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1.
Sanitary conditions were monitored at eleven supermarkets (from two major chains, Sup groups A & B) in the South African butcher industry. The variables measured were the temperature of carcasses and environments, the muscle pH of carcasses and the microbiological status of carcasses and human or personal and equipment contact surfaces (chillers-three surfaces, delivery trucks-five surfaces, cutting rooms-16 surfaces). All supermarkets, except one, received beef carcasses, distributed by one of two wholesale organizations from the same abattoir. No consistency was found in the contamination level of different parts of carcasses at different supermarkets, although there was a tendency for fore quarters to be more contaminated than hind quarters. Chiller surfaces, delivery truck surfaces and equipment had significantly different microbial counts at the different supermarkets. Sup group B received carcasses with higher mean surface temperatures and microbial counts than those of the carcasses received by Sup group A, but the mean microbial count of equipment was lower than that encountered at Sup group A. The result was less contaminated meat at the supermarkets in Sup group B, illustrating how a combination of the microbial quality of carcasses received by such supermarkets, and the sanitary programme in operation at such supermarkets affects the contamination level of retail premises. It could furthermore be shown that personnel surfaces (hands and clothes) and equipment like saws and mincers are consistent contributors to contamination at the retail level of the meat industry.  相似文献   

2.
World rabbit meat production is estimated to be over 1 million tons, and Spain is the third largest producer. Although rabbit meat is marketed and consumed worldwide, information on microbiological quality is very scarce. Here, we report indicator organisms, spoilage flora, sensory quality, and some physicochemical traits of 24 h postmortem chilled rabbit carcasses and prepackaged rabbit meat stored chilled in air for 0 to 3 days at the retail level. The mean total bacterial count (4.01 +/- 0.48 log CFU/g) for carcasses dressed at a small abattoir by a manual process was significantly lower (P < 0.05) than that (4.96 +/- 0.90 log CFU/g) for carcasses dressed at a large abattoir in automated slaughter lines. Both groups of carcasses had mean pH values of 5.98. The dominant contaminants on carcasses from the small abattoir were Pseudomonas, lactic acid bacteria, and yeasts. These microorganisms and Brochothrix thermosphacta were dominant on carcasses from the large abattoir. On prepacked hind legs (pH 6.26 +/- 0.18) stored at -1 to +1 degree C (supermarket 1), mean aerobic mesophilic count was 5.87 +/- 1.03 log CFU/g, and the major microbial groups were Pseudomonas, yeasts, lactic acid bacteria, and B. thermosphacta. On prepacked whole carcasses (pH 6.37 +/- 0.18) displayed at -1 to +5 degrees C (supermarket 2), mean aerobic mesophilic count was 6.60 +/- 1.18 and the same microbial groups were dominant. Relative Escherichia coli incidence was supermarket 2 > large abattoir > supermarket 1 > small abattoir. Overall, low numbers of coliforms, Enterobacteriaceae, psychrotrophic clostridia, coagulase-positive staphylococci, and molds were found. Sensory scores, pH values, and L-lactic acid content differentiated fresh carcasses from retail samples. Data obtained suggest that the microflora of chilled rabbit meat are different from those found on the meat of other animals.  相似文献   

3.
The influence of effective low voltage electrical stimulation on the colour stability of beef topside (semimembranosus) muscles, during storage and retail display was studied using objective measurements and subjective assessments. Earlier results obtained from objective measurements demonstrated that during a three day retail display period, stimulated topsides had a greater loss of colour than non-stimulated topsides, and primal cuts aged for 33 days at 0 °C before display suffered faster changes to colour during retail presentation than cuts aged for 5 days. To relate results obtained using objective methods to consumer perceptions of meat quality, consumer perceptions of samples of meat displayed for 3 days in the retail cabinets of a major local supermarket were recorded. A total of 960 consumers were asked to evaluate topside steaks for meat and fat colour, meat discolouration and acceptability. During 3 days of retail display, consumers did not perceive differences in the extent of discolouration of topside steaks from electrically stimulated and non-stimulated carcasses; for the majority of the treatment groups (high or low pH muscles, 5 or 33 day ageing, 1-3 day retail display) there were no significant differences, for any of the scored attributes, between stimulated and non-stimulated samples. However, for samples in the fresh (5 days ageing), high pH (5.8-6.0) treatments group, lean meat colour and acceptability for the stimulated samples were, on some of the days on display, given significantly (P < 0.05) better ratings by the consumers than those from corresponding non-stimulated samples.  相似文献   

4.
The aim of this study was to analyze the influence of the chilling method on meat quality and the microbiological durability of pork cuts during storage. The left half‐carcasses were put through the shock tunnel and the right half‐carcasses were placed directly in the chilling room. After chilling, pH measurements were taken in two muscles. The carcasses were cut, and drip loss, marbling, and color of LL muscle were estimated. The microbiological quality of meat elements was estimated according to the procedure included in the EC regulation. The total viable count tests were done after chilling, 8, 12, 14, 16, and 18 days of storing. The drip loss was higher in the group that was chilled slower. In the group of carcasses chilled quickly lower mass losses were observed. The positive effect of ?26 °C in the shocking tunnel on the microbial quality of carcass and vacuum packed primal cuts was not as intensive as expected. As showed the above presented results of the study, the economic aspect of pork carcass chilling system first of all should be taken under consideration in meat production.

Practical applications

The study shown that very low temperatures in the shock tunnel in chilling process of the pig carcasses (e.g., ?26 °C) do not bring the expected results as a significant increase in the shelf life of meat cuts and quality of meat. Therefore, it is useful to modify the regime of temperature through the use in industrial practice of higher temperatures in the shock tunnel. The economic aspect of pork carcass chilling system first of all should be taken under consideration in choosing of the chilling method.  相似文献   

5.
Even though worldwide production of rabbit meat is over 1,000,000ton, little information is available on rabbit meat microbiology. This paper reports on the microflora developing on chill-stored rabbit carcasses. Four different lots of 24h post-mortem rabbit carcasses dressed and kept at 0°C in a medium-size abattoir were collected and evaluated for sensory, physicochemical and microbiological changes during aerobic storage at 3±1°C. Mean initial pH value (pH(24)), extract-release volume (ERV) and lactate content of Biceps femoris muscle, were 6.26±0.20, 13.50±3.50ml and 0.70±0.07%, respectively. As with other muscle foods kept chilled in air, pH increased and ERV and lactate decreased as storage progressed. Initial levels (logcfu/g) of aerobes (APC), psychrotrophic flora, Pseudomonas spp., Brochothrix thermosphacta, lactic acid bacteria, Enterobacteriaceae and yeasts were 4.76±0.31, 4.81±0.81, 3.39±1.12, 2.01±0.92, 2.76±0.51, 0.49±0.45 and 3.46±0.32, respectively. Pseudomonads, most of them fluorescent, and to a lesser extent B. thermosphacta and yeasts grew faster than the remaining microorganisms and became predominant at the end of the shelf life. Carcasses spoiled when mean APC, psychrotrophic and pseudomonads numbers were ca. 8logcfu/g, their mean shelf life being estimated at 6.8 days. A lot of DFD-like rabbit carcasses, with higher pH and lower ERV values but similar microbial loads to normal meat, developed a strong putrid odour after 4 days.  相似文献   

6.
Centralized packaging of retail meat cuts is growing more popular because of its economies and potential to maintain quality, enhance safety, and extend the shelf life of fresh meat. Requirements for optimizing shelf life of centrally prepared retail cuts for periods up to 15 weeks are slightly different from those needed to extend the shelf life of fresh, chilled meat. Chilled meat primarily deteriorate at the cut or uncut muscle surface. In long-term storage, primal cuts are placed in an atmosphere saturated with carbon dioxide and containing very low residual oxygen. These cuts are held at -1.5+/-0.5 degrees C. When the meat is removed, it is fabricated into retail or food service cuts. New fresh surfaces are created in the process, revitalizing the meat's appearance. After being prepared for retail display, the meat normally has four more days of shelf life. Depending on the meat species, shelf life is usually limited by development of undesirable organoleptic changes, usually defects in color, which are independent of microbial presence. The microbes consist of a lactic acid bacterial population that maximizes under storage conditions at about 10(8) CFU/cm2 well before shelf life ends. Circumstances are different with centralized distribution of retail-ready fresh meat. The wholesale storage period following initial packaging of the retail cuts is about 20 to 30 days. Prepared products must withstand retail display for up to 2 days without further manipulation of package contents. Retail packages are simply moved from their storage container (usually a unit or overwrap containing a modified atmosphere) to retail display, where desirable meat color develops upon exposure to air. Three gas atmospheres have some potential to satisfy storage needs for centralized distribution of retail-ready packages: 100% CO2, 100% N2, or 70% N2 + 30% CO2. Shelf life is limited by undesirable changes in surfaces exposed at initial packaging, caused by growth of psychrotrophic bacteria. If 100% CO2 is used, these are all lactic acid bacteria (LAB). Therefore, initial bacterial numbers on the meat and storage temperature become critical to success. The most attractive storage option is 100% CO2 used at - 1.5 +/-0.5 degrees C. This review presents the reason for that recommendation, along with basic concepts of meat chemistry, a discussion of modified atmosphere packaging, meat microbiology, and current results with simulated centralized packaging of retail-ready meats.  相似文献   

7.

ABSTRACT

In order to achieve an adequate level of tenderness while reducing chilling and technological losses, the effect of two aging methods (on the carcass or under vacuum packaging) on the shelf life (5‐day retail display) of meat from eight Podolian young bulls (16–18 months old) was assessed. Most of the recorded variables were not affected by the interaction aging method × time of display (P > 0.05). These results indicate that the shelf life of meat from Podolian cattle was not influenced by the aging method. In both aging methods, redness a* increased after 1 day of display and subsequently decreased (P < 0.001). Lipid oxidation and total aerobic mesophilic count increased significantly during retail display (P < 0.001). We concluded that vacuum packaging may be conveniently used for the maturation of primal cuts from Podolian carcasses to save energy and space, and prevent chilling and technological losses.

PRACTICAL APPLICATIONS

The aging under vacuum of individual bovine primal cuts can save energy and space as well as prevent chilling and technological losses generally occurring when meat is aged on carcass. This method had no negative effects on meat shelf life. Thus, it may be conveniently used to apply sufficiently extended maturation periods to the meat, which are needed to increase tenderness to a level, which is not prejudicial to product acceptability.
  相似文献   

8.
Gill CO  Landers C 《Meat science》2005,69(3):501-507
To obtain information about the microbiological quality of horse meat exported from North America, the microbiological conditions of hot or cold boned primal cuts and carcass quarters from horse carcasses processed at a North American packing plant were examined. In addition, temperature histories were obtained from boxes of hot boned meat during cooling, and from horse carcass quarters air freighted to Europe. The log mean numbers of aerobes recovered from horse carcasses after dressing were >2 logcfu/cm(2). Log total numbers of coliforms and Escherichia coli recovered from 25 samples from such carcasses were >2 log and <2 logcfu/2500 cm(2), respectively. Numbers of bacteria generally similar to those were recovered from cooled carcasses or hot or cold boned cuts. The cooling process for hot boned meat met with standards for hot boned beef cooling processes based on calculated growth of E. coli at box centres. The deep tissues of carcass quarters cooled and the temperatures of their surfaces rose during air freighting, but surface temperatures mostly remained below 7 °C. The microbiological condition of horse carcass quarters delivered to plants in Europe would likely be comparable with the microbiological conditions of hanging beef delivered from packing plants to distant customers within North America.  相似文献   

9.
Scientific investigation on the quality changes of processed meat products will boost and sustain the meat production and utilization in buffalo abundant countries. A programme was undertaken to compare the quality of buffalo meat patties made from intensively reared young male, semi extensively reared spent male and female groups and stored at refrigeration temperature (4 ± 1 °C). Buffalo meat patties were evaluated for shelf life attributes by analysing the changes in physicochemical, microbiological and sensory attributes. The overall acceptability of patties was better in spent buffalo group than young male group. Increasing storage time resulted in significantly higher pH, TBARS, total aerobic mesophils, coliforms, Staphylococcus aureus and psychrophilic counts but decreased appearance, flavour, juiciness, tenderness, connective tissue residue and overall acceptability scores of buffalo meat patties. The patties were well acceptable within 20 days in young male group and 25 days in spent buffalo group respectively during refrigerator storage.  相似文献   

10.
There is a gap in knowledge of microbiological quality in raw chicken products produced by nonconventional methods and no studies have reported the microbiological quality of turkeys produced under different rearing environments. Thus, the aim of this study was to compare the microbiological quality of conventionally and organically reared whole chicken and turkey carcasses purchased from 3 retail outlets in Knoxville, Tenn., U.S.A. A total of 100 raw broiler chickens organically (n = 50) and 50 raw turkey carcasses consisting of 3 brands reared either conventionally (n = 25) or organically (n = 25) were evaluated. The FDA BAM protocol for rinsing poultry carcasses was used to enumerate of aerobic bacteria, Campylobacter, and Staphylococcus spp., and for qualitative analysis of Salmonella. Organic chickens from one brand had the highest average counts of aerobic bacteria, Staphylococcus spp. and Campylobacter (4.8, 4.8, and 4.7 Log10 CFU/mL rinsate, respectively) while the other organic brand had the lowest average counts (3.4, 3.3, and 3.1, respectively) of all 4 brands evaluated. The organic turkeys had the highest average counts of these same bacteria (4, 3.9, and 3.8, respectively) compared to the 2 brands of conventional turkeys evaluated. Salmonella (5% prevalence) was isolated only from organic chickens and turkeys. From these data, it appears that the microbiological quality of the raw product was not dependent on rearing conditions and, thus, it cannot be assumed that organic raw poultry is safer than conventionally raised poultry in terms of microbiological quality.  相似文献   

11.
Argentina has the highest incidence of HUS in the world. HUS is produced by STEC O157 and non-O157. Cattle's faeces and hides are sources of STEC contamination of carcasses during slaughter. We investigated the presence of STEC in carcasses and cuts of meat in the marketing chain in an agricultural city located in Buenos Aires Province (Argentina). In this study, the detection of the stx gene was used as an indicator of carriage of meat with STEC. In carcasses, we detected 12.34% and 18.64% of STEC at the slaughter and sanitary control cabin (place where carcasses arrive from slaughters located outside the city), respectively. These percentages increased at butcheries (24.52%). The 25% of retail beef cuts were STEC-positive with significant differences among the different cuts of meat (chuck: 12.12%, rump roast: 12.12% and minced beef: 40.74%). The stx2 gene was the predominant gene detected in all samples at different levels of the commercialization meat chain.  相似文献   

12.
The study was envisaged to develop and extend the shelf life of the highly perishable Indian traditional meat product, chevon (capine) keema, through the application of hurdle technology.The hurdles used were water activity (a(w)) and pH as variable hurdles as well as vacuum packaging, preservatives and heat treatment as constant hurdles. The water activity of the product was adjusted to 2 levels viz., 0.90 and 0.88 by the addition of humectants. The product with 0.90 was preferred for sensory quality. The pH of the keema was adjusted with lactic acid to 3 desired levels viz. 5.50, 5.65 and 5.80. The product with pH 5.8 was the most acceptable and with pH 5.50 was the least acceptable. Standardised keema with a(w) 0.90 and pH 5.80 was stored at ambient temperature (36.2±1.2°C) and evaluated for physico-chemical, microbiological and sensory characteristics. A gradual increase in moisture, a(w), thiobarbituric acid reactive substances (TBARS) number and tyrosine value were observed throughout the storage period. There was a decrease in the growth rate of aerobic and anaerobic counts and complete inhibition of Staphylococcus aureus. Although sensory scores for hurdle treated keema declined upon storage, the product was well accepted up to the 3rd day and fairly accepted up to 5th day whereas the keema prepared by the traditional method was acceptable only on the first day. Hurdle technology significantly improved the shelf life of keema.  相似文献   

13.
To establish the shelf-life of vacuum packaged Australian beef, 15 Strip-loins and 15 Cube-rolls for each Processor (A, B, and C) were evaluated at two week intervals (since wk 10 to 20). Steaks on the trays were placed in retail cabinets at 3 °C. Shelf-life evaluation was based on off-odor (only at week 10), microbial analysis, lipid oxidation, and color assessment by trained panelist and Hunter colorimeter. Panelists detected "slightly off-odor" in both primal cuts for Processors B and C (P<0.05). Processor A primal cut steaks displayed better color scores as well as CIE L*, a*, b*, Chroma and Hue values during storage and display period than steaks from the other processors. Also, primal cuts from Processor A showed lower microbial counts and TBARS values with respect to other processors during the trial. Processor A cuts showed improved shelf life attributes initially which helps to explain its slow shelf-life deterioration.  相似文献   

14.
The bacteriological status of 286 primal cuts stored frozen in intervention stores in England, Scotland and Northern Ireland for between 18 and 216 weeks was assessed in two surveys carried out during 1993 (120 cuts) and 1994 (166 cuts). Overall the aerobic plate count at 25°C and the presumptive pseudomonad counts were <105 cm2 on 269 (94%) and 273 (95·5%) of the cuts, respectively. Similarly the coliform and enterococcal counts were <103 cm2 on 98·3% and 97·9% of the cuts, respectively. These findings suggest that the quality of dressing and butchery of the carcasses was of a generally satisfactory standard although on occasions there may have been suboptimum hygiene control during slaughter and butchery or some delay before freezing. The bacterial numbers were higher on average on the cuts obtained from the lower part of the carcass while there was a tendency for the number of aerobic spoilage organism to decrease slightly with increasing storage time. Evidence was obtained in the second survey which indicated differences between microbiological quality of meat coming from different boning plants although it was not possible to make a detailed evaluation of this point as the number of cuts available for sampling from each plant differed in each year.  相似文献   

15.
This study was undertaken to determine the microbiological quality of sheep carcasses during different stages in the slaughtering process. A total of eleven carcasses were selected at random in an abattoir. The samples were taken by excision from four different sites; leg, brisket, shoulder and neck. The samples were collected from the same carcasses at four different stages in the slaughtering process; after dressing, after evisceration, after washing and chilling. The aerobic mesophilic bacteria, coliforms and Enterobacteriaceae recovered from each sample were enumerated. Chilling reduced the aerobic mesophilic and coliform counts of carcasses, significantly. Levels of carcass microbial load after chilling were 1.69, 0.11 and 0.11 log cfu/cm2 for aerobic mesophilic counts, coliform counts and Enterobacteriaceae counts, respectively. According to data obtained in the present study, chilling of carcasses was the most important step in improving the hygienic quality of carcasses. Processing stages changed significantly both aerobic mesophilic and coliform counts of neck, therefore, among different sites of carcass, neck should be the only critical site for microbiological sampling for sheep carcasses.  相似文献   

16.
We investigated pasteurization and storage of blue crabmeat in steel cans, aluminum cans, plastic cans, nonbarrier pouches, and barrier pouches. Fresh meat was packed in copolymer polyethylene/polypro-pylene cups, Saran® over-wrapped or vacuum skin packaged polystyrene trays, and nonbarrier pouches. Meat pasteurized in plastic and aluminum cans had better sensory and microbiological quality and longer shelf life than meat packed in steel cans. Oxygen-barrier pouches had the lowest quality and shortest shelf life. Nonbarrier pouches had product with quality similar to meat in steel cans, but with an extended shelf life. No packaging materials improved the microbiological shelf life of freshly cooked meat. Vacuum skin packaging resulted in improved sensory qualities of freshly cooked and picked meat.  相似文献   

17.
The effect of storage temperature on microbial and sensory quality of retail cuts of pork was determined on samples stored under temperature regimens designed to simulate conditions that could be encountered in accessing distant markets with retail-ready product. Samples were packaged in modified atmosphere with 100% CO(2) and <200 ppm O(2) in plastic film with extremely low gas transmission rates. All samples were stored at -1·5°C for three weeks. Reference samples were held at -1·5°C for the duration of the study; experimental samples were transferred to 4°C (-1·5 4° C ) or 7°C (-1· 517° C ) and analyzed for microbial content and sebsory attributes including appearance, confinement and meat odours. Storage life of reference samples at -1·5°C was seven weeks before rejection for loss of acceptable appearance. With transfer of samples to 4 and 7°C after three weeks at -1·5°C, samples remained acceptable for retail sale for two weeks and one week, restpectively. The microbial flora was dominated by lactic acid bacteria under all three storage conditions. Appearance of the cuts was the principal criterion limiting storage life. Discoloration of the meat was not a problem in this study, but purge and odour, including sour and sulphur notes, became a problem with time. The study indicated that export of retail-ready pork cuts to distant markets with a three-week time for delivery to market at -1·5°C can be achieved with one to two weeks of marketing time at retail market at 4 to 7°C.  相似文献   

18.
The effect of an advanced vacuum skin packaging system on the microbiological and physicochemical properties of fresh retail cuts of beef (including meat portions from six different anatomical regions) stored at 4 degrees C was compared with the effect of traditional vacuum packaging. The vacuum skin packaging system whose effect on meat quality was evaluated in this work displayed two remarkable features: (i) the instantaneous heating of the lower surface of the upper film of the package before the film descended over the meat surface and (ii) the tight disposition of the plastic film on the meat surface, which avoided wrinkles and purges. Throughout storage at 4 degrees C, rates of bacterial growth were statistically significantly slower in beef portions processed with the vacuum skin packaging system than in those processed with traditional vacuum packaging, with average differences of 2.07, 1.60, and 1.25 log CFU/g in counts of aerobic mesophiles, anaerobes, and lactic acid bacteria, respectively. pH values were statistically significantly lower for beef portions packaged with the vacuum skin system than for those that were vacuum packaged in the traditional manner, probably because of the relative predominance of lactic acid bacteria observed in such samples, which coincided with both higher meat firmness values and a slower meat tenderization process. The vacuum skin system prevented the appearance of undesirable coloration on the meat surface and also significantly improved the commercial color of the meat as determined on the basis of luminosity (L*) and the redness (a*). Overall, the quality (as determined by microbiological and physicochemical analyses and by visual examination) of fresh retail cuts of beef packaged with the vacuum skin system and stored at 4 degrees C was higher than that of meat samples processed with the traditional vacuum-packaging system.  相似文献   

19.
A total of 216 pork loin subsections were utilized to investigate the effects of storage atmosphere (100% N(2); 100% CO(2); or 70% O(2) and 30% CO(2)), storage temperature (-1.5, 2 or 5 °C) and duration of chilled storage (≤28 days) and subsequent aerobic display (≤30 hr) on the retail properties and storage life of display-ready pork cuts. Composite results clearly emphasize the importance of subzero storage to the retail properties, and storage life of pork for all the types of storage atmosphere utilized. However, in the present study, controlled atmospheres of 70% O(2) and 30% CO(2) possessed the greatest preservative properties for masterpacked display-ready pork loin subsections (roasts) during chilled storage for up to 24 days, based upon visual and olfactory criteria. A decrease in retail appearance, attributable to a progressive increase in surface discoloration during both chilled storage and subsequent, aerobic display, resulted in a increase in the incidence of unacceptable packages, during both chilled storage and subsequent, aerobic display, which restricted chilled storage life to 20 days or less. Storage time consistently exerted the greatest influence on retail properties and generally accounted for 80% or more of the variation in most attributes evaluated. In addition, off-odors developed progressively during both chilled storage and subsequent, aerobic display, which further restricted chilled storage life to 12 days. Consequently, based upon previous cited results, for distribution of display-ready pork cuts to be successful, the hygienic quality of the commercial product must be improved.  相似文献   

20.
ABSTRACT: Contamination levels (cfu/g and cfu/cm2) of indicator microorganisms in retail broiler chicken carcasses in León (Spain) were investigated. Counts (log10 cfu/g) were 5.19, 3.04, 2.73, 3.38, and 3.16 for total aerobic counts ( TAC), Enterobacteriaceae , coliforms determined by the standard VRBA method (coliforms-VRBA), coliforms determined by the Hydrophobic Grid Membrane Filter method (coliforms-HGMF), and Escherichia coli (HGMF method), respectively. These values fit into the microbiological criteria for poultry meat consulted. A low correlation coefficient was found between TAC and Enterobacteriaceae counts (r = 0.308; P = 0.053) and between coliforms-VRBA and coliforms-HGMF counts ( r = 0.398; P = 0.048). The determination method had a significant influence on the coliform counts obtained. All broiler chicken carcasses harbored E. coli biotype I. E. coli biotype II was detected in 20% of the samples. The HGMF method was not completely specific for detecting E. coli since 11.25% of false positive colonies were found.  相似文献   

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