Effect of packaging conditions on shelf-life of fresh foal meat

The objective was to determine the shelf life of foal meat (Longissimus dorsi) stored in four different packages: (i) vacuum, (ii) overwrap and (iii) two modified atmospheres (MAP): high O(2) MAP (80% O(2)+20% CO(2)) and low O(2) MAP (30% O(2)+70% CO(2)) stored at 2 °C during 14 days. Shelf life evaluation was based on pH, colour, lipid and protein oxidation, microbial counts and sensory assessment of odour, colour and appearance. Based on aerobic bacterial counts, the shelf life of foal meat samples in overwrap and high O(2) MAP packages would be 10 days at most, almost 14 days in low O(2) MAP and more than 14 days in vacuum packaging. Scores for sensorial evaluation were unacceptable after 10 days of storage in samples in overwrap and MAP packs, but they were still acceptable in vacuum ones. Moreover, for all packaging conditions except vacuum, which remained constant, a decrease in redness (a*) and an increase in carbonyl content and TBAR'S values was observed with storage time. High O(2) levels negatively affected foal meat quality, while anaerobic conditions extended shelf life to 14 days.     

Shelf life of beef from local Spanish cattle breeds stored under modified atmosphere

Beef steaks from six Spanish cattle breeds (Asturiana de los Valles, Morucha, Parda Alpina, Pirenaica, Rubia Gallega and Retinta) were packaged under modified atmosphere (60% O(2), 30% CO(2) and 10% N(2)). Water loss, pH, thiobarbituric acid values (TBA), aerobic plate counts, lactic acid bacteria and Enterobacteriaceae counts, CIE L*a*b* colour values and the sensory properties of odour and colour were recorded before packaging (day 0) and after 5, 10 and 15 days of storage. A significant interaction (P<0.05) between breed and storage time was found for all variables, except water loss. Values of pH were between 5.3 and 5.6; maximum water loss (2.64%) was reached after 10 days of storage; aerobic plate counts, lactic acid bacteria and Enterobacteriacea counts were lower than 10(7) CFU/g, and L* increased with storage time while a* decreased (P<0.05). The maximum shelf life of beef assessed by sensory evaluation (regarding colour and odour degradation) was between days 5 and 10 in meat from Retinta breed and between days 10 and 15 in meat from the other breeds, shelf life was probably limited by lipid oxidation.     

Combined effect of oregano essential oil and modified atmosphere packaging on shelf-life extension of fresh chicken breast meat, stored at 4 degrees C

The combined effect of oregano essential oil (0.1% and 1% w/w) and modified atmosphere packaging (MAP) (30% CO2/70% N2 and 70% CO2/30% N2) on shelf-life extension of fresh chicken meat stored at 4 degrees C was investigated. The parameters that were monitored were: microbiological (TVC, Pseudomonas spp., lactic acid bacteria (LAB), yeasts, Brochothrix thermosphacta and Enterobacteriaceae), physico-chemical (pH, TBA, color) and sensory (odor and taste) attributes. Microbial populations were reduced by 1-5 log cfu/g for a given sampling day, with the more pronounced effect being achieved by the combination of MAP and oregano essential oil. TBA values for all treatments remained lower than 1 mg malondialdehyde (MDA) kg(-1) throughout the 25-day storage period. pH values varied between 6.4 (day 0) and 5.9 (day 25). The values of the color parameters L*, a* and b* were not considerably affected by oregano oil or by MAP. Finally, sensory analysis showed that oregano oil at a concentration of 1% imparted a very strong taste to the product for which reason these lots of samples were not scored. On the basis of sensory evaluation a shelf-life extension of breast chicken meat by ca. 3-4 days for samples containing 0.1% oregano oil, 2-3 days for samples under MAP and 5-6 days for samples under MAP containing 0.1% of oregano oil was attained. Thus oregano oil and MAP exhibited an additive preservation effect.     

包装方式和宰后不同时间包装对羊肉品质的影响

为探究包装方式和宰后不同时间包装对羊肉贮藏品质的影响,本研究对宰后1 h热分割羊肉和冷却成熟24 h后的分割羊肉分别进行热收缩包装、真空包装、贴体包装、50%（体积分数,下同）O2+50%CO2气调包装,测定其在（2±2）℃贮藏过程中pH值、色泽、贮藏损失率、蒸煮损失率、离心损失率、剪切力、挥发性气味的变化。结果表明：与宰后24 h包装相比,宰后1 h包装羊肉pH值在贮藏14 d时更高,但其贮藏期间色泽较好,色泽稳定性更高,贮藏损失率更低。从整体来看,3种真空处理（热收缩包装、真空包装、贴体包装）羊肉嫩度均优于气调包装羊肉,且宰后1 h包装时真空条件处理对羊肉嫩化效果最好,宰后24 h羊肉在贮藏前期气调包装对羊肉嫩化效果较好;而无论何时包装,热收缩包装和气调包装羊肉贮藏损失率均显著小于其他处理组（P<0.05）,在贮藏前期色泽及稳定性较好,但贮藏后期色泽稳定性下降明显,气调包装羊肉在14 d时已部分发绿,贮藏21 d时挥发性气味变化显著。综上,宰后1 h包装有利于提高羊肉贮藏期间色泽及持水力,改善真空处理羊肉嫩度,宰后24 h包装可提高50%O2+50%CO2气调包装羊肉贮藏前期...     

包装材料对高氧气调包装冷鲜肉品质变化的影响

气调包装能有效延长冷却肉的货架期,但是不同阻隔性的包装材料对冷却肉的保质期影响差异显著,因此选用3种不同阻隔性的包装材料,对冷鲜肉进行高氧气调包装(35% CO2、65% O2),测定冷鲜肉在贮藏期的菌落总数、大肠菌群、色泽、挥发性盐基态氮、汁液流失率和pH值等指标,观察不同阻隔性的材料对冷却肉货架期品质的影响。结果表明：高氧包装条件下,高阻隔材料包装的冷却肉在贮存10d菌落总数已经超标,pH值在贮存期内处于二级鲜肉的范围内;中阻隔包装材料包装的冷却肉菌落总数对数值在保质期内未超过6(lg(CFU/g)),但是肉色保持的较好,感官评价相对较好,但是汁液流失较大;低阻隔包装材料低阻隔性的包装材料菌落变化最大,13d时菌落总数对数值达到6.46(lg(CFU/g)),肉的色泽相对较差,气味和总体可接受性也较差,因此,中阻隔性包装材料效果较好。     

Effectiveness of active and modified atmosphere packaging on shelf life extension of a cheese tart

This study evaluated the shelf life extension of a cheese cake subjected to modified atmosphere (MAP) and active packaging (AP). Cheese cakes were packaged under different N₂/CO₂ ratios (70/30 and 20/80) (MAP batches), by placing a sachet of an iron oxide-based oxygen absorber inside trays (AP batch) and with air (air batch). Changes in microbial growth, in-package gas composition, chemical–physical parameters including texture and sensory attributes were monitored for 48 days at 20 °C. AP allowed a mould-free cheese cake shelf life of 48 days, MAP extended the shelf life of samples packaged under 30% and 80% CO₂ up to 14 and 34 days, respectively, whereas tarts stored with air spoiled after 7 days. MAP resulted in a significant increase in hardness after 14 days of storage, whereas AP tarts recovered the initial texture after 48 days. Panellists judged AP tarts over the acceptability threshold during the whole shelf life of cheese tarts.     

Shelf life of fresh foal meat under MAP, overwrap and vacuum packaging conditions

The objective of this study was to investigate the physico-chemical properties, the microbial counts and the sensory properties' changes of foal steaks packed under various conditions. The experimental packaging systems were: (i) vacuum packaging (VP), (ii) overwrap packaging and (iii) two modified atmosphere packaging methods (MAP): high O(2) MAP (80% O(2)+20% CO(2)) and low O(2) MAP (30% O(2)+70% CO(2)). The meat was stored at 2°C during 14days and tested for pH, colour, lipid and protein oxidation, microbial counts and sensory assessment of odour, colour and appearance. Of the two MAP, overwrap and VP, both MAP were the most effective treatments for the inhibition of the total viable counts (TVC), Pseudomonas spp., psychrotrophic aerobic bacteria, lactic acid bacteria, Enterobacteriaceae as well as moulds and yeast. According to the sensory evaluation, foal steaks packed under overwrap and MAP treatments resulted unacceptable after 7days of storage, whereas the vacuum-packed meat was still acceptable. Moreover, the redness value decreased significantly (P<0.001) with all treatments during the storage time, except for the vacuum packs, which increased significantly (P<0.001). Finally, foal steaks from overwrap packaging and MAP conditions had a greater increase of TBAR'S values and carbonyl content during the storage time. High O(2) levels affected foal meat quality negatively, while anaerobic conditions extended the meat's shelf life up to 14days.     

Nanoencapsulation Approach to Improve Antimicrobial and Antioxidant Activity of Thyme Essential Oil in Beef Burgers During Refrigerated Storage

In this study, thyme essential oil (TEO) loaded chitosan nanoparticles (CS-NP-TEO) are prepared by a two-step process including oil/water emulsion and ionic gelation. Five batches of burgers were prepared by following formulation: control (without any TEO), F-0.05-TEO (0.05 % of free TEO), F-0.1-TEO (0.1 % of free TEO), E-0.05-TEO (0.05 % of encapsulated TEO), E-0.1-TEO (0.1 % of encapsulated TEO), and AA-0.05 (0.05 % of ascorbic acid). All samples treated with TEO significantly reduced the population of investigated microbial counts (P?<?0.05) compared to the control during 8 days of storage. At the end of storage, E-0.05-TEO and E-0.1-TEO, presented, respectively, 2.2 and 3 log cycles reduction of Enterobacteriaceae, along with 3.1 and 3.7 log cycles reduction of Staphylococcus aureus. Oxymyoglobin content and redness values reduced with the increase of storage time for all samples. However, AA-0.05 and E-0.1-TEO samples were more efficient at inhibiting discoloration in comparison with E-0.05-TEO and burgers treated with free TEO after 6th day of storage. A significant improvement (P?<?0.05) in the reduction of thiobarbituric acid reactive substances (TBARS) amount was found for all TEO treated burgers in comparison to control samples after 8 days chilled storage. According to the results of sensory analyses, F-0.1-TEO and AA-0.05 samples at 4 days and F-0.05-TEO sample at 8 days of storage were rejected by assessors and considered as an unacceptable case. On the basis of our results, the encapsulation of TEO in chitosan nanoparticles may be a promising technology for the control of undesirable microbial, chemical, and sensorial changes in meat products.     

饲料中添加牛至精油对红罗非鱼货架期的影响

研究牛至精油对红罗非鱼品质和货架期的影响。以空白添加组为对照,分别在对照组饲料中添加250、500、1 000、2 000 mg/kg牛至精油,经过20周养殖实验,红罗非鱼在4℃条件下冷藏0、7、14、21 d,在每个冷藏时间点检测红罗非鱼物理化学特性、微生物定性定量分析和感官分析评估,以判定其腐败程度。结果表明,牛至精油添加对红罗非鱼体色、硫代巴比妥酸反应值和总挥发性盐基氮含量有显著的影响。1 000、2 000 mg/kg牛至精油可有效降低冷藏鱼片的肠杆菌和大肠菌群数量。感官分析表明,红罗非鱼体的质量指数与牛至精油的添加量没有显著相关,对照组的货架期为16 d,牛至精油组的货架期为18 d,但与添加量无显著相关。     

Potential of a simple HPLC-based approach for the identification of the spoilage status of minced beef stored at various temperatures and packaging systems

The shelf life of minced beef stored (i) aerobically, (ii) under modified atmosphere packaging (MAP), and (iii) under MAP with oregano essential oil (MAP/OEO) at 0, 5, 10, and 15 °C was investigated. The microbial association of meat and the temporal biochemical changes were monitored. Microbiological analyses, including total viable counts (TVC), Pseudomonas spp., Brochothrix thermosphacta, lactic acid bacteria, Enterobacteriaceae, and yeasts/moulds, were undertaken, in parallel with sensory assessment, pH measurement and HPLC analysis of the organic acid profiles. Spectral data collected by HPLC were subjected to statistical analysis, including principal component analysis (PCA) and factorial discriminant analysis (FDA). This revealed qualitative discrimination of the samples based on their spoilage status. Partial least squares regression (PLS-R) was used to evaluate quantitative predictions of TVC, Pseudomonas spp., Br. thermosphacta, lactic acid bacteria, Enterobacteriaceae, and yeasts/moulds. Overall, the HPLC analysis of organic acids, was found to be a potential method to evaluate the spoilage and microbial status of a meat sample regardless of the storage conditions. This could be a very useful tool for monitoring the quality of meat batches during transportation and storage in the meat food chain.     

冷鲜肉高氧气调保鲜包装研究

为延长冷鲜肉的货架期,本研究以PP材质托盘盛装,PP膜封盒,充入不同比例的气体成分对冷鲜肉进行气调包装.在温度4℃、湿度80％的恒定条件下,分别研究了25％ O2＋ 75％ CO2、45％O2＋55％ CO2、65％ O2＋ 35％ CO2的3种不同气体组分的气调包装对冷鲜肉的感官指标、色度、pH值和挥发性盐基氮含量等指标的影响,并且通过与大气对照组的对比,对冷鲜肉气调保鲜包装第6天的保鲜效果进行雷达直观定性分析.结果表明,65％O2＋35％ CO2组气调包装的保鲜效果明显好于其他实验组,冷鲜肉的货架期延长了6天.     

不同包装方式对捻转贮藏过程中品质变化的影响

为研究不同包装方式对捻转贮藏过程中品质变化的影响,以捻转为研究对象,采取PE普通包装、真空包装和气调包装(70% N₂+30% CO₂)3种不同包装方式处理,在4℃下贮藏,并隔天测定感官、水分、pH、色泽、菌落总数、质构等指标。结果表明:不同包装方式对捻转品质变化的影响存在显著性差异(p<0.05),其中气调包装贮藏效果最佳;PE普通包装和真空包装的样品在贮藏6 d后感官评分就明显下降,而气调包装的样品在贮藏10 d后仍有较高的评分;同时气调包装能抑制微生物繁殖,延缓样品pH、水分下降速率,硬度、咀嚼性也低于另两种包装方式,弹性、内聚性则差异不显著(p>0.05)。综合比较分析,PE普通包装、真空包装、气调包装样品的货架期分别为4、6和10 d。因此,将气调包装应用于捻转,能较好维持样品的色泽和风味,保证产品品质,延长其货架期。     

不同含氧气调包装方式对调理鸭肉制品的保鲜效果

为延长调理鸭肉制品货架期,将调理后的鸭肉分别以托盘包装为对照,用不同含氧气调包装方式（MAP1（20% CO2＋80% N2）、MAP2（20% CO2＋40% O2＋40% N2）、MAP3（20% CO2＋80% O2））对调理鸭肉制品进行保鲜处理（0～4 ℃）,测定调理鸭肉贮藏期间微生物指标和生理生化指标。结果表明：与托盘包装组相比,3 种气调包装方式均能有效抑制调理鸭肉中微生物生长,减少挥发性盐基氮产生;含氧组（MAP2和MPA3）的保鲜效果显著优于MAP1组和对照组（P＜0.05）,含氧组的保质期均为12 d;在贮藏12 d时,MAP2组的TBARS值和肠杆菌数显著低于MAP3组（P＜0.05）,MAP3组的菌落总数显著低于MAP2组（P＜0.05）,且这两组的TVB-N含量和L*值均无显著差异（P＞0.05）。综合分析,MAP2包装对调理鸭肉制品保鲜效果最好。     

Combined effect of irradiation and modified atmosphere packaging on shelf-life extension of chicken breast meat: microbiological, chemical and sensory changes

In the present study the combined effect of gamma irradiation (2 and 4 kGy) and modified atmosphere packaging (MAP) (30% CO₂/70% N₂ and 70% CO₂/30% N₂) on shelf life extension of fresh chicken meat stored under refrigeration was investigated. The study was based on microbiological (TVC, Pseudomonas spp., Lactic Acid Bacteria, Yeasts, Brochothrix thermosphacta, Enterobacteriaceae), physicochemical (pH, TBA, color) and sensory (odor, taste) changes occurring in chicken samples. Microbial populations were reduced by 1–5 log cfu/g for a given sampling day depending on the specific treatment. The effect was more pronounced in the case of the combination of MAP (70% CO₂/30% N₂) and the higher irradiation dose of 4 kGy. Of the chemical indicators of spoilage, TBA values for all treatments remained lower than 1 mg malondialdehyde (MDA)/kg meat throughout the 25 day storage period. pH values varied between 6.4 (day 0) and 5.9 (day 25). The values of the color parameters L*, a* and b* were not considerably affected by MAP. Irradiation resulted in a small increase of the parameter a*. Irradiation had a greater effect in extending the shelf life of chicken as compared to MAP. Sensory evaluation showed that the combination of irradiation at 4 kGy and MAP (70% CO₂/30% N₂) resulted in the highest shelf-life extension by 12 days compared to the air packaged samples.     

Shelf life of ready to use peeled shrimps as affected by thymol essential oil and modified atmosphere packaging

In this work the influence of different packaging strategies on the shelf life of ready to use peeled shrimps was investigated. First, the effectiveness of the coating (Coat) and the active coating loaded with different concentrations of thymol (Coat-500, Coat-1000, and Coat-1500) on the quality loss of the investigated food product packaged in air was addressed; afterwards, the thymol concentration that had shown the best performance was used in combination with MAP (5% O₂; 95% CO₂). Microbial cell load of main spoilage microorganisms, pH and sensorial quality were monitored during the refrigerated storage. Results of the first step suggested that the sole coating did not affect the microbial growth. A slight antimicrobial effect was obtained when the coating was loaded with thymol and a concentration dependence was also observed. Moreover, the active coating was effective in minimizing the sensory quality loss of the investigated product, it was particularly true at the lowest thymol concentration. In the second step, the thymol concentration (1000 ppm) that showed the strike balance between microbial and sensorial quality was chosen in combination with MAP. As expected, MAP significantly affected the growth of the mesophilic bacteria. In particular, a cell load reduction of about 2 log cycle for the samples under MAP respect to that in air was obtained. Moreover, the MAP packaging inhibited the growth of the Pseudomonas spp. and hydrogen sulphide-producing bacteria. The MAP alone was not able to improve the shelf life of the uncoated samples. In fact, no significant difference between the control samples packaged in air and MAP was observed. Whilst, the use of coating under MAP condition prolonged the shelf life of about 6 days with respect to the same samples packaged in air. Moreover, when the MAP was used in combination with thymol, a further shelf life prolongation with respect to the samples packaged in air was observed. In particular, a shelf life of about 14 days for the active coating under MAP compared to the same samples in air (5 days) was obtained.     

Combined effect of natural essential oils, modified atmosphere packaging, and gamma radiation on the microbial growth on ground beef

Selected Chinese cinnamon, Spanish oregano, and mustard essential oils (EOs) were used in combination with irradiation to evaluate their ability to eliminate pathogenic bacteria and extend the shelf life of medium-fat-content ground beef (23% fat). Shelf life was defined as the time when the total bacterial count reached 10(7) CFU/g. The shelf life of ground beef was determined for 28 days at 4 degrees C after treatment with EOs. The concentrations of EOs were predetermined such that sensory properties of cooked meat were maintained: 0.025% Spanish oregano, 0.025% Chinese cinnamon, and 0.075% mustard. Ground beef samples containing EOs were then packaged under air or a modified atmosphere and irradiated at 1.5 kGy. Ground beef samples (10 g) were taken during the storage period for enumeration of total mesophilic aerobic bacteria, Escherichia coli, Salmonella, total coliforms, lactic acid bacteria, and Pseudomonas. Mustard EO was the most efficient for reducing the total mesophilic aerobic bacteria and eliminating pathogenic bacteria. Irradiation alone completely inhibited the growth of total mesophilic aerobic and pathogenic bacteria. The combination of irradiation and EOs was better for reducing lactic acid bacteria (mustard and cinnamon EOs) and Pseudomonas (oregano and mustard EOs). The best combined treatment for extending the shelf life of ground beef for up to 28 days was EO plus irradiation (1.5 kGy) and modified atmosphere packaging.     

Effects of three preservative agents on the shelf life of vacuum packaged Chinese-style sausage stored at 20°C

The influence of 3% sorbitol, 3% sodium lactate and 100 mg/kg nisin on the shelf life of vacuum packaged Chinese-style sausage stored at 20°C was studied. Growth of microbiological populations (aerobe, anaerobe, lactic acid bacteria, leuconostocs) and slime formation on the sausage were not retarded during storage by addition of nisin. Sorbitol lowered the initial water activity of the sausage, however, microbiological spoilage accompanied with pH decline, increase in volatile basic nitrogen compounds and a sour odour defect were observed after 10 days storage. Sodium lactate was bacteriostatic as it inhibited microbial as well as chemical changes during storage so that the shelf life was 25 days at 20°C. The dextran content of the vacuum packaged Chinese-style sausage indicated the spoilage 2-3 days earlier than that seen by other chemical assays or sensory evaluation.     

Effects of dietary vitamin e supplementation and packaging on the quality of minced beef

Friesian cattle, aged 26-27 months, were fed a diet supplemented with 2000IU α-tocopheryl acetate/kg feed/day and another group was fed a basal diet (20IU/kg feed/day) for approximately 50 days prior to slaughter. Following frozen storage (-20°C for 8 weeks) semimembranosus muscles from basal and α-tocopheryl acetate supplemented cattle were minced and vacuum packaged, aerobically packaged or packaged under modified atmospheres (MAP) (30% O(2): 70% CO(2); 70% O(2): 30% CO(2); 80% O(2): 20% CO(2)). Samples were held under refrigerated (4°C) display (fluorescent lighting, 616 lux) for eight days. Vacuum-packaged samples were held under similar conditions but in complete darkness and allowed to bloom for a minimum of 4hr prior to taking colour readings. TBARS values and Hunter a values in minced beef were measured every two days. α-Tocopherol concentrations were significantly (p<0·05) higher in minced meat samples from the supplemented group than in the basal group. Significant (p<0·05) reductions in α-tocopherol concentrations in supplemented meat samples were observed with increased concentrations of oxygen in different packaging systems after eight days of refrigerated storage. TBARS values were reduced over the whole retail display period for all packaging systems when α-tocopheryl acetate supplemented beef was used. TBARS values increased as oxygen levels increased in MAP. Hunter a values showed that vitamin E supplementation in combination with vacuum packaging and MAP improved the colour stability of meat during the first 4 days of storage, however, the failure of MAP to extend meat colour for longer periods of time was probably the result of prior storage at -20°C for 8 weeks.     

Effect of different storage conditions on E. coli O157:H7 and the indigenous bacterial microflora on lamb meat

Lamb chops inoculated with 2.23-2.83 log cfu/g of E. coli O157:H7 strain NCTC 12900 were packed in air (AP), vacuum (VP), and two modified atmospheres (MAP) consisting of 100% CO2 and a commercial mixture of 35% CO2/35% O2/30% N2. All samples (initial total counts <3.5 log cfu/g) were stored in a commercial cold storage facility set at 4 degrees C and one AP trial also at 12+/-1 degrees C in a temperature controlled incubator. Pathogen and indigenous flora evolution, physicochemical and sensory changes, surface packages temperature and MAP gas composition were monitored throughout the lamb meat shelf life. Temperature monitoring revealed that during chilled storage packed chops exceeded 7 degrees C about 3% of the time for periods of 10-20 min at 6 h intervals corresponding to defrosting cycles. In AP samples under these conditions, the E. coli O157:H7 strain had an overall increase of 0.48 log cfu/g by day 12. This increase, which may be regarded as an artefact of the sampling procedure, might also be a response to fluctuating temperatures. Regardless of rapid proliferation of the background microflora on AP lamb meat kept at 12+/-1 degrees C, the pathogen significantly increased by 2.35 log cfu/g after nine days. There was a slight decrease (0.20 log cfu/g) of the pathogen numbers after four weeks cold storage in VP despite a significant increase in lactic acid bacteria (LAB). With a relatively small outgrowth of LAB, chilled storage in 100% and 35% CO2 resulted in significant differences compared to similar conditions in air (decrease from initial numbers of 0.80 and 0.45 log cfu/g, respectively). Our data confirm the importance of effective temperature control to prevent pathogen growth on raw meat and also that contaminated meat remains hazardous regardless of refrigeration and protective packaging. Further studies are needed to determine the behaviour of E. coli O157:H7 at temperatures that fluctuate around the minimum for growth.     

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

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