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1.
The effect of dietary supplementation with vitamin E vs the in vitro addition of vitamin E on the colour stability of pasteurised comminuted pork shoulder model products was studied. Products were either manufactured with normal amounts of nitrite and ascorbate or with reduced levels of the additives. Half of the samples of sliced products from control meat (CON), from control meat supplemented in vitro with 5 and 50 mg kg-1 vitamin E and from meat derived from pigs receiving vitamin E supplements (SUP) were packaged under vacuum (VAC) and half in low-oxygen modified atmosphere packs (FOG). Duplicate packages were stored in the dark and under constant illumination for 21 days at 7 °C. For the illuminated VAC-packaged products, significant temporary decreases in the redness values were observed for CON and the in vitro addition of 5 mg kg-1 vitamin E to CON. Both dietary supplementation with approximately 5 mg kg-1 extra vitamin E and the in vitro addition of 50 mg kg-1 vitamin E to CON were effective in preventing the temporary decrease in redness values. At the end of the experiment, the redness values of the VAC products approximated initially measured levels. The colour of the illuminated FOG-packaged products was stable throughout storage and the redness values of the SUP products were significantly better than those of the CON products. The in vitro addition of vitamin E had no effect on redness values here. The colour stability of VAC-packaged products containing the combination of reduced levels of nitrite and ascorbate was diminished in the initial period of illuminated storage. Similar effects were not observed for FOG-packaged products.  相似文献   

2.
Houben JH  van Dijk A 《Meat science》2001,58(4):259-407
The effect of supplementation of vitamin E (2025 IU animal−1 day−1) in the diet of beef bulls on the colour stability of pasteurized beef ham was studied. Control and enriched diets were provided for the last 136 days before slaughter. Pasteurized hams were manufactured from Mm. semitendinosus from eight animals per dietary group. Half of the samples of sliced ham from control (CON) and supplemented (SUP) bulls were packaged under vacuum (VAC) and half in low-oxygen modified atmosphere packs (FOG, gas mixture: CO2/N2=50/50). The packages were kept under constant illumination for 28 days at 8°C. During storage, the number of colony-forming units (CFU) reached a maximum of 5x107 g−1. The microflora was dominated by lactic acid bacteria. The supplementation with vitamin E showed no effect on microbial growth. Lipid oxidation was stable during storage. A significant difference between both dietary groups was detected for the decrease in the redness values during storage. Redness values of CON vacuum-packaged samples decreased (P < 0.01) with time, whereas those for the SUP products only tended to decrease. The redness values of FOG-packed ham were higher than those of VAC-packed ham at the end of the display period, irrespective of the dietary group. Overall, colour appeared to be more stable in the FOG-packed products than in the VAC-packed products. It can be concluded that dietary supplementation of bulls with vitamin E appears to offer only a minor improvement in colour stability over current feeding regimens when the Mm. semitendinosus are used to make cured, pasteurized ham-type products.  相似文献   

3.
The effect of supplementation of vitamin E (200 W kg−1 feed) in the diet of pigs on colour stability and lipid oxidation in minced pork was studied. Control and enriched diets were provided for the last 12 weeks before slaughter. Half of the samples of minced shoulder meat from control and supplemented pigs were packaged on trays with oxygen-permeable overwraps and half in modified atmosphere packs (initial gas mixture: O2/CO2/N2 = 66/ 27/7). Meats were stored for 10 days at 7 °C in an illuminated retail display cabinet. The meat from vitamin E-supplemented pigs was more resistant to lipid oxidation than was the control meat. Gas packaging appeared to increase lipid oxidation in control meat, whereas lipid oxidation was stable in meat from vitamin E-supplemented pigs. Colour stability for gaspacked meat was comparable for both dietary groups. However, oxygen-permeable overwraps had a negative effect on colour stability in vitamin E-enriched meat. The reason for this is not known. The shelf-life of enriched and control meat was similar. Thus supplementation of pig feeds with vitamin E is recommended if an improved stability against lipid oxidation of (minced) pork is required.  相似文献   

4.
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.  相似文献   

5.
Five Simmentaler type calves were fed diets supplemented with 500 mg vitamin E per day and five fed control diets. Rump steaks from each carcass were PVC-overwrapped and bulk packaged in 100% CO, or 20% CO2:80% O2. Bulk packs were stored up to 42 days at 4°C and steaks displayed up to 7 days at 4°C. Bacterial counts of rump steaks from either packaging treatment were not significantly influenced during bulk storage or retail display by supplementation with dietary vitamin E. Both packaging treatments delayed bacterial growth during bulk storage. Aerobic plate counts of rump steaks stored in 100% CO2 were lower than those of rump steaks stored in 20% CO2: 80%: O2. This study showed that rump steaks supplemented with dietary vitamin E can be bulk packaged in 20% CO2: 80% O2 or 100% CO2 and stored for up to 42 days with shelf life of 4–7 days.  相似文献   

6.
Thirty Large White×Great York gilts were fed six experimental diets containing three levels of poly and monounsaturated fatty acids. Within each dietary fat treatment, one group was fed a basal level of vitamin E (20 mg α-tocopheryl acetate/kg diet) and the other group received a supplemented level (200 mg α-tocopheryl acetate/kg diet). Concentration of α-tocopherol was significantly higher in hams from pigs fed supplemented dietary levels of vitamin E (P<0.0001), but no significant effect of dietary fat was observed. Dietary vitamin E supplementation reduced the concentration of thiobarbituric acid reactive substances after 9 days storage of sliced samples (P<0.0001), while dietary fat source showed no significant effect. Significantly lower oxidation was observed in ham homogenates from pigs fed higher concentrations of monounsaturated fatty acids after 120 min of incubation under pro-oxidant conditions (P=0.013). No effect of dietary treatment was observed in ham volatile aldehyde profile. No significant effect of dietary vitamin E was observed on surface redness during storage, but a significant effect was observed for luminosity after 7 days of storage (P=0.033). Hams from pigs fed diets enriched in monounsaturated fatty acid showed higher ‘a’ values (P=0.040) in stored sliced samples. Sensory evaluation revealed a significant effect of dietary vitamin E on redness of ham slices (P<0.001). Dietary supplementation with vitamin E also produced a significantly higher odour and flavour intensity (P=0.006 and P=0.01 respectively). Dry cured ham samples from pigs fed higher amounts of monounsaturated fatty acids showed a significantly higher consistency fat than those from pigs fed polyunsaturated fatty acids.  相似文献   

7.
The effects of modified atmosphere (80% O2: 20% CO2) and illumination on the discoloration rate of pork bone (lumbar vertebrae) and muscle (longissimus lumborum), and on muscle lipid stability were studied in vitamin E-supplemented and unsupplemented pigs. Bone-in pork chops were placed in 80% O2: 20% CO2 at 0 °C and stored for 5 days in the dark. The chops were then displayed under (a) fluorescent light in air or modified atmosphere or (b) in air with or without illumination. Lipid oxidation was increased by the modified atmosphere packaging but this detrimental effect was offset by vitamin E supplementation. Higher supplementation levels (198 and 207mg/kg) improved bone color stability regardless of the packaging atmosphere or the lighting conditions. Although vitamin E supplementation improved muscle color stability during display in air or modified atmosphere, the benefit of supplementation on muscle color was detectable only for illuminated storage.  相似文献   

8.
Fresh beef steaks, either sprayed on the surface with a solution of rosemary and vitamin C or not sprayed, were packaged in 70%O2+20%CO2+10%N2 and displayed at 1±1 °C without illumination or illuminated by a standard fluorescent lamp, a low-UV, colour-balanced lamp (Promolux®), or the fluorescent lamp with a UV filter. Metmyoglobin formation, lipid oxidation (2-thiobarbituric acid reactive substances), instrumental colour (CIE L*, a*, b*), psychrotrophic bacterial counts (PCA) and sensory discolouration and off-odour were determined. Results showed that the use of the antioxidant mixture of rosemary and vitamin C together with the absence of UV radiation significantly reduced the rates of metmyoglobin formation and lipid oxidation, as well as microbial growth, and extended the display life from about 10 to about 20 days.  相似文献   

9.
The effect of addition of vitamin E (2025 IU animal(-1) day(-1)) to the diet of beef bulls on the colour stability and lipid oxidation of minced beef was studied. Control and enriched diets were provided for the last 136 days before slaughter. Batches of freshly minced meat were prepared containing approximately 1.3 and 22.2 wt% fat, respectively. Half of the samples of minced meat from control (CON) and supplemented (SUP) beef were packaged on trays with oxygen-permeable over wraps and half in modified atmosphere (MA) packs (initial gas mixture: O(2)/CO(2)/N(2)=65/25/10). The minced beef was stored for 10 days at 7°C in an illuminated environment. The SUP meat at both fat levels was consistently more resistant to lipid oxidation than was the CON meat. The additional vitamin E had a greater anti-oxidant effect for the lean meat product. MA packaging in comparison to the oxygen-permeable foil over-wrap did increase lipid oxidation, the effect being most pronounced for the CON meat. A sensory panel considered the colour of the lean SUP meat during display as more attractive than that of lean CON meat, irrespective of packaging. A similar effect was observed occasionally for the relatively fat minced meat. These subjective findings were confirmed by objective assessment of colour. The stability of the colour of the MA packed meat was better than that of the oxygen-permeable foil-wrapped meat. Microbial growth patterns of enriched and control meat were similar. MA packaging retards the multiplication of mesophilic aerobic spoilage micro-organisms and Enterobacteriaceae.  相似文献   

10.
Pork muscle samples (M. longissimus dorsi) were obtained from pigs given one of four dietary treatments: (1) control diet; (2) supplemental iron [7-g iron (II) sulphate/kg feed]; (3) supplemental vitamin E (200-mg dl-α-tocopheryl acetate/kg of feed); and (4) supplemental vitamin E+supplemental iron. Muscle cores were packaged in polythene bags and placed in a retail refrigerated display cabinet at 5±1°C, under fluorescent light (1000 LUX) for up to 5 days. Samples were subjected to visual colour evaluation by a trained sensory panel (n=12) at 0, 1, 3 and 5 days. In addition instrumental L*, a* and b* values and drip loss were measured on each day of analysis. All samples became less red and browner over storage time in the refrigerated display cabinet. The vitamin E treated samples were more red and less brown compared with the other samples on successive days in the cabinet followed by the control, iron/vitamin E and iron treatments. The iron/vitamin E treatment was positioned midway between the vitamin E and iron treatments indicating that the vitamin E in the samples was effective in reducing the pro-oxidative effect of iron in inducing the brown metmyoglobin pigment development. Iron supplementation did not significantly (P<0.05) increase M. longissimus dorsi iron tissue levels, but had a detrimental effect on the visual sensory properties of the iron and iron/vitamin E treatment groups with greater metmyoglobin formation. Vitamin E appears to have promoted non-supplemental iron absorption in the vitamin E treated group without the detrimental sensory colour characteristics associated with ferrous sulphate supplementation. Drip loss increased in all samples during the course of the experiment with no significant (P<0.05) differences between the experimental groups. The panellists were able to differentiate the four experimental groups on each day of the study and were more effective in evaluating the colour quality of samples than instrumental assessment, i.e. the Hunter L* a* b* method.  相似文献   

11.
This study examined the shelf life of cured sausage under different packaging conditions from vitamin E supplemented pigs. One group (n=6) of crossbred pigs received a normal fattening diet containing 20 ppm α-tocopherol for 39 days before slaughter. Another group was fed a diet containing 410 ppm α-tocopherol during the same period. After slaughter, cured sausages were produced, packaged under three different atmospheric conditions, ripened for 4 weeks and then stored for 8 weeks (9?°C; 200 lux). The α-tocopherol content was recorded in the fat, liver, muscles and the sausage. TBARS, L*, a*, b* values and antioxidative capacity were evaluated in the sausage during storage. The results showed a transfer of vitamin E into tissues and sausage but no detectable effect on TBARS and colour stability. However, antioxidative effects of vitamin E were seen by provocation. Probably the effect of vitamin E in the sausage was masked by nitrite in the curing salt. The oxygen content of the packs had an influence on TBARS and colour stability.  相似文献   

12.
H. Larsen    F. Westad    O. Sørheim    L.H. Nilsen 《Journal of food science》2006,71(5):S407-S413
ABSTRACT:  The effect of packages with different oxygen transmission rates (OTR), different gas-to-product-volume (GP) ratios, and various levels of residual oxygen after packaging on the color stability of cooked ham exposed to commercial retail light conditions was studied. Sliced cooked ham was packaged in thermoformed packages with OTR of 0.04 and  0.06 mL O2/pkg × 24 h  and GP ratios of 2.6 and 4.1. After packaging, the packages were additionally divided into groups with 4 levels of residual oxygen ranging from 0.09% to 0.46%. The packaged ham was stored in darkness at 4 °C up to 33 d, and during the storage period samples were withdrawn and exposed to light for 2 d before instrumental and visual color evaluation. In order to maintain an acceptable color of this particular ham product when exposed to typical retail light conditions, the highest acceptable level of oxygen in the headspace of the packages was 0.15% oxygen at the time of illumination. This threshold level was independent of the storage time before light exposure. A residual oxygen level of below 0.15% just after packaging combined with the package with the lowest OTR  (0.04 mL O2/pkg × 24 h)  and the lowest GP ratio (2.6) was the optimal condition for maintaining the color of the tested ham product throughout the entire storage period.  相似文献   

13.
《Food chemistry》1999,67(2):163-171
The effect of increasing muscular content of vitamin E on colour intensity and stability of pork (both fresh and processed) was studied by feeding manipulation. Fresh pork was represented by loin chops and processed pork was represented by a dry cured fermented sausage (salame Milano) and raw cured ham (Parma ham). Dietary vitamin E was increased by feeding the animals with sunflower oil and α-tocopheryl acetate at 100 and 200 ppm. Chops were packed in oxygen-permeable film and in a protective atmosphere (80% O2 and 20% CO2) whereas salame Milano and Parma ham were packed under vacuum and in a protective atmosphere (85% N2 and 15% CO2). No differences in colour intensity or type were observed in relation to vitamin E content. Colour stability tests suggested, on the other hand, that higher vitamin E contents could be associated with slower myoglobin oxidation rates in fresh chops packed in a protective atmosphere. No effect of vitamin E on colour stability was observed in salame, probably because of the soft fat induced by sunflower oil. Significant differences among dietary groups were also not observed in Parma ham.  相似文献   

14.
The effects of dietary vitamin E supplementation on tissue α-tocopherol level and on the susceptibility of fresh and modified atmosphere-packaged beef on myoglobin and lipid oxidation were investigated. Charolais cattle, aged 32-44 months, were fed diets containing 75 (control, n=8) or 1000 mg (supplemented, n=8) α-tocopheryl acetate/kg feed/day for 111 days prior to slaughter. Following vacuum packaging, M. Longissimus lumborum and M. triceps brachii were aerobically packaged and held under refrigerated display (3°C) for 9 days or packaged under modified atmosphere (MAP; 20% CO(2): 80%O(2)) and held under refrigerated display (8°C) for 13 days under fluorescent light. α-tocopherol concentrations were significantly higher (P<0.05) in meat from the supplemented group than from the basal one. Whatever the measured colour characteristics (a*, R(630)-R(580),% MetMb), the vitamin E supplementation had a positive but non-significant effect on the rate of discoloration. But by visual assessment, essentially with MAP, a significant and positive effect of vitamin E supplementation was noted to lower discoloration (P<0.05). TBARS values were significantly lowered (essentially at the end of storage time for the two packaged modes) after an α-tocopheryl acetate-supplementation.  相似文献   

15.
The effect of addition of rapeseed oil (canola), CuSO(4) and vitamin E (all-rac-α-tocopheryl acetate) to pig diets on pork meat quality (lipid oxidation, colour and drip loss) was studied. Pigs were reared on ten different diets, either a control diet (no supplementation of rapeseed oil, CuSO(4) or vitamin E) or 6% rapeseed oil diets supplemented with CuSO(4) (0, 35 or 175mg/kg) and vitamin E (0, 100 or 200mg all-rac-α-tocopheryl acetate/kg). The natural content of vitamin E originating from feed ingredients amounted to 9-23mg vitamin E (α-tocopherol) per kg feed. Muscle vitamin E levels reflected the dietary intake and pigs fed the control diet had significantly lower levels than pigs fed rapeseed oil diets. The quality of fresh pork chops packed in air or in 80% O(2):20% CO(2) was followed during chill storage for 8 and 13 days, respectively. Colour, as measured by tristimulus colorimetry of pork chops packed in 80% oxygen atmosphere, was significantly improved with respect to redness when compared to chops packed in air, regardless of dietary treatment. The low vitamin E content in pigs fed the control feed significantly decreased a values and the oxidative stability of pork chops during chill storage compared to the other feeding groups. Packing of chops in a high-oxygen atmosphere increased lipid oxidation, especially in chops with low levels of vitamin E. Supplementation of rapeseed oil diets with 100 or 200mg vitamin E significantly decreased lipid oxidation of chill stored chops. Supplementation with CuSO(4) did not influence meat quality attributes (drip loss, colour stability and lipid oxidation) for any of the storage conditions.  相似文献   

16.
The combination of a muscle glycogen reducing diet or a standard diet (control group) with normal (80 mg/kg) and high vitamin E levels (500 mg/kg) and exercise immediately prior to slaughter was used on 56 pigs to investigate the influence on meat quality indicators (pH and temperature) and attributes (drip loss, colour and Warner–Bratzler shear force). The drip loss was reduced in M. longissimus dorsi, M. biceps femoris and M. semimembranosus in pigs given the muscle glycogen reducing diet compared with the control groups, the greatest effect was seen in exercised pigs. These results can be explained by an early post mortem reduction in glycometabolism in pigs fed muscle glycogen reducing diets rather than by an increase in ultimate pH. Noticeably, high dietary vitamin E level increased muscle glycogen stores by about 10% on the day prior to slaughter but not on the day of slaughter in both dietary groups compared with the low dietary vitamin E level, which in fact reduced rather than improved the water-holding capacity, especially in pigs fed the standard diet.  相似文献   

17.
The aim of this study was to find out whether concentrations of oxysterols in pig meat are affected by dietary polyunsaturated fatty acids and vitamin E. 48 growth-finishing pigs were fed diets with either palm oil or soybean oil and vitamin E concentrations of 15, 40 or 200 mg/kg. Concentrations of oxysterols were analyzed in fresh and heat-processed (180 °C, 20 min) meat (M. longissimus dorsi) and in boiled sausage prepared from meat and back fat of the animals. Concentrations of oxysterols in fresh muscle were below 5 nmol/g dry matter; they were independent of the dietary fat type and vitamin E concentration. Heating caused a large increase of oxysterol concentration (up to 55 nmol/g dry matter). This effect was reduced by increasing dietary vitamin E concentration but was independent of the dietary fat. Sausage from pigs fed soybean oil had higher concentrations of oxysterols than sausage from pigs fed palm oil; vitamin E reduced concentrations of oxysterols in sausage from pigs fed soybean oil, but not in sausage from pigs fed palm oil.  相似文献   

18.
The effect of extra vitamin E (2025 International Units animal-1 day-1) in the diet of bulls on the colour stability and lipid oxidation of lean mince was studied. Control and enriched diets were provided for the last 136 days before slaughter. Minces were prepared from M. biceps femoris and M. semitendinosus that had been stored for 2 months at -40 °C. Samples of minces with and without an ascorbic acid preparation (AAP) from control (CON) and supplemented (SUP) beef were packaged, half on trays over-wrapped with an oxygen-permeable foil and half in modified atmosphere (MA) packs (gas mixture applied: O2/CO2/N2, 75/20/5). Meats were displayed for 7days at 7 °C in an illuminated environment. The SUP meat was more resistant to lipid oxidation than the CON meat was. Also, the AAP consistently delayed lipid oxidation. A strong synergistic effect of both vitamins in this regard was demonstrated for the MA condition. MA packaging overall led to increased lipid oxidation. Colour measurements of SUP versus CON meats, without the AAP, generally failed to detect differences in redness values. The positive effect on the colour of freshly minced lean meats obtained by supplementation with vitamin E appeared to be almost nullified in minces made from previously stored frozen muscles. A sensory panel, however, still tended to judge the attractiveness of the colour of the SUP meat greater than that of CON meat. Addition of the AAP improved colour stability. Compared to the foil-overwrapped meat, colour was better retained in the MA packaged meat.  相似文献   

19.
Ripoll G  Joy M  Muñoz F 《Meat science》2011,87(1):88-93
The aim of this work was to determine the increase in the shelf life of modified atmosphere packaged fresh lamb meat due to the effect of dietary vitamin E and selenium supplementation on colour and lipid oxidation. 128 lambs were fed on a concentrate with standard levels of vitamin E (C), a concentrate enriched with vitamin E (V), a concentrate with sodium selenite (S) and a concentrate enriched with both vitamin E and sodium selenite (VS). The lambs were slaughtered at 27.3±1.45 kg LW, and chops stored on MAP for 7, 9, 11 and 13 days. CIELab colour and TBARs were studied on these days. Use of dietary vitamin E extended the shelf life a further 4 days from the commercial sell-by date in terms of lightness, hue angle, metmyoglobin formation and lipid oxidation. Selenium could be used to increase the lightness of meat without vitamin E supplementation in lambs' diets.  相似文献   

20.
Forty-eight castrated F2 offspring of Piétrain and Large White pigs were allocated to a 3×2 factorial design in order to study the interactive effect of halothane genotype (NN, Nn and nn) and pre-slaughter treatment (referred to as ’Experimental’ (EXP) and ’Commercial-like’ (COL) conditions; the latter involving short transportation, mixing unfamiliar pigs and slaughtering shortly after transport) on the qualities of cured-cooked and dry-cured hams. At 24 h post mortem, the hams were collected and assigned to cured-cooked (right ham) and dry-cured (left ham) ham processing. A sample of M. semimembranosus (SM) was collected before cooked ham processing, was used for chemical composition analysis, cured and then cooked at various temperatures. Cooking losses and compression tests were carried out after cooking on these SM samples. The water and collagen content of SM muscle was significantly higher in nn pigs compared with the two other genotypes. At all cooking temperatures (60, 65 and 70 °C), SM muscles from nn pigs showed higher cooking losses and instrumentally assessed toughness than the other genotypes, the heterozygous pigs being intermediate. The technological yield of cured-cooked ham processing was lower in nn, compared with NN and Nn animals. Cooked hams from nn pigs were drier, tougher, stringier and less smooth than NN and Nn pigs. The heterozygous pigs were similar to normal pigs for all texture characteristics with the exception of toughness for which they got a significantly higher score than NN pigs. The pigs slaughtered under the COL conditions had a better slice cohesiveness and a significantly lower dryness, than pigs slaughtered under the EXP conditions. The effect of HAL genotype on slice cohesiveness was significant only when pigs were slaughtered under the EXP conditions. Dry-cured hams from nn pigs showed significantly more visual defects, but were less tough, smoother and more fondant (softer) than NN and Nn pigs. The dry-cured hams from pigs slaughtered under the COL conditions had a better cohesiveness between muscles and a more intense yellow colour of fat than those from pigs slaughtered under the EXP conditions. COL pigs were also judged significantly less tough, smoother and more fondant than EXP ones. Overall, the effects of pre-slaughter treatment were small compared with those of the HAL genotype. The effects of HAL genotype on the sensory traits of cured-cooked ham were similar to those reported for fresh meat. However, the good textural characteristics of dry-cured ham processed from HAL positive pigs are somewhat surprising and need to be confirmed.  相似文献   

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