Level Of Microbiological Contamination Research Articles

Contamination of bivalve molluscs by Cryptosporidiumoocysts: the need for new quality control standards

A yearlong study was carried out to investigate the presence and viability of Cryptosporidium oocysts in 203 samples of cultured shellfish from Galicia (NW Spain) and 38 samples imported from other European Union (EU) countries. Shellfish samples included mussels, oysters, clams and cockles. Cryptosporidiumoocysts were detected, using a direct immunofluorescence antibody test (IFAT), in 34.4% of the samples analyzed; use of the fluorogenic dye propidium iodide (PI) revealed viable potentially infective oocysts in 53.0% of these samples. There was no relation between the presence of Cryptosporidium oocysts and the microbiological contamination detected in the samples expressed as Most-Probable-Number (MPN) of fecal coliforms, the different species of mollusc, or the month of sampling. One important finding was that the depuration process was ineffective in totally removing oocyst contamination. Furthermore, the existence of viable oocysts in samples with microbiological contamination levels lower than 300 fecal coliforms/100 g, which in accordance with current legislation are considered suitable for human consumption, suggests the need to include parasitological analyses in the quality control for these molluscs.

Combined Effects of Lactic Acid and Nisin Solution in Reducing Levels of Microbiological Contamination in Red Meat Carcasses

Changes in bacterial counts on beef carcasses at specific points during slaughter and fabrication were determined, and the effectiveness of nisin, lactic acid, and a combination of the lactic acid and nisin in reducing levels of microbiological contamination was assessed. Swab samples were obtained from the surfaces of randomly selected beef carcasses. Carcasses were swabbed from the neck, brisket, and renal site after skinning, splitting, and washing. Treatments involving lactic acid (1.5%), nisin (500 IU/ml), or a mixture of nisin and lactic acid were applied after the neck area was washed. A control group was not sprayed. Results indicated that the highest prevalence of aerobic plate counts (APCs), total coliforms, and Escherichia coli was found in the neck site after splitting, and the lowest level of microbial contamination was found after skinning. Washing with water did not significantly reduce the bacterial load. The largest reduction in APCs, total coliforms, and E. coli occurred on carcasses treated with a mixture of nisin and lactic acid. A mixture of nisin and lactic acid can be applied to beef carcasses through spray washing and can reduce bacterial populations by 2 log units.

Conservação refrigerada de carambolas em embalagens plásticas

Pesquisou-se o efeito de duas embalagens (polietileno de baixa densidade - PEBD e polipropileno - Longa Vida Pak ou LVP) em relação ao controle (sem embalagem) sobre a conservação de carambolas em atmosfera refrigerada (10 ºC). Utilizou-se o planejamento fatorial inteiramente casualizado 3 x 4 x 2 (3 embalagens x 4 períodos de armazenamento x 2 repetições). As análises para acompanhamento do armazenamento foram: pH, ºBrix (sólidos solúveis), acidez titulável, perda de peso, coliformes totais e fecais, bolores e leveduras. O nível de contaminação microbiológica (bolores e leveduras) foi aceitável até 21 e 28 dias para carambolas não embaladas e embaladas, respectivamente. A embalagem LVP apresentou os menores índices de contaminação. Em relação às alterações físico-químicas, não houve diferenças significativas entre as embalagens com relação a perda de peso, pH e acidez titulável e o teor de sólidos solúveis foi maior para os frutos armazenados em embalagens LVP. Os resultados globais indicam que ambas as embalagens aumentam a vida útil deste produto e que, do ponto de vista microbiológico, a embalagem LVP foi melhor que a embalagem PEBD para a preservação sob condições refrigeradas.

Pathogenic micro-organisms in slaughterhouse sludge--a survey.

During slaughtering of animals and subsequent meat processing the process water used becomes polluted with organic matter of animal origin (i.e. protein and fat). This organic sludge is, in principle, a product suitable for animal feeding. To investigate the microbiological contamination level of sludge, raw sludge was collected at pig (n = 8) and poultry (n = 5) slaughterhouses. Both flocculated and aerobically activated sludge was monitored. Slaughterhouse sludge was heavily contaminated with Enterobacteriaceae (6.3-10.0 in log10 N/gram dry matter) and enterococci (4.6-7.9). Clostridia were present in sludge at a level of 3.1-5.8 (in log10 N/g DM). Salmonella was present in the sludge from all slaughterhouses examined. Yersinia enterocolitica serotypes O:3 and O:9 were found in sludge from seven out of thirteen slaughterhouses. The prevalence of Campylobacter jejuni/coli was higher in flocculated poultry sludge than in both flocculated pig sludge and aerobically activated pig sludge. Obviously, decontamination of the sludge is mandatory when it is to be applied as a feed constituent, to prevent bacterial cycles from occurring in livestock, as well as the spread of human pathogenic zoonoses like campylobacter, salmonella and yersinia, to minimize loss of protein quality by the microbial breakdown of amino acids and the formation of possible toxic metabolites in sludge during storage.

Microbiological Contamination of Carcasses Related to Hygiene Practice and Facilities on Slaughtering Lines

The purpose of the study was to investigate the association between the hygienic practice of slaughterhouse workers and the microbiological contamination level of carcasses. In 5 Finnish slaughterhouses the workers' hygienic practice was observed and the carcasses were sampled by the swabbing method. The overall means (log10 cfu cm-2) of the aerobic plate count in pork and beef carcasses were 3.23 and 2.65, respectively. Hygienic practice was found to be associated with the carcass contamination level, especially the disinfection frequency. In those slaughterhouses, where the disinfection frequency was low, the contamination level of carcasses was high. Designing slaughtering lines so as to make hygienic working possible is evidently very important. However, the enforcement of hygienic practice, such as the regular disinfection of working tools, is also important in reducing the microbiological contamination of carcasses.

The effect of different on-line dressing practices on microbiological and visible contamination of lamb carcasses

Three dressing practices were assessed in traditional lamb carcass dressing systems for their ability to improve control of microbiological and visible contamination. The routine removal of a piece of skin from the perineal area reduced total aerobic plate counts and Escherichia coli counts on carcasses derived from both woolly and shorn groups of lambs. Similar results were found when the "Y-cut" was delayed in the dressing sequence, but E. coli counts increased slightly in one group. The use of a wide-blow shear prior to the opening cut on the hindleg of carcasses derived from woolly lambs resulted in a slight increase in the microbiological contamination on the leg. The removal of a piece of skin from the perineal area reduced scores for faecal contamination despite a small increase in contamination with wool. Changes in visible contamination in response to the two other dressing procedures were principally effected through changes in levels of contamination with wool. Irrespective of dressing procedures, levels of microbiological and visible contamination were lower on carcasses derived from shorn compared with woolly lambs. These studies demonstrated that, although they are reasonable indicators, the use of parameters of visible contamination as a measure of carcass hygiene must be treated with caution. This is especially the case if a genuine HACCP-based system for the control of dressing hygiene for a particular class of slaughtered livestock is to be implemented.

Microbiological and Visible Contamination of Lamb Carcasses According to Preslaughter Presentation Status: Implications for HACCP

The effective design and implementation of hazard analysis and critical control point (HACCP) systems for fresh meat is dependent on identification of those process steps that determine most of the contamination on the carcass, and institution of appropriate critical limits. Eight groups of 25 lamb carcasses of different preslaughter presentation statuses were subjected to excision sampling at multiple sites for microbiological contamination, and detailed examination for visible contamination. Examinations were conducted in a traditional dressing system after pelting, after pre-evisceration washing, at chiller loading, and at the end of the chill cycle.Mean levels of microbiological contamination on carcasses immediately after pelting (log10 aerobic plate count/cm2) (APC) ranged from 4.63 on those derived from dirty woolly washed lambs to 3.93 on those derived from clean shorn unwashed lambs. Higher APCs were found on carcasses derived from groups of lambs with a long wool and/or dirty, and washed preslaughter status. There was a significant interaction between long wool and preslaughter washing at pelting, and differences between groups were “smoothed” as APCs generally trended downwards throughout subsequent process steps. Only long wool and preslaughter washing remained as significant factors associated with higher levels of contamination at the end of the chill cycle. Levels of visible contamination in different categories had a variable pattern, and carcasses derived from unwashed lambs had markedly higher rates of “other” and faecal contamination, a trend contrary to that for microbiological contamination. The pre-evisceration wash removed almost all contamination with wool, but had little effect on visible fecal contamination.The results of this study suggest that attempts to use visible contamination as a parameter to monitor microbiological hygiene on carcasses at a designated critical control point in a HACCP system for red meat must be undertaken with caution. It would appear more appropriate to effect HACCP-based process control by monitoring the preslaughter presentation status of the animals, along with correct operating procedures at pelting and appropriate communication loops, rather than using on-line monitoring of the product itself for visible carcass contamination.

Computerised data collection systems have not improved data collection

<h3>Background</h3> Chemical disinfectants have traditionally been used to clean pharmaceutical facilities to ensure acceptable microbiological conditions. However, the use of such agents are costly, time-consuming and environmentally undesirable. Exchanging the disinfectants with sterile water and composite fibre cloths was tested in a class A hospital pharmacy compounding environment with regard to their effects on microbiological contamination. <h3>Purpose</h3> The goal of the project was to establish whether an acceptable level of microbiological cleanliness could be upheld in the production facility when cleaning with sterile water and composite fibre cloths instead of traditional chemical disinfectants. <h3>Material and methods</h3> The sterile chemical disinfectants used were an alternating regimen of Klercide Quat/Biguanide, Amine, Sporicidal low residue peroxide and neutral detergent, provided by Ecolab (St Paul, MN, USA). The alternative system, consisting of sterile water and composite fibre cloths, was provided by De forenede dampvaskerier (Viima, Maribo, Denmark). Klercide Sterile 70% ethanol (Ecolab, St Paul, MN, USA) was used for disinfection of grade A between each production, and for surface disinfection of materials to be transferred into grade A. The effect of cleaning methods was compared for four pharmaceutical isolators and two biological safety cabinets, all of class A grade. The quality of the microbiological conditions was monitored with glove prints, settle plates and contact plates (Tryptone Soya Agar, Oslo University Hospital, Oslo, Norway). The rate of contaminated tests (≥1 cfu/plate) for glove prints, settle plates and contact plates in class A in a 24 month period before and after the change in cleaning method were compared. <h3>Results</h3> The rate of contaminated tests were comparable for the 24 month period before and after the change in cleaning method. The rate of positive tests (≥1 cfu/plate) were for glove prints 5.3% before (n=1562) and 5.0% after (n=1584), settle plates 3.2% before (n=809) and 3.0% after (n=824) and contact plates 2.7% before (n=807) and 1,5% after (n=817). <h3>Conclusion</h3> The level of microbiological contamination in a class A hospital pharmacy compounding environment is maintained when cleaning with sterile water and composite fibre cloths, compared to traditional cleaning with chemical disinfectants. <h3>References and/or acknowledgements</h3> None. No conflict of interest.

EFFECT OF MODIFIED ATMOSPHERE PACKAGING ON COLOR STABILITY AND ON MICROBIOLOGY OF TURKEY BREAST MEAT

ABSTRACTThe effects of several modified atmospheres (100% O2, 100% N2, 100% CO2+ O2scavenger, and 25% CO29% N266% O2) and vacuum on the color stability of turkey were studied. Microbiological examinations were performed at days 0, 7, 14 and 21. pH and pigment content measurements were performed at days l and 2, respectively. Color coordinates were determined at intervals of 2, 5, 7, 11, 14 and 21 days storage in the CIELAB system (1976). Meat kept under vacuum and 100% CO2+ O2scavenger treatment showed the highest a* values color stability (p &lt; 0.05) and the lowest rate of myoglobin oxidation (p &lt; 0.05). The level of microbiological contamination of turkey breast meat stored with 100% CO2+ O2scavenger was the lowest. Conditioning breast turkey meat with 100% CO2+ O2scavenger or under vacuum would improve the color stability during storage.

The effect of wholesale vacuum and 100% CO 2 storage on the subsequent microbiological, colour and acceptability attributes of PVC-overwrapped pork loin chops

The shelf life of chops cut from pork loins, after either vacuum or 100% CO 2 storage (0, 7 or 14 days), was determined. The PVC-overwrapped chops were assessed, following a shelf life study of 0, 2, 5 or 7 days at 0 or 5°C, regarding quality attributes such as microbiological contamination levels, colour and acceptability. The study indicated that according to the psychrotrophic counts, the PVC-overwrapped retail chops, from the vacuum as well as the 100% CO 2 stored pork loins (0, 7 or 14 days), still attained a conventional shelf life of 3 days. Lactic acid bacteria and pseudomonads largely represented the psychrotrophic counts. No clear pattern could be detected regarding the colour scores except that the samples displayed at 0°C tended to retain colour longer. These samples were also judged to be more acceptable, although the determination of acceptability was subjective.

Microbiological evaluation of suture items before radiation sterilization.

Microbiological contamination levels of suture samples taken at various stages of the manufacturing process in a new hygienically controlled plant were determined by employing a membrane filturation technique. Both raw material and materials handled manually in the production process were tested to assess the effect of manual handling on the product contamination level. Evaluation of the efficacy of contamination control, however, was directed primarily to the finished, packaged products, just prior to the processing with cobalt 60. The suture material for testing was divided into two groups, namely, wet and dry products, the wet being packaged in a special "tubing" fluid consisting mainly of isopropyl alcohol. Initial contamination results are reported as the average of values obtained on the test day and the preceding 9 consecutive production days. A total of 1,787 suture samples tested in the dry group showed daily averages varying between 2.1 and 14.8 contaminants per suture. The 2,980 wet-packaged suture samples tested gave daily averages varying from 0.7 to 4.2 contaminants per suture. The highest values obtained for an individual suture were 400 for the dry and 89 for the wet. Identification studies of the contaminants revealed that fungi predominated. Most of the bacterial contaminants proved to be spore-forming rods.

Microbiological Evaluation of Suture Items Before Radiation Sterilization

Microbiological contamination levels of suture samples taken at various stages of the manufacturing process in a new hygienically controlled plant were determined by employing a membrane filturation technique. Both raw material and materials handled manually in the production process were tested to assess the effect of manual handling on the product contamination level. Evaluation of the efficacy of contamination control, however, was directed primarily to the finished, packaged products, just prior to the processing with cobalt 60. The suture material for testing was divided into two groups, namely, wet and dry products, the wet being packaged in a special "tubing" fluid consisting mainly of isopropyl alcohol. Initial contamination results are reported as the average of values obtained on the test day and the preceding 9 consecutive production days. A total of 1,787 suture samples tested in the dry group showed daily averages varying between 2.1 and 14.8 contaminants per suture. The 2,980 wet-packaged suture samples tested gave daily averages varying from 0.7 to 4.2 contaminants per suture. The highest values obtained for an individual suture were 400 for the dry and 89 for the wet. Identification studies of the contaminants revealed that fungi predominated. Most of the bacterial contaminants proved to be spore-forming rods.

Microbial Relationship Between the Lesser Mealworm 1 and Its Associated Environment in a Turkey Brooder House 2

This research was designed to investigate microbiological relationships between adult Alphitobius diaperinus (Panzer) and its environment in a turkey brooder house. Insect, litter, and dust samples were collected weekly and cultured on different media to identify bacteria and fungi and to estimate relative levels of microbiological contamination. The number of bacteria and fungi increased during the 13-week sampling period, the amount depending on the type of sample. Surface and subsurface litter became heavily contaminated with bacteria, both having similar bacterial counts. The total number of bacteria in the dust was less than in the litter. The lesser meal worm carried the least. However, a greater percentage of the surface-disinfected lesser mealworms was contaminated with Escherichia coli than any other type sample, and these represented the largest number of the different isolates identified. The lesser mealworm also was the 1st type sample found positive for Salmonella spp. Subsurface litter and dust had the greatest amount of fungi, surface litter was second, while the lesser mealworm had the least amount.