamin E status. However, many of these tests tend to be non-specific and poorly standardized. The recognition that vitamin E has important roles in platelet, vascular and immune function in addition to its antioxidant properties may lead to the identification of more specific biomarkers of vitamin E status.

Ascorbic Acid↗

PubMed1999

Relationship between smoking, dietary intakes and plasma levels of vitamin E and beta-carotene in matched maternal-cord pairs.

The concentrations of tocopherols and carotenoids are lowered in umbilical cord blood plasma, which may have a negative effect on antioxidant protection in neonates. Smoking may adversely affect dietary intakes and plasma concentrations of carotenoids. The dietary intakes of vitamin E and beta-carotene were assessed in 66 pregnant women (31 smokers and 35 non-smokers) between 10 and 20 weeks gestation using a food frequency questionnaire. The concentrations of alpha-tocopherol and beta-carotene were measured in maternal plasma at the time of the dietary assessment, and in the matched umbilical cords of their newborn after delivery. In smoking and non-smoking mothers, the mean intakes of vitamin E (9.3 [SD 5] and 8.2 [SD 5] mgd-1) and beta-carotene (3464 [SD 1885] and 2977 [SD 1503] micrograms d-1) were not significantly different. The plasma concentrations of alpha-tocopherol (20.8 [SD 4] and 20.5 [SD 4] mumol L-1), the alpha-tocopherol to lipid ratios (3.2 [SD 0.8] and 3.5 [SD 0.8]) and the plasma concentrations of beta-carotene (0.22 [SD 0.1] and 0.22 [SD 0.1] mumol L-1) were not significantly different in smoking and non-smoking mothers. There were no significant differences in plasma alpha-tocopherol (7.4 [SD 2] and 7.3 [SD 2] mumol L-1), in alpha-tocopherol to lipid ratios (3.2 [SD 0.6] and 2.8 [SD 0.6]) or in beta-carotene concentrations (0.05 [SD 0.04] and 0.03 [SD 0.02] mumol L-1) in cords from newborns of smoking and non-smoking mothers. There was a significant correlation (r = 0.41, P = 0.015) between dietary intakes and plasma concentrations of beta-carotene in non-smoking mothers. However, this relationship was not significant in smoking mothers (r = 0.28, P = 0.12). There were no relationships between dietary intakes and plasma concentrations of tocopherol. These results indicate that smoking during pregnancy does not appear to affect the dietary intakes or plasma concentrations of alpha-tocopherol and beta-carotene in pregnant women or their babies. However, smoking does influence the relationship between dietary intakes and plasma levels of beta-carotene.

Adolescent↗

PubMed1999

Carotenoids in young and elderly healthy humans: dietary intakes, biochemical status and diet-plasma relationships.

OBJECTIVE: To determine dietary carotenoid concentrations using an established and newly developed food frequency questionnaire (FFQ) method, to determine plasma carotenoid concentrations and to determine the relationship between these dietary and plasma variables in 24-45 y and > or = 65 y groups. DESIGN: Descriptive assessment of (FFQ), 7-d estimated records, and plasma carotenoids and their relationships in 24-45 y and > or = 65 y groups. SETTING: Free living urban adults in Ireland. SUBJECTS: Sixty-four volunteers aged 24-45 y and 54 volunteers aged > or = 65 y. RESULTS: Beta-carotene was the predominant plasma carotenoid, but older groups had lower plasma concentrations of several carotenoids compared to younger groups (P < 0.005). Beta-carotene and lycopene were the major dietary carotenoids reported by estimated records and FFQ. Several estimated record and plasma carotenoid concentrations were positively associated in younger groups but not in older groups. FFQ overestimated dietary carotenoids relative to estimated records (P < or = 0.05), generally did not reflect estimated record carotenoid concentrations and showed positive associations with plasma carotenoids only in older men. Neither of the dietary methods revealed a positive association between plasma and dietary beta-carotene concentrations, whereas beta-cryptoxanthin was strongly associated. CONCLUSIONS: Dietary and plasma concentrations of individual carotenoids are documented in young and elderly groups of a European country. Estimated record data reveals positive associations between diet and plasma carotenoids in younger, but not elderly groups. Further work examining diet-plasma relationship in older groups and developing a common FFQ suitable for use in several European countries is required.

Adult↗

PubMed1999

Concentrations of tocopherols and carotenoids in maternal and cord blood plasma.

OBJECTIVES: To determine the levels of tocopherols, retinol and carotenoids in maternal and umbilical cord blood plasma and to investigate the relationships between them. DESIGN: Venous blood plasma concentrations of alpha, gamma and delta-tocopherol, retinol, lutein, lycopene, zeaxanthin, beta-cryptoxanthin, alpha and beta-carotene were determined by HPLC in healthy pregnant women and in pair-matched umbilical cords. Plasma levels of triglycerides and cholesterol were also measured. SUBJECTS: Sixty-six women, between 10 and 20 weeks gestation, were recruited randomly during their first antenatal appointment. From this group, 40 pair-matched umbilical cord blood samples were obtained. RESULTS: Tocopherols, retinol, carotenoids and lipids were present in significantly higher (P < 0.001) concentrations in maternal plasma than in cord plasma. There was a significant correlation (r = 0.45, P < 0.005) between maternal and cord levels of gamma-tocopherol, but not of alpha-tocopherol, retinol or carotenoids. Tocopherols and carotenoids were significantly correlated with each other (P < 0.05) in maternal and cord plasma. CONCLUSIONS: Plasma levels of tocopherols, carotenoids and lipids are substantially lower at birth than in adulthood. There is a clear relationship between gamma-tocopherol levels in maternal and cord plasma. The importance of gamma-tocopherol in human nutrition should be further investigated. There are no significant relationships between plasma alpha-tocopherol and carotenoids in pregnant mothers and cords. More research is needed to elucidate the maternal-foetal transfer of tocopherols and carotenoids, and to examine the impact of maternal antioxidant nutrient status on neonatal antioxidant capacity. It is important to determine if a low level of tocopherols and carotenoids at birth is a normal stage of human development or indicative of deficiency.

Adolescent↗

PubMed1999

Low molecular weight plasma antioxidants and lipid peroxidation in maternal and cord blood.

OBJECTIVE: To determine the concentrations of the low molecular weight antioxidants urate, bilirubin, albumin and sulphydryl groups and to measure lipid peroxidation levels in pair-matched maternal and cord blood plasma. DESIGN: Venous blood plasma concentrations of urate, bilirubin, albumin and sulphydryls were determined in healthy pregnant women and in pair matched umbilical cords. The ability of maternal and cord plasma to withstand Cu2+-induced lipid peroxidation was assessed by measuring the production of thiobarbituric acid reactive substances (TBARS) over time in plasma incubated with Cu2+. SUBJECTS: Forty healthy women, between 10 and 20 weeks gestation, were recruited randomly from an antenatal clinic. Venous blood samples were obtained from the mothers at the recruitment stage and from the umbilical cords of their newborn after delivery. RESULTS: Urate, bilirubin and sulphydryls were present in significantly higher concentrations (P<0.001) in cord plasma than in maternal plasma. Albumin levels were similar in mothers and cords. Significantly lower levels (P=0.018) of TBARS were produced in cord plasma compared with maternal plasma following incubation with Cu2+. There were significant correlations between albumin and sulphydryl concentrations in maternal plasma (r 0.43, P=0.007) and between urate concentrations in maternal and cord plasma (r 0.37, P=0.026). CONCLUSION: Urate, bilirubin and sulphydryls are present in significantly higher concentrations in cord blood than in maternal blood. The increased levels of these antioxidants in cord plasma may contribute to the increased resistance of cord plasma to Cu2+-induced lipid peroxidation.

Adolescent↗

PubMed1999

Effects of alpha-tocopheryl acetate supplementation and salt addition on the oxidative stability (TBARS) and warmed-over flavour (WOF) of cooked turkey meat.

1. Day-old turkey poults (n = 14) were randomly divided into 2 groups (n = 7) and fed diets containing 20 (E20) and 600 (E600) mg all-rac-alpha-tocopheryl acetate/kg food for 21 weeks prior to slaughter. Following slaughter, breast and leg meat was removed and 4 batches of patties were produced from each. Two of the batches were formed from E20 meat (E20) and E20 plus 1% salt (E20S). Two similar batches were formed from E600 meat (E600) and E600 plus 1% salt (E600S). 2. Patties were fried, cooled and overwrapped with high oxygen-permeable film. Overwrapped patties were displayed in a 4 microC cabinet under fluorescent light (616 lux). Lipid oxidation (TBARS numbers) was determined on d 0, 2, 4, 6, 8 and 10, while taste panels to assess warmed-over flavour (WOF) were carried out on d 0, 2 and 4 of refrigerated (4 degrees C) display. 3. In the case of both leg and breast meat, E600 patties were the least susceptible of the 4 treatment batches to lipid oxidation. Salt had the effect of promoting lipid oxidation, with E20S and E600S patties having higher TBARS numbers than the corresponding patty batches where salt was absent. 4. Taste panel results showed that leg and breast patties formed from the meat of turkeys given alpha-tocopheryl acetate enriched diets developed significantly (P < 0.05) less WOF than those formed from control turkey meat on d 2 and 4 of refrigerated (4 degrees C) display. Patties containing 1% salt generally exhibited a greater degree of WOF than patties without salt. 5. A linear relationship was observed between TBARS numbers and WOF percentages for all batches of leg and breast patties.

Animal Feed↗

PubMed1998

Assessment of alpha-tocopheryl acetate supplementation, addition of salt and packaging on the oxidative stability of raw turkey meat.

1. One-day-old turkey poults (n = 14) were randomised into 2 groups (n = 7) and fed diets containing 20 (E20) and 600 (E600) mg all-rac-alpha-tocopheryl acetate/kg food for 21 weeks prior to slaughter. Two batches were formed from E20 meat (E20) and E20 plus 10 g salt/kg (E20S). Two similar batches were formed from E600 meat (E600) and E600 plus 10 g salt/kg (E600S). 2. The effects of alpha-tocopheryl acetate supplementation and salt addition on the oxidative stability of raw turkey patties was investigated during aerobic and vacuum-packaged refrigerated (4 degrees C) storage. 3. Dietary alpha-tocopheryl acetate supplementation reduced TBARS (thiobarbituric acid reacting substances) numbers for raw overwrapped and vacuum-packaged turkey leg and breast patties. 4. Dietary alpha-tocopheryl acetate had the greatest influence on TBARS numbers for raw overwrapped turkey leg patties. 5. The addition of 10 g salt/kg increased TBARS numbers for overwrapped and vacuum-packaged turkey leg and breast patties. 6. Vacuum-packaged patties remained more oxidatively stable than similarly treated overwrapped patties throughout the experimental period.

Analysis of Variance↗

PubMed1998

Comparison of effects of dietary olive oil, tallow and vitamin E on the quality of broiler meat and meat products.

1. The effect of dietary fat and vitamin E supplementation on quality attributes (drip loss, oxidative stability, sensory quality) in chicken meat and meat products was investigated. Broiler chicks were fed on diets containing tallow (60 g/kg) or olive oil (60 g/kg) at a basal (30 mg/kg diet) or supplemental (200 mg/kg diet) concentration of alpha-tocopheryl acetate for 8 weeks. The alpha-tocopherol content and fatty acid composition of breast and thigh meat was determined. Drip loss was determined in breast fillets. Lipid oxidation (thiobarbituric acid-reacting substances/TBARS) and sensory quality (warmed-over flavour development/WOF) were assessed in minced thigh meat during storage. 2. Dietary olive oil increased the ratio of monounsaturated to saturated fatty acids (MUFA/SFA) in the diets. In breast and thigh, this resulted in approximately a two-fold increase in the MUFA/SFA ratio. Supplemental alpha-tocopherol increased the alpha-tocopherol content of muscles. 3. Dietary fat not influence drip loss in thawed breast fillets during refrigerated storage, but supplemental alpha-tocopherol reduced drip loss. 4. TBARS and WOF development in minced thigh meat patties were also reduced by supplemental alpha-tocopherol following frozen storage, or cooking and refrigerated storage. Storage stability was not adversely affected by dietary fat. 5. Overall, the results showed that increasing the monounsaturated profile of chicken meat lipids did not adversely affect quality characteristics. Dietary alpha-tocopherol supplementation was a more important factor in the determination of broiler meat quality.

Analysis of Variance↗

PubMed1998

Effect of myofibrillar muscle proteins on the in vitro bioavailability of non-haem iron.

It is well established that the bioavailability of non-haem iron from foods is enhanced by the presence of meat. However, the nature of the promoter in meat has not yet been characterised. The present study was designed to compare the effects of the myofibrillar protein fractions on the bioavailability of non-haem iron in an attempt to identify the 'meat factor'. Rabbit skeletal muscle was fractionated and whole muscle, myofibrillar protein, myosin and actin were isolated. Myosin was subjected to selective proteolysis with chymotrypsin and the heavy meromyosin, light meromyosin, rod region and head region were prepared. Protein fractions (1 g) were incorporated into 100 g semi-synthetic liquid meal and the in vitro dialysability of iron was determined. Egg albumin was used as a reference protein. When compared with egg albumin, all protein fractions significantly enhanced iron dialysability, except for light meromyosin which was inhibitory. Myosin had a greater enhancing effect than actin and, within myosin, the enhancing effect was greatest for the heavy meromyosin fraction. The enhancement appeared to coincide with the known distribution of cysteine residues in the myofibrillar proteins. The presence of the sulphydryl blocking agent, N-ethylmaleimide (NEM), in meals containing myosin reduced iron dialysability in a dose-related manner, but NEM had only a small effect in meals containing actin. Meanwhile, incorporation of cysteine into meals containing actin increased iron dialysability. The present results suggest that the enhancement of non-haem iron dialysability by meat is associated with myosin, in particular, with the heavy meromyosin region. Peptide fractions rich in cysteine residues, probably constitutes the 'meat factor'.

Actins↗

PubMed1997

Tissue content of alpha-tocopherol and oxidative stability of broilers receiving dietary alpha-tocopheryl acetate supplement for various periods pre-slaughter.

1. The effects of dietary alpha-tocopheryl acetate on the alpha-tocopherol status of chicken plasma and tissues were investigated. The rate of iron-ascorbate-induced lipid peroxidation was also studied. 2. One hundred and forty four chicks were divided into 6 groups: one control group was fed a basal diet of 30 mg alpha-tocopheryl acetate/kg food for the duration of the trial. A supplemental diet of 200 mg alpha-tocopheryl acetate was fed to each of the other 5 groups for 1,2,3,4 or 5 weeks prior to slaughter. 3. Supplementation resulted in an increase in alpha-tocopherol in plasma and all tissues examined. Saturation levels of alpha-tocopherol were observed in plasma after 1 week of feeding and in tissues within 3 to 4 weeks of feeding. 4. Supplementation with alpha-tocopheryl acetate for up to 4 weeks pre-slaughter resulted in significant reductions in susceptibility to induced lipid peroxidation. 5. Overall, the results show that feeding 200 mg alpha-tocopheryl acetate/kg food to chicks for at least 4 weeks prior to slaughter is necessary to optimise muscle content and stability against lipid peroxidation.

Abattoirs↗

PubMed1997

Influence of dietary vitamin E and oxidised sunflower oil on the storage stability of cooked chicken muscle.

1. The effects of oxidised dietary sunflower oil and dietary alpha-tocopheryl acetate supplementation on alpha-tocopherol concentrations in broiler muscle and on the storage stability of refrigerated, cooked, minced muscle were determined. Broiler chicks were fed on diets containing fresh sunflower oil and 30 (FS30) or 200 (FS200) mg alpha-tocopheryl acetate/kg, or oxidised sunflower oil and 0 (OS0), 30 (OS30) or 200 (OS200) mg alpha-tocopheryl acetate/kg. 2. Inclusion of oxidised sunflower oil significantly reduced dietary and hence, muscle alpha-tocopherol concentrations. 3. Oxidised oil increased oxidation in raw and cooked muscle, and reduced the oxidative stability of muscle during refrigerated and frozen storage. 4. Supplementation with alpha-tocopheryl acetate improved the stability of muscle, with stability increasing as muscle alpha-tocopherol concentrations increased, when fresh or oxidised oil was fed. Supplementation with 200 mg alpha-tocopheryl acetate/kg offset the effects of oxidised oil in breast, but not in thigh. 5. The results show that the prooxidising effects of oxidised oils in muscle foods can be overcome, but alpha-tocopherol content needs to be adequately adjusted to compensate for increased oxidative stress. Supplementation with 200 to 400 mg alpha-tocopheryl acetate/kg may be necessary to achieve an optimum muscle alpha-tocopherol concentration.

Animals↗

PubMed1996

Oxidative stability and alpha-tocopherol retention in turkey burgers during refrigerated and frozen storage as influenced by dietary alpha-tocopheryl acetate.

1. The effect of vitamin E (alpha-tocopheryl acetate) in turkey diets on the oxidative stability of raw and cooked turkey burgers and on the retention of alpha-tocopherol during refrigerated (4 degrees C) or frozen (-20 degrees C) storage was investigated. One hundred and two, one-day-old T-8s turkey poults were divided at random into 3 groups of 34 animals each and fed on either a basal diet (normal commercial turkey diet) supplemented with 20 mg alpha-tocopheryl acetate/kg (control) or fed an alpha-tocopherol supplemented diet containing 300 (E300) or 600 (E600) mg alpha-tocopheryl acetate/kg for 21 weeks. 2. Dietary supplementation with alpha-tocopheryl acetate significantly reduced TBARS numbers in both raw and cooked burgers during refrigerated and frozen storage. 3. The mean values of alpha-tocopherol in raw and cooked burgers stored at 4 degrees C did not change during storage. 4. In the case of both raw and cooked samples stored at -20 degrees C, the alpha-tocopherol values decreased from 5.67 to 3.54 and from 3.56 to 2.30 micrograms/g in the raw burgers from turkeys from the E600 and E300 treatments, respectively, after 4 months storage. The values decreased from 5.60 to 2.88 and from 3.29 to 1.85 micrograms/g in cooked burgers from turkeys from the E600 and E300 treatments, respectively, after 5 months storage.

Animals↗