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1.
Ham steaks, loin chops, bacon slices, shoulder roasts and sausage patties fabricated from three muscle quality groups were utilized to evaluate the effects of muscle quality on palatability and cooking properties. Irrespective of muscle quality (pale, soft, exudative (PSE) versus normal versus dark, firm, dry (DFD)) all pork cuts evaluated were well within the acceptable range in palatability. In addition, results indicated that inherent muscle quality differences were of little relevance to the eating quality of pork. However, meaningful differences in cooking losses were observed from loin chops and bacon slices.  相似文献   

2.
Thirty Santa Gertrudis bulls (approximately 15-18 months old) were slaughtered, dressed and split into siides. The right side of each carcass was electrically stimulated (ES) with seventeen impulses (1·8s impulse duration; 1·8s interval between impulses) of 550 V (AC) and 5 A while the left side served as a non-stimulated control (not-ES). At 24h post morten, USDA quality and yield grade data were obtained from each side. On the second day post mortem, all sides were fabricated and strip loins, top sirloin butts and ribeyes were obtained from each side for post-mortem ageing and blade tenderisation studies. Steaks were removed after a post-mortem ageing period of 4 or 18 days and before (not-BT) or after blade tenderisation (BT) for sensory panel evaluations or shear force determinations. ES sides had more youthful lean maturity (P < 0·0001), higher marbling (P < 0.·002), higher USDA quality grades (P < 0·0.0001) and finer-textured lean (P < 0·002) than did not-stimulated (not-ES) sides. ES significantly improved (P < 0·05) palatability traits in two of twenty-four comparisons; BT significantly improved palatability traits in twelve of twenty-four comparisons and 18-day post-mortem ageing significantly improved palatability traits in seven of twelve comparisons. No significant reductions (P < 0·05) in shear force values were observed for steaks from ES versus not-ES sides while significant reductions (P < 0·05) were observed for steaks from BT versus non-BT cuts (four of six comparisons) and for steaks from cuts aged for 18 versus 4 days (ten of twelve comparisons). BT and 18-day post-mortem ageing were more effective for increasing palatability or for decreasing shear force requirements than was ES; however, ES greatly improved lean colour of meat from bulls.  相似文献   

3.
Two experiments were conducted to determine the effects of cryogenic chilling on the carcass shrinkage, meat quality, bacterial condition and palatibility of pork. In experiment I, pork sides were chilled at 1°C (n = 20), or immersed in liquid nitrogen (LN) for 1 or 3 min prior to placement in a 1°C cooler. Muscle temperature in the loin was significantly lower at 2 and 6 h post mortem in treated compared to control sides, and loin muscle pH was higher (P < 0·05) at 6 h post mortem in sides immersed for 3 min in LN. Carcass side shrinkage was reduced from 29·3 g kg(-1) in control sides to 20·9 and 13·5 g kg(-1) in sides dipped in LN for 1 and 3 min. Chilling treatment had no significant effect on the survival of mesophilic bacteria on carcass sides, on meat colour, drip loss, protein solubility or sarcomere length, but sides dipped for 1 min in LN has a higher muscle shear value than control sides. In experiment II, carcass sides from halothane positive (H+) and negative (H-) pigs were conventionally chilled (n = 49), immersed in LN for 3 min (n = 23), or electrically stimulated and chilled in LN for 3 min (n = 26). Similar results for temperature, pH, colour, protein solubility and drip loss in loin muscle were found to those in experiment I. Laboratory taste panel results showed that chilling treatment had no effect on palatability. Genotype produced meaningful differences in most palatability attributes with H+ pigs having less tender, less juicy and less desirable flavour than pork from H- pigs. Laboratory studies with inoculated fresh muscle slices showed that a 3 min immersion in LN resulted in a 10-fold reduction in the aerobic spoilage pseudomonads, but effects upon other spoilage bacteria and potential human pathogens were less pronounced. It was concluded that cryogenic chilling using LN reduced carcass shrinkage during cooling, but had no consistent effects on meat quality, palatability or bacterial numbers on the carcass. In contrast, genotype had a significant effect on most pork quality and palatability attributes.  相似文献   

4.
The sensory characteristics of pork chops from bone-in loins and Boston butts (n = 65 each) were affected little by primal loin and the butt packaging method (paper wrap, vacuum pack and gas flush) and storage time (7, 10 and 14 days) under industry conditions. However, loin chops fabricated from vacuum-packaged loins after 14 days of storage had less (P < 0·05) discoloration and two-toning than chops fabricated from other loins. All loin chops were placed in retail display and overwrapped with a polyvinyl chloride film after fabrication at each storage time. Vacuum-packed butts stored for 10 and 14 days produced chops with less discoloration and two-toning, and higher overall appearance scores (P < 0·05) compared to chops from paper-wrapped or gas-flushed cuts. Vacuum-packaging resulted in higher quality retail cuts than paper-wrapped or gas-flushed packaging. Thus, it is recommended that the pork industry and retail distribution system utilize vacuum-packaging as the primary method to store and ship fresh pork before retail sale.  相似文献   

5.
This study was designed to evaluate the visual and palatability characteristics of boneless cured hams and fresh loin chops from pigs fed diets containing 0, 5, 10 or 20 ppm of the phenethanolamine, ractopamine hydrochloride (RAC). Sixty pigs were blocked by starting weight and randomly assigned to pens (four pigs/pen) within each of three blocks. Treatments were then randomly assigned to pens (six pens of the 0–ppm level and three pens each for the 5, 10 and 20 ppm RAC levels). Animals were slaughtered by weight block after approximately 48 days on trial. Fresh pork hams and loin sections (10–14th rib) were removed from the right side of the carcasses for subsequent analysis. Boneless hams were manufactured using commercial curing procedures. RAC had no effect (P > 0.05) on visual or palatability attributes of ham slices or boneless loin chops. Moisture content of the longissimus muscle from RAC treatments was lower (P < 0.05) than controls; however, this difference was small. These results indicate that RAC had no affect on the visual or palatability characteristics of boneless cured and smoked hams or fresh boneless pork loin chops.  相似文献   

6.
Forty-eight fresh hams and bellies were obtained from 24 market weight hogs (x = 94·5 kg) of which twelve were electrically stimulated (ES) by pulsing current immediately after exsanguination. The left side of each non-stimulated (NS) carcas was fabricated after conditioning for 3h post mortem at 17°C (NS hot-processed). The left sides of ES carcasses were fabricated 1 h pm. The right sides were fabricated following a 24 h cooler chill at 2°C (conventionally chilled: CP). Hams from ESCP carcasses had higher (P < 0·05) smokehouse yields than hams from NS carcasses. Hams that were hot-processed had higher smokehouse yields than the NSCP hams. Time of fabrication (1, 3 or 24h post mortem) did not affect smokehouse yields. Conventionally chilled bellies obtained from ES carcasses showed higher (P < 0·05) residual nitrite levels than those front electrically stimulated hot-processed (ESHP) carcasses. No differences were found for residual nitrite levels in the non-electrically stimulated sides. Panelists were unable to detect any sensory differences from the bacon strips. Sensory scores of ham slices were more juicy for non-stimulated hot-processed carcasses (NSHP) than those from ESHP carcasses. Panelists found the ham slices from NSCP carcasses to be more tender (P < 0·05) than those from electrically stimulated cold-processed (ESCP) carcasses. Results from this study clearly indicated that hot-processing of pork can provide hams and bellies that are acceptable for the production of cured hams and bacon of comparable quality and yield to those currently being produced under conventional processing methods.  相似文献   

7.
Alternate right or left sides of 90 carcasses were randomly selected and chilled at -70°C for 5 h, held at +16°C for 4 h and held at 1°C for 15 h (rapid chill-RC). The remaining sides were chilled at -7°C for 24 h (conventional chill-CC). Physical measurements and USDA quality grade data were obtained at 24 h post mortem and palatability samples were collected at 3-5 days post mortem. RC sides had 0·9% less shrinkage (P < 0·05) at 24 h post mortem when compared to paired CC sides. Beef sides that were given the RC treatment had a darker, softer lean (P < 0·01) and received higher marbling scores (P < 0·01) at 24 h post mortem than did CC sides. Loin steaks from RC sides had longer sarcomeres, less shear resistance and higher sensory panel tenderness ratings. It may be possible to rapidly chill carcasses with less carcass shrinkage and with no detrimental effects on USDA quality grade or on beef palatability.  相似文献   

8.
Fifteen slaughter cattle from five groups (Charolais crossbred bulls, Brahman crossbred steers, Holstein steers, mixed-Exotic crossbred heifers and Hereford-Angus crossbred steers) were randomly selected from a commercial feedlot. Time-on-feed was 108, 114, 102, 108 and 145 days for the aforementioned groups, respectively. Carcasses from Charolais crossbred bulls had the highest percentage yield of chuck and round, but the lowest percentage yield of loin; hereford-Angus crossbred steers had the lowest percentage yield of round and Holstein steers had the lowest percentage yield of rib. Carcasses from Charolais crossbred bulls had the highest percentage yield of major retail-ready subprimals and lean trim, Hereford-Angus crossbred steers had the highest percentage yield of fat trim and Holstein steers had the highest percentage yield of bone from the major wholesale cuts. Mean percentage yields of closely trimmed, boneless retail cuts were highest for carcasses from the bulls and lowest for carcasses from the Hereford-Angus steers. Although Holstein steer carcasses had less fat trim than Brahman-crossbred steers mixed-Exotic heifers, this advantage was largely offset by their higher percentage of bone. Loin steaks from carcasses of Charolais crossbred bulls, Holstein, mixed-Exotic heifers were comparable (P > 0·05)with those of Hereford-Angus steers for shear force and sensory panel tenderness ratings. However, loin steaks from carcasses of Brahman-crossbred steers had significantly higher (P < 0·05) shear force values (least tender) and lower (P < 0·05) tenderness and overall palatability ratings. No diffeerences (P > 0·05) were found for flavor desirability of loin steaks among any of the groups. For bottom round steaks, Hereford-Angus steers received the highest palatability ratings while those from Holstein steers received the lowest palatability ratings.  相似文献   

9.
Seventy-five steers (9 to 12 months of age) of Angus (n = 25), Brahman (n = 25) and Brahman × Angus (n = 25) breed-types of known history were fed a high-energy diet and five steers from each breed-type were slaughtered after 0, 56, 112, 168 and 224 days on test. At seven days post mortem, the left side of each carcass was fabricated and eight major primals or subprimals were obtained. Steaks were removed from the shoulder clod, strip loin, tenderloin, top sirloin, knuckle, top round, bottom round and eye of round for Warner-Bratzler shear (WBS) determinations and from the strip loin and bottom round for sensory panel evaluations. Steaks from Angus and Brahman × Angus steers were generally more tender than steaks from Brahman steers. Tenderness of steaks from steers of the three breed-types responded to time-on-feed differently: (a) steaks from Brahman steers improved (P < 0·05) in tenderness with increasing time-on-feed for all muscles except the M. psoas major (tenderloin); (b) with the exception of the M. longissimus muscle (strip loin), the tenderness of steaks from Angus steers did not change (P > 0·05) as time-on-feed increased and (c) for the Brahman × Angus steers, five of the ten muscles studied improved (P < 0·05) in tenderness with increasing time-on-feed. 'Acceptable' tenderness (WBS values of less than 4·5 kg) for most of the muscles was achieved at feeding periods from 112 to 224 days for Brahman, from 0 to 56 days for Angus and from 56 to 168 days for Brahman × Angus.  相似文献   

10.
Pork loin chops of High, Intermediate and Low intramuscular fat were trimmed free of subcutaneous fat and then packaged and stored in polyvinyl chloride (PVC) film for 0-6 days or in high oxygen barrier (HOB) film for 0-28 days at 4°C ± 1°C. In general, marbling group had no (P > 0·05) effect on the aerobic plate count (APC) and did not result in major differences in the distribution of types in the microflora of pork loin chops. During storage, Pseudomonas spp. became dominant in the microflora of PVC-wrapped chops while Lactobacillus spp. became dominant in the microflora of chops stored in HOB film. Of the sensory characteristics examined, mean surface discoloration and mean overall appearance scores of chops of Low intramuscular fat stored in HOB film were usually lower (P < 0·05) than those of chops of Intermediate and High intramuscular fat. In contrast, marbling group usually had no significant effect on mean surface discoloration and mean overall appearance scores of chops packaged in PVC film.  相似文献   

11.
The ability to perform Warner–Bratzler and slice shear force on the same beef top loin steak was investigated. Three, 2.54-cm steaks from top loins (n = 99) were allotted to either Warner–Bratzler only (WBS), slice shear force only (SSF), or Warner–Bratzler and slice shear force (WBS/SSF). Steaks were thawed at 2 °C for 48 h prior to cooking. Steaks were cooked to 71 °C using a conveyor convection oven and allowed to cool at room temperature for a minimum of 4 h. Steaks allotted to WBS used six 1.27-cm cores and steaks allotted for WBS/SSF used four cores. Steaks allotted to SSF and WBS/SSF used one, 1 cm × 5 cm slice. Correlations among WBS and SSF for all steaks ranged from 0.49 to 0.69 (P < 0.0001). When correlations were generated for steak location within the top loin, the relationships among WBS and SSF performed in the same steak ranged from 0.53 to 0.70 (P < 0.05). These results indicate that it may be feasible to conduct WBS and SSF on the same top loin steak, and that the steak taken 2.54 cm from the 13th rib is the optimal location for this combination of procedures.  相似文献   

12.
Long VP  Tarrant PV 《Meat science》1990,27(3):181-195
Thirty pairs of Landrace or Large White pigs were used to determine the effects of pre- and post-slaughter cooling treatments on pork quality and yield. One animal from each pair was showered in cold water and after slaughter one side from each carcass was rapidly chilled and the other side was conventionally chilled. Two experiments were carried out in winter: they examined different times of exposure to cooling treatments; a further experiment was carried out in summer time. Showering caused a reduction in the temperature of the deep loin at 40 min post mortem (P < 0·01). Rapid chilling caused a further reduction in carcass temperature and the rate of pH fall was lower (P < 0·05) in the rapidly chilled sides. There was a strong indication that showering in the winter time lowered drip loss in slices of Longissimus dorsi muscle (P = 0·077) whereas showering in the summer time was not effective. Shower water temperature may have been important in this regard. Showering did not lower drip loss in intact pork legs. Rapid chilling was not effective in lowering drip loss in either slices of Longissimus dorsi or intact pork legs. Rapid chilling at -20°C for 3 h without an air blast lowered evaporative chill losses in sides of pork by 27-29% (P < 0·1) compared to normal chilling. Reduced treatments gave reduced effects. Neither treatment had any significant effect on cooking loss or toughness in broiled slices of pork Longissimus dorsi muscle.  相似文献   

13.
Two studies (Study 1 = 23 forage-fed steers; Study 2 = 20 grain-fed steers and heifers) were conducted to determine relationships of electrical stimulation (ES) and/or postmortem aging (PA) to tenderness of beef. For Study 1, steaks from ES sides had lower (P < 0.05) Warner-Bratzler shear (WBS) values than steaks from not-ES sides for each PA period. In addition, the percentage reduction in WBS values was greater for the steaks from the ES-Day 2 group (–29.5%) than for steaks from even the longest PA period (14 days) from the not-ES group (–25.8%). For Study 2, during the fist three PA periods (1, 2 and 5 days), ES resulted in more desirable (P < 0.05) flavor ratings (Day l), higher (P < 0.05) tenderness ratings and lower (P < 0.05) WBS values (Day 1, 2, 5) and more desirable (P < 0.05) overall palatability ratings (Day 1, 2). During the last three PA periods (8, 11 and 14 days), ES resulted in higher (P < 0.05) tenderness ratings (Day 8), lower (P < 0.05) juiciness ratings (Day 11, 14) and lower (P < 0.05) WBS values (Day 8). Based on these results, ES had the greatest impact on beef palatability if the period of aging was 8 days or less; with additional aging time, ES effects on palatability were negated. When each treatment (ES, not-ES) was divided into two groups based on median tenderness ratings for the not-ES group, ES had the greatest impact on those carcasses in the “tough” group while ES had little impact on those carcasses in the “tender” group. ES will accelerate the postmortem aging of beef but the aging time reduction and extent of ultimate tenderization appears to be affected by the inherent tenderness of the beef.  相似文献   

14.
Differences in fat quality, tenderness and composition of raw, roasted and grilled pork loin chops obtained from different meat brands Three loin chops obtained from each of a total of 180 pigs within one slaughter house either were left raw or were roasted at 120 °C for 12 min or simultaneously grilled on both sides at 180 °C for 6 min, respectively. Four different groups of 45 animals each were employed: pigs of conventional origin, pigs from a meat brand basing on animal welfare principles (Neuland) and pigs from two sub-systems of another commercial meat brand (Pigour) among others using higher contents of medium chain fatty acids in the feed. With the less intensive roasting, lower cooking losses and shear forces were observed as compared to grilling. The final intramuscular fat content was almost twice as high as the initial value of 1.3% with both cooking procedures. In subcutaneous back fat, cooking resulted in a highly significant reduction of the proportion of the polyenic acids which, however, was of only low numerical extent. The induction period till fat oxidation was significantly increased by 25% with roasting and by 8% with grilling. The clear differences in the quality of the raw chops obtained from the different origins could be almost completely recovered in the cooked chops.  相似文献   

15.
The low demand for lamb in the U.S.A. requires the sheep industry to focus on the development of a means to simultaneously protect fresh lamb consumption from deteriorating and entice new consumer purchases based on palatability characteristics. Thus, the shelf-life and palatability attributes of lamb enhanced with salt, phosphate and rosemary were compared with traditional, fresh, nonenhanced lamb cuts. Wholesale loins and legs (n  =  30/subprimal) were either injected to 112.5% of raw weight with the enhancement treatment (ENH) or not (Ctrl), and both ENH and Ctrl cuts were vacuum-packaged and stored 24 h before fabrication into 2.54-cm-thick chops/steaks. While color scores decreased (P  <  0.05) for both loin chops and leg steaks over the 7-day display period, sensory panelists preferred (P  <  0.05) ENH lamb over Ctrl chops and steaks. Results indicate that enhancement can improve the palatability attributes of lamb without detrimental effects on product shelf life.

PRACTICAL APPLICATIONS


Information presented in the current experiment can be used as a tool to define the sensory taste and color quality characteristics of solution-enhanced lamb retail cuts. More specifically, this information could be used to support future studies in the areas of color stability/packaging applications and a means to identify a threshold for solution enhancement of lamb muscles. With an industry that relies on the identification of new cuts for the retail market, and consumers placing tremendous emphasis on muscle color at the time of purchase, a thorough understanding of color stability for solution-enhanced lamb is necessary. Lastly, this information can be used to further enhance the potential marketability of such muscles from the lamb carcass that tend to receive severe discounts as a result of a lack in consumer preference for lamb products in the retail setting.  相似文献   

16.
The quality characteristics of biceps femoris (BF) and semimembranosus (SM) roasts obtained from mature cow carcasses treated with a commercial extra low voltage (30 V) electrical stimulation (LVES) system were determined. LVES was applied for either 2 (ESII) or 4 min (ESIII). Evaluations were conducted on meat obtained from control sides (no ES) aged for either 48 h (Ia) or 7 days (Ib) and from ES sides aged 48 h. ES caused a reduction (P<0·001) in pH values at 2 and 6 h post mortem. At 24 h, the pH of muscles from all carcasses was about 5·5. ES duration did not influence muscle pH. Rib-eye muscle colour for ESII and ESIII carcasses was lighter and brighter (P<0·05) than that of control carcasses. Generally stimulated BF roasts had greater cooking losses than control Group Ib roasts; SM roasts from ES carcasses had lower losses than comparable to Group Ib roasts. ES duration had no effect on per cent cooking losses. Trained panelists generally detected few significant effects in BF roasts due to ES. Warner-Bratzler data indicated that ESII and ESIII BF roasts were similar and significantly more tender than comparable control Group Ib samples: OTMS data indicated that all BF roasts were similar in tenderness. However, SM roasts from ES carcasses were judged more soft (Groups II and III) and tender (ESII) than comparable control roasts. Instrumental measurements of tenderness for SM roasts tended to support the taste panel results. Generally, duration of LVES had no effect on the eating quality of either BF or SM roasts. Since LVES effects on the palatability of SM roasts were evident but the effects of stimulation of BF roasts were few, further studies of this LVES system are needed before its use can be recommended. Generally, increasing post-mortem ageing time for mature control carcasses did not influence either BF or SM roast quality.  相似文献   

17.
Pork loin chops with the subcutaneous fat attached, without subcutaneous fat and the subcutaneous fat that was removed from chops were packaged and stored at 4°C±1°C in polyvinyl chloride (PVC) film for 0-6 days or in high-oxygen barrier (HOB) film for 0-28 days. Aerobic plate counts (APCs) of lean and fat of intact chops packaged and stored in either PVC or HOB film did not differ (P>0·05) in most comparisons. The APCs of subcutaneous fat portions that were packaged and stored separately in HOB film often were higher than those of comparable fat samples of intact chops. There was no consistent pattern of differences in the microflora of lean and fat samples. Differences in mean scores for surface discoloration, off odor and overall appearance of intact chops and chops without subcutaneous fat usually were either not significant (P>0·05) or inconsistent. Lean color scores of chops with or without subcutaneous fat did not differ except that chops with the subcutaneous fat removed were rated higher than intact chops during the early periods of storage. Fat color of subcutaneous fat packaged and stored separately in HOB film was often rated higher (slightly whiter) than that of comparable fat of intact chops.  相似文献   

18.
Seventy-two sides (eighteen sides from each sex-breed group) from carcasses of half-blood or three-quarters-to-seven-eighths-blood Charolais bulls or steers of known history and age, handled alike from weaning to slaughter, were used. All cattle were fed in a commercial feedlot (average days-on-feed was 186) and slaughtered in a commercial packing plant. Comparisons were made for percentages of (1) untrimmed wholesale cuts, (2) partially boneless subprimals (trimmed of fat in excess of 1·9 cm), (3) partially boneless retail-ready cuts (trimmed of fat in excess of 0·95 cm) and (4) boneless retail-ready cuts (trimmed of fat in excess of 0·95 cm). Bulls had higher percentages than steers of chuck and round at all stages of trim. Steers had higher percentages of untrimmed, wholesale loin and partially boneless shortloin (1·9 cm fat) than bulls but steer percentages of shortloin cuts trimmed to 0·95 cm of fat did not differ from those of bulls. Bulls averaged 48·05%, while steers averaged 45·45%, major boneless, closely trimmed retail-ready cuts. After the lean trim was adjusted to 25% chemical fat, bulls had 27·70% lean trim and 5·65% fat trim while steers had 24·30% lean trim and 12·15% fat trim. No difference in the percentage of retail-ready cuts was attributable to breed; however, the three-quarters-to-seven-eighths-blood Charolais group had a lower percentage of standardized fat trim and a slightly higher percentage of bone than the half-blood group.  相似文献   

19.
Duroc, Meishan, Fengjing and Minzhu boars were mated to White composite gilts. Trained sensory panel evaluation and Warner-Bratzler shear force determinations were made on chops that had been aged 4 days postmortem. No differences (P > 0.05) were found in juiciness, connective tissue amount, flavor intensity, tenderness or shear force values among sire breeds. No differences (P > 0.05) were detected in cooking losses, although meat from the Duroc-sired pigs cooked at a faster (P < 0.05) rate, but required longer cooking (P < 0.05) times than that from the other sire breeds. These data indicate the introduction of currently available Chinese genetics into the U.S. swine population would have little effect on the palatability of pork loin chops.  相似文献   

20.
Retail pork from eight US cities was obtained for quality and palatability evaluations. Boneless pork loin chops were classified into one of three quality categories - "high," "average," or "low" - with higher quality chops possessing more desirable color, marbling, juiciness, and shear force characteristics than lower quality chops. Loin chops that were enhanced (injected with solution to improve juiciness and/or tenderness) had higher (P<0.05) pH, less purge and cook loss, and higher palatability ratings compared to non-enhanced chops. Hams compared by their protein fat free (PFF) classifications showed that ham and water product received the highest (P<0.05) ratings for juiciness and tenderness, and ham with natural juices received the highest (P<0.05) texture, ham flavor intensity, and smoke flavor ratings. Bacon was compared by price/brand categories; however, the highest priced, national branded bacon (US$12.03/kg) was similar (P>0.05) for most quality and all palatability traits to the lowest priced, national branded bacon (US$6.47/kg) and the store branded bacon (US$8.30/kg) even though retail prices differed widely. Overall, there were tremendous ranges in values for these products indicating that retail pork is quite variable and that efforts to improve the quality and consistency of it must continue.  相似文献   

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