Refrigeration Period Research Articles

Importance of refrigeration time in the electrospinning of silk fibroin aqueous solutions

Refrigeration is a common method for preserving reconstituted silk fibroin (RSF) aqueous solutions during electrospinning experiments, but the effects of preservation time at 4 °C are still not well documented. In this work, we explore its effects on the viscosity, refractive index, and density values of RSF solutions at 19 wt%. Also, extensive characterization of the mechanical properties and fiber diameters of the resulting electrospun meshes are provided. Significant differences were found in elongation, Young´s modulus, and ultimate strength at different experimental times, and an increase in the viscosity values of the RSF solutions was detected for the first 12 days of storage. These solutions exhibited a continuous, slow gelation throughout the time in storage at 4 °C, and this phenomenon improved the performance of electrospinning after a certain period of refrigeration. The protocol used reduces the production cost of SF fiber-based scaffolds and avoids the use of harsh solvents and additives which could otherwise limit their use in potential biomedical applications.

The effects of three extenders on refrigerated boar semen

This study aims to evaluate the quality of boar sperm that was refrigerated for 14 days at 17 ºC with three extenders. For this study, samples from four boars were collected twice a week using the gloved-hand technique. After collection, only ejaculates showing total motility of 75% or greater were submitted to the refrigeration process. Ejaculates were diluted in Androhep, MR-A® or Reading. Each portion was kept for two hours at 22 ºC, then sperm motility was assessed through contrast microscopy. Sperm mitochondrial activity, viability and acrosome integrity were measured by the flow cytometric technique. The remaining diluted semen was maintained at 17 ºC for 336 h, and the same analysis being repeated every 48 h. Semen diluted in Androhep revealed no significant quality deterioration in percentage of live spermatozoa during refrigeration. However, after 144 h, viability decreased significantly for MR-A® and Reading (63.3% ± 7.0 and 66.4% ± 6.2, respectively), and after 336 h, this decrease was accentuated (56.3% ± 3.9 and 18.4% ± 6.2, respectively, for MR-A® and Reading). On average, for all three extenders, acrosome integrity values did not differ statistically up to 144 h, ranging from 48.3 ± 2.3 for MR-A® to 62.4 ± 3.2 for Androhep. Then values decreased towards the end of the experiment, with Androhep always presented the higher values, while Reading resulted in the lowest values (46.3 ± 3.2 and 5.6 ± 1.4, respectively). No significant changes in mitochondrial membrane potential were observed during the refrigeration period. Results of this study indicate that Androhep achieves the best results for the various parameters studied over time.Keywords: Boar, flow cytometry, long-term extenders, refrigeration, semen

Analysis of Some Phenolic Compounds and Free Radical Scavenging Activity of Strawberry Fruits During Storage Period

Abstract The objective of this study was to evaluate the quantity of some phenolic compounds and free radical scavenging activity of strawberries (Fragaria x ananassa Duch.) during storage period at different temperatures. Freshly harvested of three strawberry cultivars fruits (‘San Andreas’, ‘Benicia’ and ‘Albion’) were placed in polyethylene bags and kept in refrigerated (4 °C) and frozen (-85 °C) conditions for 7 days. Therefore, the analyses performed were applied on the fruits in stages: fresh, refrigerated and frozen. With regard to the bio compounds analysis, we mention: total phenolic content (TPC) expressed as g gallic acid equivalents (GAE), total flavonoid content (TFC) expressed as g of rutin equivalents (RE), and free radical scavenging activity expressed as 50% effective concentration (EC50) (mg/ml). With regard to the TPC in all analyzed storage stages have revealed ‘San Andreas’ cultivar with a maximum content of 0.326 g GAE / 100 g fresh weight (FW). Also, the same cultivar recorded high levels of total flavonoid content of 0.424 g RE / 100 g FW, all at the end of refrigeration period. In terms of free radical scavenging activity, ‘Benicia’ cultivar highlighted the best results EC50 = 3.094 mg/ml.

Stabilization of refrigerated avocado pulp: Effect of Allium and Brassica extracts on enzymatic browning

The aim of this paper was to study the effectiveness of Allium and Brassica extracts to inhibit the evolution of enzymatic browning of avocado pulp tissue stored at refrigeration temperature (4 °C). Color parameters and mathematical modeling were employed to determine browning kinetics. In general, the addition of Allium extracts to avocado pulp was more effective in delaying luminosity decrease during the first days of storage, compared to Brassica. Scallion, onion, white cabbage and cauliflower inhibited polyphenol oxidase (PPO), and avocado paste, could be preserved for more than 30 days. Brussels sprouts treatment generated the highest browning kinetic constant (0.86) and conserved acceptable color for less than 10 days. Scallion and garlic showed the great antibrowning indexes (0.96 and 0.77 respectively) considering L* decrease. Multivariate analysis indicated that vegetable extracts tested could be grouped by variety according to polyphenol content, and by their influence on PPO activity. The results allow the conclusion that polyphenol content of vegetables extracts influence the change of color variables during the first days of storage, while PPO activity influence these parameters in the last period of refrigeration.

Características da carcaça e dos componentes não carcaça de cordeiros oriundos de parto simples ou duplo

Um experimento foi conduzido com o objetivo de avaliar as características da carcaça e dos componentes não carcaça de cordeiros nascidos de parto simples ou duplo. Dezesseis cordeiros mestiços Texel × Ile de France, machos não castrados, foram desmamados aos 56 dias de idade e abatidos com aproximadamente 28kg de peso corporal. Imediatamente após o abate, cada componente corporal foi pesado separadamente, sendo as carcaças avaliadas após 24 horas de refrigeração a 2°C. Os cordeiros oriundos de parto simples apresentaram superioridade no peso e nos rendimentos da carcaça, além de maior área de olho de lombo. Por outro lado, proporcionalmente ao peso de corpo vazio, o rúmen é maior em cordeiros nascidos de parto duplo, o que resulta incremento da proporção de conteúdo gastrintestinal ao abate. Os resultados deste estudo indicam que, quando abatidos a um mesmo peso, cordeiros oriundos de parto simples possuem carcaças de melhor qualidade, em comparação a cordeiros nascidos de parto gemelar.

Sperm fertility and viability following 48 h of refrigeration: Evaluation of different extenders for the preservation of bull semen in liquid state

Two experiments were conducted to compare the effectiveness of different extenders conventionally used for semen cryopreservation to maintain the viability and fertility of cooled bull semen. In Experiment 1, sperm samples obtained from 20 Nellore bulls were preserved at 5°C for 48h using two extenders containing 20% of egg yolk [Tris (TRIS-R) and Botu-Bov® (BB)] and another composed of 1% soy lecithin [Botu-Bov®-Lecithin (BB-L)] as substitutes for animal origin products. The samples were evaluated at 6, 24 and 48h for plasma and acrosomal membrane integrity, quantification of thiobarbituric acid reactive substances (ng of TBARS/108 cells) and sperm motility parameters by computer-assisted semen analysis (CASA). In Experiment 2, pregnancy rate (P/AI) of 973 fixed-time artificially inseminated Nellore cows were compared when cows were inseminated with conventionally cryopreserved semen in TRIS-egg yolk glycerol (TRIS-C Control, n=253) or semen cooled for 48h in TRIS-R (n=233), BB (n=247) or BB-L (n=240). Although none of the extenders used was effective on maintaining total progressive motility and cellular integrity throughout the 48-h of the refrigeration period (P<0.01), BB-L conferred greater protection against oxidative stress (P<0.05) than egg yolk-based medias. The P/AI for semen samples preserved in TRIS-C, TRIS-R, BB and BB-L were 39.92a, 25.32b, 26.32b and 33.33ab, respectively. These results demonstrate that the three conventional extenders used for semen cryopreservation do not provide the protection required to maintain bull semen fertility under refrigeration for a 48-h period, resulting in reduced pregnancy rates. However, the use of lecithin-based medium instead of egg yolk results in greater protection against lipid peroxidation, producing P/AI results comparable to those obtained using frozen semen.

A preliminary study into the use of ‘heat pipes’ to prevent high rigor temperature in beef carcasses by increasing cooling rate

Three experiments were conducted to investigate the use of a custom-made heat pipe to reduce muscle temperature in beef carcasses during the initial part of the refrigeration period post slaughter. The effects of muscle depth (Experiment 1) and radial distance from a heat pipe (Experiment 2) were investigated initially. Then the use of multiple heat pipes was compared with no heat pipes for the loin and hind leg regions of a carcass (Experiment 3). All three experiments were conducted at a commercial beef abattoir in Western Australia. Without heat pipes, the time taken for the temperature to fall to 35°C in the hind leg was 10, 90 and 300 min for depths of 25, 50 and 100 mm from the surface, respectively. Temperature increased with radial distance from a heat pipe and the relative differences in temperature between different positions increased with time. Temperatures 110 min after the commencement of cooling were 35.7, 36.8 and 38.3°C for 20, 40 and 80 mm from the heat pipe, compared with 39.8°C without the pipe. The loin cooled faster than the rump, which cooled faster than the leg. Heat pipes increased the rate of temperature loss in the leg but not the loin. The time taken for the leg temperature to reach 35°C, measured at a depth of 100 mm, reduced from 150 to 76 min. These experiments confirm that heat pipes containing methanol could be used to increase the rate of heat loss from leg muscles in beef carcasses. Further work is required to determine if the magnitude of these increases in cooling rate would improve eating quality for large carcasses.

English

An experiment was conducted during the year 2010 to evaluate the effect of the treatment with 1-methylcyclopropene (1-MCP) on the ripening process of sapodilla fruits, after refrigeration. The fruits were exposed to 0 and 1 &micro;L/L of 1-MCP for 24 h in airtight chambers at 25&deg;C, after which they were stored at 16&deg;C for four periods of refrigeration (0, 11, 18 and 25 days). At the end of each refrigeration period, the samples were allowed to ripe at 25&deg;C. The results demonstrated the effectiveness of 1-MCP in significantly delaying (P&le;0.05) the ripening process of sapodilla fruits and extending the post-harvest life to 28 days. It was possible to observe a reduction and delay in the climacteric maximums of ethylene and respiration, and a delay in the maximum activity of the pectin methyl esterase enzyme (PME), while weight loss was also reduced. In general, the quality characteristics of ripe fruits were maintained, except for a significant increase in the total soluble solids content of the fruits treated. These results indicate that the treatment with 1-MCP, combined with refrigeration, is an adequate alternative for increasing the shelf life of sapodilla with the aim of facilitating its commercialization. Key words: Sapodilla, 1-methylcyclopropene, ripening, post-harvest, shelf life, refrigeration.

Babesia: impact of cold storage on the survival and the viability of parasites in blood bags

Babesia represents one of the major infectious threats to the blood supply since clinically silent infections in humans are common and these can be life-threatening in certain recipients. It is important to understand the effect of blood storage conditions on the viability of Babesia as this will impact the occurrence and severity of transfusion-transmitted babesiosis. Babesia divergens was introduced into blood bags containing leukoreduced red blood cells (RBCs) and stored at 4°C for 0 to 31 days. Samples were withdrawn for assessment of the presence, morphology, and viability of parasites. Blood smears were made immediately on removal from blood bags at different time intervals and evaluated by blood film microscopy. RBCs withdrawn from the bags were also cultured for 8 days using conditions optimal for parasite reproduction and growth to allow assessment of parasite viability. After 24 hours of storage at 4°C, there was a substantial reduction of parasitemia in the blood bags, which was maintained throughout storage. This decrease was accompanied by a change in morphology of parasites, with the number of altered parasites increasing through the period of storage. However, viability was maintained through 31 days of cold storage with a lag in achieving exponential growth seen in the parasites subjected to longer periods of refrigeration. Refrigeration of B. divergens leads to an alteration of parasite morphology and a decrease in parasite numbers. However, there are sufficient parasites that are robust enough to survive 31 days of storage at 4°C and yield high end-point parasitemia.

Fatty acid composition and oxidative stability of breast meat from broiler chickens supplemented with Moringa oleifera leaf meal over a period of refrigeration

Effects of diets supplemented with or without Moringa oleifera leaf meal (MOLM) on fatty acid (FA) composition and oxidative stability of broiler breast meat during refrigerated storage was determined. Dietary treatments (T) were as follows: T1, positive control, 668g/ton Salinomycin and 500g/ton Albac; T2, T3 and T4 contained graded levels of MOLM at 1%, 3% and 5% of dry matter (DM) intake, respectively; and T5, a negative control (0% additives). Oxidative stability was evaluated by thiobarbituric acid reactive substances (TBARS) on day (D) 1–8 of storage at 4°C; and FA analysis was done on samples obtained on D1 and D8. Significant effects on TBARS were noted on day (D) 1, 3, 4 and 7; increased with increasing storage time, and with increase in MOLM supplementation. Highest (P<0.05) C18:0 and C15:0 levels were noted on D1 in T2; C20:0 in T4 on D8; C20:2, C20:3n6 and C22:6n3 in T2; C18:3n6 and P/S ratio in T4 on D1; and n-3 in T3. Thus, despite the high SFA content, additive supplementation of M. oleifera leaf meal up to 5% of the bird’s DMI improved the FA profile and reduced lipid oxidation in broiler breast meat.

Sensory profile of warmed-over flavour in tenderloin from steers supplemented with alpha-tocopherol

The objective of the present study was to evaluate the occurrence of warmed-over flavour (WOF) in cooked tenderloin and the influence of alpha-tocopherol on its inhibition. A total of 24 animals were confined, 12 of which received 1200 mg/head/day of alpha-tocopherol acetate for 90 days. Longissimus dorsi muscle cuts (tenderloin) were obtained for sensory profile assessment by nine trained tasters. The tasters evaluated the taste of the meat based on four general and 18 specific attributes. The results of the evaluations were analysed with ANOVA, post-hoc tests of the means (Tukey tests), and principal component analysis (PCA). There was no significant difference in the WOF between the cuts of meat from the supplemented and non-supplemented animals. However, as the refrigeration period increased, there was a decrease in the intensity of the umami and sweet taste attributes and the flavour and aroma of the roast meat as well as an increase in the intensity of the oxidised vegetable oil flavour and the aromas of fish, hard-boiled egg, flaxseed oil, and oxidised vegetable oil. The samples that had been stored for one day were characterised by PCA as having sweet and umami tastes and the flavour and aroma of roast meat, whereas after three days, the samples were classified as having sour and bitter tastes, the flavour of chicken and nuts, and the aroma of fish. The typical sensory attributes desirable for roasted meat decreased in intensity during the three days of storage after cooking, whereas the intensity of unpleasant (oxidative) attributes for the consumer increased.

Molecular and physiological study of postharvest rachis browning of table grape cv Red Globe

Red Globe is one of the most important varieties of table grapes (Vitis vinifera L.) grown for export. Rachis browning is a common problem that affects the quality and marketing of table grape clusters. In general, this process has been associated with water loss, but senescence has also been proposed as additional component in the process. Until now, there has been no evidence clarifying the cellular mechanism underlying this process in rachis. Thus, we conducted a transcriptional analysis using quantitative reverse transcription polymerase chain reaction (qRT-PCR) of 30 putative senescence-associated genes (SAGs). The expression of these genes in rachis was evaluated at harvest and after 90 days at 0°C and under air or controlled atmosphere (CA) conditions. Additionally, the effect of applying cytokinin (Ck) one day before harvest to retard senescence was evaluated. After cold storage, CA and Ck had a significant effect on delaying development of browning. However, following the refrigerated period plus 2 days at 20°C (shelf-life), only the Ck treatment had a significantly lower percentage of browning compared to the control. The analysis of the relative mRNA levels of the candidate genes suggests an important anti-senescent effect of cold storage, as 13 genes showed a down-regulated profile compared to the corresponding expression profile at harvest. Combined with cold storage, the Ck treatment after shelf-life provided additional protection and affected the expression profiles of 3 genes: TL1, CBS and ERF. This response suggests a putative cellular regulatory mechanism of water loss and senescence in rachis that most likely involves ethylene and oxidative stress metabolism. Additionally, the short-term storage experiments indicated an up-regulation of chlorophyll breakdown-related genes after storage for 2 days at 20°C but not at 0°C. This finding suggests an early postharvest involvement of the chlorophyll degradation process at high temperatures.

Properties of PE-Coating Steel Pipes Used for Water Supply in Severely Cold and Salty Regions

Recently, polyethylene coating steel pipe has been extensively applied to water delivery in south-east China. However, similar applications in the north-west district where is severely cold and salty are seldom reported. This paper designed the refrigeration experiment, the freeze-thaw cycle experiment and the chemical immersion experiment after freeze-thaw, to test the PE coating steel pipe's reliability in the severely cold and salty region. The result showed that, after freeze-thaw or a period of refrigeration, a small number of dark spots appeared in the coating but didn’t change with the increase of freeze-thaw cycle times and the erosion of salt. The compositions were proved to be carbon and oxygen which indicated that the spots might be relative to the cryogenic stability of the coating rather than the corrosion of matrix steel. A crack and corrosion spot also appeared in test due to the excessively thick coating and the burr in steel substrate which can be eliminated by manufacturers through improving the coating formulas, surface pretreatment and coating process.

Cholesterol content and intramuscular collagen properties of pectoralis superficialis muscle of quail from different genetic groups

To study growth performance and meat quality traits (cholesterol content and intramuscular collagen properties) of quail, 3 trials were carried out. Trial 1 used males of generation 19 of the egg type Japanese quail (Coturnix japonica) selected previously (until generation 17) for low (n = 8) or high (n = 7) yolk cholesterol content as well as an unselected control (n = 11). Trial 2 used males of meat Pharaoh quail selected earlier (generations 1 to 6 and 9 to 11) on the basis of BW decrease after periodic deprivation of food (high decrease of weight, n = 10; low decrease of weight, n = 8) and unselected control (n = 10). Trial 3 compared males of English White quail, Manchurian Golden quail, and British Range quail. The birds were raised to 35 d of age. Quail were fed ad libitum commercial diets according to age and had free access to water. At slaughter, all birds were individually weighed (after a fasting period of 12 h), stunned, and decapitated. After the refrigeration period (24 h at 4°C), the left pectoralis superficialis muscle was removed from the carcasses, weighed, vacuum packaged, and stored frozen (-40°C) for analyses of cholesterol and intramuscular collagen (IMC; collagen and crosslink concentration). In trial 1, divergent selection for yolk cholesterol content did not significantly influence pectoralis superficialis muscle weight and IMC crosslinking of Japanese quail, whereas it significantly reduced growth and IMC amount. In addition, it had greater effect on the amount of cholesterol in meat; in fact, the meat of quail with low yolk cholesterol content contained lower cholesterol (-36.6%) than that of birds with high yolk cholesterol content. In trial 2, divergent selection on the basis of Pharaoh quail BW decrease altered IMC crosslinking, leading to variability in meat tenderness of Pharaoh quail. In trial 3, English White quail were significantly heavier than the other breeds.

Scombrotoxin poisoning: an important differential diagnosis for anaphylaxis

We report a case of scombrotoxin poisoning, an acute illness that develops within minutes to hours of eating poorly processed oily fish, such as tuna or mackerel. It presents with symptoms that can mimic an anaphylactic reaction. It is presumed to arise due to ingestion of histamine that is formed by contaminating bacteria that have flourished during periods of suboptimal refrigeration, following capture. Knowledge of this underdiagnosed malady as a potential differential diagnosis for patients presenting with symptoms suggestive of histamine release is important. It is a notifiable condition. The alternative diagnosis of anaphylaxis may have significant lifestyle implications for the patient. This article reports on one such presentation and the way that the diagnosis was explored.

Características químicas de abacaxi 'Pérola' após tratamento com calor e armazenagem em três temperaturas

Avaliou-se o efeito do tratamento térmico (40ºC por 24 horas) e de diferentes temperaturas de armazenamento (8ºC, 14ºC e 25ºC, a 90%UR), na conservação pós-colheita de abacaxis 'Pérola', colhidos no ponto de maturação "pintado". As avaliações foram realizadas no início (0 dia), visando à caracterização inicial dos frutos, e após 1; 5; 9; 13 e 17 dias, quando os mantidos sob refrigeração foram transferidos para condição ambiente (25ºC, 75-80% UR), e avaliados aos 21; 25 e 29 dias. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial (2x3x9), tendo-se os frutos tratados termicamente ou não, o armazenamento a 25ºC, 14ºC e 8ºC e nove épocas de avaliação. Os frutos foram avaliados quanto à ocorrência de podridões e de escurecimento interno, aparência e coloração da polpa, teores de sólidos solúveis (SS), acidez titulável (AT), açúcares solúveis totais e redutores e ácido ascórbico, além da relação SS/AT. Os resultados indicam que a coloração da polpa se tornou mais amarela durante o período refrigerado, enquanto os valores da AT aumentaram. Neste período, a relação SS/AT reduziu-se, mas aumentou com a transferência dos frutos para o ambiente, enquanto os teores de açúcares solúveis totais e redutores diminuíram, e estabilizaram-se. Os teores de ácido ascórbico mantiveram-se sem diferenças significativas, mas com tendência de aumento. Os frutos mantidos sob refrigeração apresentaram sintomas de injúria pelo frio, que apareceram em 8 dias, após serem levados ao ambiente, e com maior intensidade nos tratados termicamente.

In vivogene expression of cold shock and other stress-related genes inVibrio vulnificusduring shellstock temperature control conditions in oysters

To determine Vibrio vulnificus response to shellstock refrigeration conditions while the bacterium was embedded in oysters (in vivo). Depurated oysters were artificially inoculated with V. vulnificus. Several cold-shock conditions were examined according to the National Sanitation Shellfish Program guidelines. Culturability of cells along the refrigeration period was measured using specific colony dot-blot. Gene expression of putative cold-shock genes (csp1, csp3, csp4 and csp5) as well as three stress-related genes (rpoS, oxyR and katG) was determined by reverse transcriptase polymerase chain reaction. Vibrio vulnificus exhibited a decline in cell viability after cold shock but a cold adaptation response was observed when oysters were kept at suboptimal (15 degrees C) temperatures. 16SrRNA, and rpoS genes were constitutively expressed while expression of csp genes varied among strains and time points. Vibrio vulnificus culturability was reduced after oysters were subjected to shellstock refrigeration conditions. When V. vulnificus was allowed to acclimate to cold temperatures, its survival after cold shock was higher. None of the cold shock genes analysed behaved as csp type I genes. A model for artificially inoculated specific strains of V. vulnificus into oysters has been established. For the first time, V. vulnficus gene expression was assessed with the pathogen embedded in oysters.

Suitability of high pressure-homogenized milk for the production of probiotic fermented milk containing Lactobacillus paracasei and Lactobacillus acidophilus

High pressure homogenization (HPH) is one of the most promising alternatives to traditional thermal treatment for food preservation and diversification. In order to evaluate its potential for the production of fermented milks carrying probiotic bacteria, four types of fermented milks were manufactured from HPH treated and heat treated (HT) milk with and without added probiotics. Microbiological, physicochemical and organoleptic analyses were carried out during the refrigerated period (35 d at 4 degrees C). HPH application to milk did not modify the viability of the probiotic cultures but did increase the cell loads of the starter cultures (ca. 1 log order) compared with traditional products. The coagula from HPH-milk was significantly more compacted (P<0.05) (higher firmness) than that obtained with HT-milk, and it had the highest values of consistency, cohesiveness and viscosity indexes compared with fermented milks produced without HPH treatment. All the samples received high sensory analysis scores for each descriptor considered. HPH treatment of milk can potentially diversify the market for probiotic fermented milks, especially in terms of texture parameters.

Preservation of the Activity of Supported Gold Catalysts for CO Oxidation

Procedures leading to the preservation of activity of supported gold catalysts for CO oxidation are reviewed. The inclusion of iron as Fe(OH)3 in preparing catalysts using tin oxide, ceria and zirconia as supports gives better activity and much improved stability with time-on-stream. In the case of Au/Fe-SnO2 (0.5–0.9% Au), the effect is maximal with ~4% Fe. The stability of catalysts based on ceria as support is also much better when small amounts of either iron or lanthanum during preparation of the support by thermal decomposition of nitrates. Au/SnO2 catalysts often suffer initial deactivation followed by an increase in activity with time-on-stream; a period of refrigeration (7d) induces an excellent stability at high conversion.

The incorporation of dehydrated rosemary leaves in the rations of turkeys and their impact on the oxidative stability of the produced raw and cooked meat

Thirty-six 12-week-old turkeys were distributed into six groups and were raised for 4 weeks on rations containing 0%, 0.5% or 1.0% dehydrated rosemary leaves as antioxidant in the presence of α-tocopheryl acetate from 10 to 300 mg/kg. Following slaughtering, breast and thigh meat samples, raw or cooked, from all six groups were collected to be refrigerated at 4°C for 9 days. All stored samples were submitted to analysis for their concentration in malondialdehyde (MDA), a lipid oxidation marker, and α-tocopherol. The results showed that the rations containing 300 mg/kg α-tocopheryl acetate increased the mean α-tocopherol content of the breast and thigh significantly (P <0.05) compared with the respective control values. No significant (P>0.05) changes could be observed in the α-tocopherol content of breast and thigh of turkeys consuming rations containing up to 1% dehydrated rosemary leaves. The refrigeration of the meats led to spontaneous increase in the MDA content of the breast and thigh meat samples. Samples from turkeys fed rations containing 300 mg/kg α-tocopheryl acetate showed the lowest mean levels of MDA after the 9-day refrigerated period. The incorporation of rosemary in the rations led to a modest decrease in the formation of MDA in the meats compared with the respective mean control values. The combination of α-tocopheryl acetate and rosemary was not associated with an additional decrease in MDA formation.