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1.
The present study was proposed to compare the effect that different types of stunning (TS) had on the quality of refrigerated meat from light lambs of the Spanish Manchega breed at 24 h and 7 days post-mortem. Lambs were electrically stunned (ESL; n = 10), using CO2 (GSL; n = 10) or slaughtered without previous stunning (USL; n = 10). Measurements on meat quality were carried out by evaluating pH, colour coordinates (L*, a*, b*), water holding capacity (WHC), cooking loss (CL), shear force (SF) and drip loss (DL). At 24 h post-mortem, no significant differences were found in any of the variables studied. However, at 7 days post-mortem, meat quality was affected by the different TS: pH, CL and DL were lower (P < 0.001) in the USL group and GSL obtained the lowest a* (redness) and b* (yellowness) values (P < 0.01) than in the other groups. Ageing of meat affected SF in the ESL group (P < 0.01), although there were no significant differences due to treatments at any of the ageing times.  相似文献   

2.
The aim of this study was to determine the effects of age on chemical composition and quality characteristics of the Arabian one-humped camel’s meat. Samples of longissimus thoracis (between the 10th and the 13th rib of the left side) were randomly collected from 21 Omani intact male camels of three different age groups: group 1 (1–3 years), group 2 (3–5 years) and group 3 (6–8 years). Samples were chilled (1–3 °C) for 48 h. Moisture, crude protein, fat and ash were determined on freeze dried ground muscle. Mineral contents were determined using an Inductively coupled plasma emission spectrometer (ICP). Meat quality including ultimate muscle pH, Warner–Bratzler shear force, sarcomere length, myofibrillar fragmentation index, expressed juice, cooking loss percent, and colour L*, a*, b* were measured using standard methods.

The moisture, protein, fat and ash ranged from 64.4% to 76.7%; 18.6% to 25.0%, 1.1% to 10.5% and 1.0% to 1.4% on dry matter basis, respectively. The Ca, Mg, Na, K, P, Cad, Cr, Ni, Pb, Co, Mo, Be and V ranged from, 9.2 to 46.6, 24.7 to 57.3, 104.7 to 257.0, 471.4 to 1053.0, 249.9 to 584.0, 0.005 to 0.024, 0.020 to 0.410, 0.016 to 0.187, 0.010 to 0.299, 0.010 to 0.018, 0.050 to 0.470, 0.005 to 0.030 and 0.013 to 0.141 mg/100 g on dry matter basis, respectively. The percentage of protein decreased and that of fat increased with increasing camel age. The ultimate pH, shear force, sarcomere length, fragmentation index, expressed juice, cooking loss, lightness (L*), redness (a*) and yellowness (b*) ranged from 5.46 to 6.64, 4.25 to 17.82, 0.96 to 2.50, 55.91 to 94.81,19.50 to 33.63, 13.18 to 29.88, 27.86 to 43.21, 10.46 to 22.81, and 4.63 to 10.11, respectively. Muscles of younger camels (group 1) had significantly (P < 0.05) lower shear force value, ultimate pH and higher sarcomere length, fragmentation index, expressed juice, cooking loss, and lightness color (L*) by 48%, 3.4%, 43%, 25%, 28%, 14%, and 16% than those collected from older camels (group 3), respectively. Values of middle age camels (group 2) camels were in-between. This study confirmed that camel meat is healthy and nutritious as it contains low fat as well as being a good source of minerals. Age is an important factor in determining meat quality and composition.  相似文献   


3.
The use of conventional concentrates in the supplementation of grass-based fed lambs may induce improvements in growth performance and/or carcass quality but may be disadvantageous in fatty acid profile of tissues, with a negative impact in some nutritional indexes. The objective of this trial was to evaluate the effects on growth performance, carcass and meat quality of using unprotected, unsaturated fat as a supplement for grass-fed based lambs. Twenty-four Merino Branco ram lambs raised on pasture, were supplemented with corn whole grain plus sunflower meal or corn whole grain plus expanded sunflower seed, from 20 to 30 kg live weight. The supplement had no effects on growth performance, carcass quality traits, or meat pH, colour estimates (L*, a*, b*), water-holding capacity, shear force and sensorial attributes. However, lambs supplemented with expanded sunflower seed showed higher proportions of cis-9, trans-11 octadecadienoic acid and trans-vaccenic acid in intramuscular and subcutaneous fat, showing that the inclusion of unprotected lipids in lambs diet was effective in preventing the reduction of rumenic acid (C18:2 cis-9, trans-11) that occurs when conventional concentrates are used as a supplement.  相似文献   

4.
Springbok is the most extensively cropped game species in South Africa. The effects of age (adult, sub-adult, lamb), gender and production region on the physical attributes (pH24, cooking and drip loss, Warner Bratzler shear force and colour) were determined using samples of the M. longissimus dorsi (LD) muscles of 166 springbok. Stressed animals had a higher (P < 0.05) pH24 (6.3 ± 0.07), as observed in the meat originating from the Caledon region. This meat had lower (P < 0.05) cooking loss (27.2 ± 0.62%) and drip loss (1.8 ± 0.08%) values in comparison to meat originating from the other regions. Inverse correlations were noted between pH24 and drip loss (r = −0.26, P < 0.01) and cooking loss (r = −0.42, P < 0.001). Shear force values (kg/1.27 cm diameter) correlated positively (r = 0.25, P < 0.01) with pH24. Age-related effects on tenderness were small in comparison with pH24 effects. CIELab colorimetric values were typical of game meat and venison (L* < 40, high a* and low b* values). It was noted that pH24 correlated negatively (r = −0.51, P < 0.001) and positively (r = 0.33, P < 0.001) with the hue-angle and the chroma value of colour, respectively. Springbok originating from Caledon had a significantly (P < 0.05) higher a* value, indicating meat to be more red with higher colour saturation.  相似文献   

5.
Forty-eight bulls were transported by road in groups of eight for approximately 30 min, 3 or 6 h in two replicates. After slaughter, steaks from the longissimus dorsi thoracis of all transported animals were analysed in terms of pH, water-holding capacity, myoglobin concentration, texture at 7 and 14 days of ageing (compression and Warner-Bratzler analyses) and colour of the same surface of meat cut at 24 h post-mortem and allowed to bloom for 24 h and 7 d (L*a*b*, chroma and hue). The myofibrillar resistance of the meat from animals transported 30 min was significantly greater at 20% compression (P<0.05). The maximum load and a*b* and chroma were all lower for meat aged 14 days.  相似文献   

6.
The effects of different proportions (0%, 10%, 20%, 30%, 40%) of washed mechanically deboned chicken meat (WM) as a substitute for hand deboned chicken meat, on the physicochemical and sensory characteristics of chicken nuggets were evaluated. The addition of WM increased fat content, but it was only significant (P < 0.05) when 40% of WM was added, whereas the protein content was significantly (P < 0.05) reduced as from 20%. Significant differences (P < 0.05) were found in L*, a* and b* values with different proportions of WM, however, these differences were evidently not discerned as shown by the no significant differences (P > 0.05) in ΔE* color scores. The addition of WM did not affect (P > 0.05) sensory attributes of chicken nuggets. From a technical viewpoint, up to 40% WM could be incorporated into nugget formulation instead of hand deboned chicken meat without affecting sensory attributes of the product. Minor changes in composition were observed but they were probably not detrimental to the product.  相似文献   

7.
Kim YS  Yoon SK  Song YH  Lee SK 《Meat science》2003,63(4):509-513
A total of 1278 head of Hanwoo (Korean native cattle) slaughtered over four seasons were used to evaluate the effect of season on color characteristics of beef longissimus dorsi (LD) muscle. CIE L*, a*, b*, C* values and hue angle were significantly lower (P<0.05) in cattle slaughtered in the winter season. Meat color was darker in the winter than in the spring and autumn seasons. The L* values among three average daily temperature (Ta) categories were different (P<0.05) in order of: [5 °CTa<25 °C] > [Ta25 °C] > [Ta<5 °C], indicating that the meat color of cattle slaughtered at Ta<5 °C was darker. The a*, b*, C* values and hue angle were significantly lower (P<0.05) in cattle slaughtered at Ta<5 °C. Season at slaughter is of great importance for meat color. Namely, meat color of Hanwoo beef was influenced by environmental temperature. Overall, cattle slaughtered in the winter season of Ta<5 °C produced beef with more undesirable meat color properties.  相似文献   

8.
Zhang X  Kong B  Xiong YL 《Meat science》2007,77(4):593-598
Lactobacillus fermentum was substituted for nitrite to produce cured pink color in a Chinese-style sausage. Treatments included inoculations (104, 106, and 108 CFU/g meat) followed by fermentation at 30 °C for 8 h and then at 4 °C for 16 h. Control sausage (with sodium nitrite, 60 mg/kg meat) was cured at 4 °C for 24 h without L. fermentum. The UV–Vis spectra of pigment extract from L. fermentum-treated sausage were identical to that of nitrosylmyoglobin (NO-Mb) formed in nitrite-treated control. The NO-Mb concentration and the colorimetric a* value of sausage treated with 108 CFU/g meat of L. fermentum essentially replicated those in nitrite-cured meat. Free amino acid content in sausage treated with L. fermentum was greater and the pH slightly lower compared with the nitrite-cured control sample. This study showed that L. fermentum has the potential to substitute for nitrite in the sausage production.  相似文献   

9.
The effects of oxygenation and thermal treatment (internal temperature, Ti: 45, 60, 75°C) on the colour and some colour related physical and biochemical properties of beef longissimus dorsi (LD) muscle, both normal (pHu5.6) and DFD (pHu>6.6), were studied. The colour components (L*, a*, b* values) for the raw and heated LD, both before and after oxygenation, were instrumentally and sensorily evaluated. The colour of raw and heated (60°C) DFD beef before and after oxygenation differed significantly from the normal meat and contained more native muscle pigment (TMP). pH also influenced the depth of the oxygenated layer, specific activity of cytochrome c oxidase (SACCO) and the amount of oxygen consumed. An increase in internal temperature was usually accompanied by a lower SACCO and a significant decrease of TMP, as well as a change of all colour parameters. Oxygenation of the raw and heated slices (except at 75°C) of both types of meat led to higher L*, a* and b* values.  相似文献   

10.
The effect of genotype on meat ultimate pH, colour and tenderness was studied in 3 experiments involving 436 lambs. The lambs were sired by a selection of Texel (T), Poll Dorset (PD), Border Leicester (BL) and Merino (M) rams, crossed with Border Leicester × Merino (BLM) and Merino (M) ewes giving 6 genotypes (T × BLM, PD × BLM, T × M, PD × M, BLM and M × M). In experiment 1, pH data were obtained for 4 muscles (M. Semimembranosus (SM), M. Biceps femoris M. Semitendinosus and M. Longissimius thoracis et lumborum (LL)) from 198 carcasses representing two sexes (104 cryptorchid males, 94 ewes). There were significant differences for pH between genotypes in both sex groups. BL × M and M × M lambs tended to have higher pH values than the other genotypes.

In experiment 2, meat pH, colour using a chromameter, and tenderness data were obtained for 186 lambs representing two sexes (101 cryptorchid males, 85 ewes). There were few significant differences between genotypes for the various meat quality traits amongst the ewes. The PD × BLM ewes had a significantly lower (p < 0.05) pH than the BL × M ewes for the LL and SM muscles.

The BL × M crypt orchids had a higher LL muscle pH (p < 0.05) than the PD × BLM cryptorchids with other genotypes being intermediate. There were no significant differences between the genotypes for muscle shear force values. Within experiment 2, LL samples were taken from an additional 52 cryptorchid carcasses these being from 3 specific Poll Dorset sires (experiment 3). One of these sires (sire 3) was suspected of carrying a gene for increased muscling. Sire had a significant effect (p < 0.05) on shear force values, cooking loss and L* colour values, but not a* or b* colour values or pH. Sire 3 progeny had significantly (p < 0.001) tougher LL muscles than those from the other 2 sires. Sire 3 also had the lowest L* values, but was intermediate for cooking loss. There was no significant sire effect on LL area at the same carcass weight, but boneless loins from the progeny of Sire 3 were significantly (p < 0.05) heavier.

In a fourth experiment, meat colour was measured at three sites (LL, diaphragm and M. Obliquus externus abdominis) on 86 cryptorchid carcasses 24 hr post-mortem. There was little association between L*, a* and b* values measured at the different sites.  相似文献   


11.
A study on the effect of rearing system on tissue composition of principal joints and chemical–physical traits of meat and subcutaneous fat, was carried out on a local pig breed. A total of 78 Nero Siciliano pigs was used; 41 pigs were reared in woods, 37 pigs were reared in pens and fed a commercial diet. Weight at slaughter was 101.9 and 88.2 kg for indoor and outdoor pigs, respectively. Means were estimated at 77 kg of live weight. At ham dissection outdoor-pigs showed higher percentages of lean (58% vs. 55%) and lower subcutaneous fat (31% vs. 34%). In Longissimus lumborum outdoor-pigs showed a higher intramuscular fat percentage (4.3% vs. 3.3%), a lower protein content (22.2% vs. 23.4%), and higher free water (9.6 vs. 7.9 cm2). Outdoor pigs produced more light (L*=50 vs. 46.7) and more yellow (b*=5.84 vs. 4.88) meat. Subcutaneous fat of outdoor pigs showed higher percentages of MUFA (53.3% vs. 47.2%) and lower percentages of PUFA (10.85% vs. 14.45%), no differences were found for n−3 PUFA. Outdoor-pigs had lower atherogenicity (0.48 vs. 0.53) and thrombogenicity (1.03 vs. 1.21) indices.  相似文献   

12.
The objective of this study was to evaluate the use of digital images (DI) to estimate CIE L*a*b*, hue angle and chroma of beef, as compared to a colorimeter (CM). Loin samples from 21 steers finished with high-grain diets were displayed under retail-simulated conditions. Color readings were obtained from 63 cores covering the full spectrum of discoloration in beef. CIE L*, a*, and b* were measured with a surface-reflectance CM. Red, green and blue (RGB) values were obtained from DI and sequentially transformed to XYZ and CIE L*a*b* color space. Hue angle and chroma were calculated from a* and b* values. Regressions of CM on DI for a*, hue angle and chroma had R2 values of 0.93 and above. Average color difference () between the predicted and the actual CM L*, a*, and b* values for 13 samples that were not included in the regressions was 1.57, below reported thresholds of detection for 50% of observers. Color readings from DI could be used to accurately predict color coordinates measured by CM, especially a*, hue angle and chroma. Use of digital imaging could become a practical tool to detect changes in beef color and other muscle foods.  相似文献   

13.
The surface decontamination of meat by steaming and by lactic acid prolongs its shelf life. Possible changes of colour were evaluated by reflectance spectrophotometry and video image analysis (VIA). Reflectance spectra were measured using a D65 source and CIELab values L*, a* and b* were calculated together with ratios of the different myoglobin forms (red, oxy, met). The same samples were evaluated by video image analysis (software LUCIA). Steaming and spraying with lactic acid increased slightly the lightness (L*) of the meat surface. Coordinate a* (redness) decreased slightly after the decontamination treatment. This was confirmed by VIA; brightness increased and red-ratio r decreased. Both methods, i.e. reflectance spectrophotometry and VIA, reflect the colour changes in a similar way. The main advantage of reflectance spectrophotometry was its higher sensitivity and the possibility of direct calculation of the ratio of the haem pigment forms. However, video image analysis allows analysing of different particles in the image and this method is therefore a suitable tool for monitoring the changes of the surface appearance.  相似文献   

14.
Color evaluation of carbon monoxide treated porcine blood   总被引:1,自引:0,他引:1  
The stability of liquid porcine blood, treated with carbon monoxide (CO) at different pH values (7.40, 6.70, and 6.00) up to its complete saturation, was studied. Lowering the pH from 7.40 to 6.70 resulted in a decrease in the amount of CO necessary to obtain 100% carboxyhemoglobin. Further pH lowering to 6.00 did not result in additional reduction in the amount of gas. During 4 days of refrigerated storage CO treated liquid blood maintained, at every pH, a more stable and attractive red color than fresh blood, which was a result of an increase (P<0.05) of a* (redness) and b* (yellowness) values and no variation (P>0.05) on L* (lightness) value. Hue (h*) and chroma (C*) decreased in the untreated blood but not in the CO-treated blood. The results indicate that blood saturation with CO yields a product having greater potential for use in meat products without compromising its visual appearance.  相似文献   

15.
The relation between measurements of colour made in the m. adductor (AD) at 45 min or 20 h post mortem and the quality, assessed subjectively in terms of colour and waterholding capacity, of the m. longissimus (LD) in the loin was examined. The study used data from 100 pig carcasses exhibiting a wide range of meat quality from extreme PSE (pale, soft and exudative) to extreme DFD (dark, firm and dry). The subjective assessments were confirmed by objective measures of paleness (reflectance) and waterholding capacity (drip loss in storage) in the LD. Lightness (L*) measured at 20 h post mortem in the AD was the best potential predictor of loin muscle quality, explaining 59% of the variation in subjective and objective quality measures. Comparable measurements at 45 min post mortem explained between 21% and 44% of the variation. The equation that described the relation between AD Lightness (L*) and subjectively assessed LD quality was derived. This could be used to transpose the AD L* values from a population of slaughtered pigs into nominal subjective scores for the LD, allowing the frequency of the five subjective quality groups (extremely DFD, slightly DFD, normal, slightly PSE, and extremely PSE) in the population of carcasses to be defined.  相似文献   

16.
The effect of dietary protein and gastrointestinal (GI) parasitism on growth and meat quality of lambs was assessed using 60 animals. The lambs were randomly allocated to one of three treatment groups (n = 20): group A, which served as control, group B that was regularly treated with albendazole and group C, which was given supplementary feeding with dietary protein. The three groups of lambs grazed into a pasture (Lolium perenne), which was contaminated with L3 larvae of GI nematodes. Lamb growth and condition score were assessed at 21-day intervals. After 126 days grazing all lambs were slaughtered and their carcasses were assessed for conformation and fatness and their ultimate pH was measured. Four carcasses from each group were randomly selected for meat quality measurements including physical analysis as well as colour, moisture, total fat, protein content and fatty acid composition. Parasitic challenge was assessed by means of faecal egg counts of lambs, pasture larvae and numbers of adult nematodes in the GI tract of lambs at slaughter. Growth rate of group B was higher (P < 0.01) than that of group A and resulted in significantly (P < 0.01) heavier carcasses. The produced carcasses had similar fatness, but differed significantly (P < 0.05), in their conformation; carcasses of group C scored higher than either those of group B or group A, respectively. There was a significant difference in the colour attributes (L*) with group A being significantly lighter (P < 0.05) and in pH (P < 0.01); Group B had the highest values. Carcasses of group C had the highest (P < 0.05) amounts of intermuscular fat compared to those of group B and A, respectively. The proportion of C16:1n-7 and C18:2n-6 was higher (P < 0.05) in subcutaneous fat tissue whereas the proportion of C18:0 was higher (P < 0.05) in muscle tissue. In conclusion, the present results showed that the increased protein content in the diet of growing lambs, grazing on a pasture infected with GI nematode larvae, resulted in the production of acceptable carcasses.  相似文献   

17.
Quality aspects of sliced dry-cured beef “Cecina de León” preserved in vacuum and gas mixtures (20%/80% CO2/N2 and 80%/20% CO2/N2) were studied. The evolution of microbiological, physicochemical and sensory parameters were analysed during storage (210 days) at 6 °C. Although microbial counts at 60 days of the gas-packaged samples were lower than the vacuum-packed ones, they were never higher than the spoilage limit (7 log ufc/g). A slight increase (p < 0.05) in pH was observed throughout storage of “Cecina de León” packaged under vacuum and in gas mixtures. However, a decrease (p < 0.05) in aw was observed during storage of “Cecina de León” packaged under vacuum but aw did not vary (p > 0.05) during storage in the gas-packaged samples. No changes were observed (p > 0.05) in lightness (L*), redness (a*) and yellowness (b*) in vacuum and gas packaged samples during storage. However, sensorially evaluated colour showed lower values in gas packaged samples during 30 days storage. This difference was decisive in establishing the shelf-life of “Cecina de León” slices preserved in gas mixtures (20%/80% CO2/N2 and 80%/20% CO2/N2). Therefore, from a microbiological point of view, gas mixtures are more effective in extending the shelf-life of “Cecina de León” slices. It is concluded that vacuum packaging allows longer storage than gas-packaging as it maintains a good visual appearance of “Cecina de León”, the main parameter in consumers’ perception of meat quality.  相似文献   

18.
We hypothesized that the lightness of Japanese beef was related to the concentration of heme iron. In Experiment 1, six Japanese Black heifers were allotted randomly to one of three treatment groups: a basal concentrate ration (40% flaked corn) or the same diet and either 2 kg/d wheat bran or 0.5 kg/d green tea. After feeding the diets for 174 d, the cattle were slaughtered and the M. longissimus thoracis, M. semimembranosus, and M. gluteus medius were sampled for meat color, iron, and lipid content. The iron content of the M. semimembranosus from the tea-fed cattle was lower than in M. semimembranosus from the control cattle, and a* (redness) and √(a*2+b*2) (saturation) values were lower in M. semimembranosus from bran- and tea-fed cattle than in control cattle. Treatment main effects (across muscles) indicated that inclusion of tea in the diet increased intramuscular lipid and reduced the muscle iron content. There was a significant negative correlation (r2=0.79) between muscle iron content and L* value (lightness). For Experiment 2, the effect of beef breed type on meat color and iron content of M. longissimus thoracis was investigated using stored meat samples from six breeds from a previous fattening experiment done under a high nutritional plane. Muscle iron content was significantly lower in Japanese Black cattle than in Japanese Black × Holstein or Japanese Black × Japanese Black/Holstein. There was no relationship between muscle iron content and intramuscular lipid content (r2=0.001). In Experiment 3, samples of M. longissimus dorsi were obtained from 17 Wagyu crossbred and 3 Angus crossbred cattle fed a corn concentrate diet in the USA for 148 d. Iron content of the M. longissimus thoracis from Japanese Black and Japanese Brown × Holstein cattle fattened in Japan was significantly less than the iron content of M. longissimus dorsi from cattle raised in the USA. Overall, the data indicate that it is possible to lower muscle iron, and lighten muscle color, by feeding green tea to Japanese cattle; also, there may be a genetic basis for the lower iron, and lighter color, of beef produced in Japan.  相似文献   

19.
Effect of dietary oregano oil supplementation on lamb meat characteristics   总被引:1,自引:0,他引:1  
The effect of dietary oregano essential oil supplementation on lamb meat characteristics was investigated. Eight male and eight female Chios lambs were divided into two equal groups. The first group was fed with the control diet consisting of concentrated feed and alfalfa hay, whereas the second group consumed the same diet, the only difference being that the concentrated feed was uniformly sprayed with oregano essential oil (1 ml/kg). Duration of the experimental period was two months.

No differences were observed after oregano essential oil supplementation in final body weight (kg), body weight gain (g) and carcass yield (%). Tenderness of longissimus thoracis muscle, expressed as sarcomere length and shear force value, was not influenced by the treatment, whereas pH and colour parameters (yellowness–redness) appeared to increase (P < 0.05). Moreover, results showed that dietary incorporation of oregano essential oil exerted strong antioxidant effects retarding lipid oxidation (MDA formation) in meat during refrigerated and long-term frozen storage (P < 0.001).  相似文献   


20.
Tenderness is an important meat quality parameters and the use of high power ultrasound to disrupt muscle structure may prove effective for reducing both myofibrillar and collagenous toughness. The experiment was carried out with Longissimus lumborum et thoracis and Semitendinosus muscles from 3 to 4 year old steers. Uncooked beef samples (60 × 40 × 20 mm) were treated with high power ultrasound (24 kHz, 12 W/cm2) for up to 240 s, and aged for up to 8.5 days before evaluation of pH, drip loss, cook losses Warner–Bratzler shear (WBS), compression hardness, and colour. Ultrasound treatment significantly reduced WBS force and hardness, but significantly increased pH. Ageing significantly reduced hardness and WBS force, but there was no significant interaction between ultrasound treatment and ageing time. Ultrasound treatment did not affect any of the colour parameters (L*a*b*, chroma and hue) but the ageing time significantly increased the lightness, chroma and hue. There was no significant effect of ultrasound treatment on drip loss, but it did significantly reduce the cook and total loss. During ageing, cook loss and total losses significantly increased. The results suggest that high power ultrasound is capable of reducing objective texture measurements of beef without compromising the other quality parameters investigated.  相似文献   

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