scholarly journals A minimal apparatus method for counting bacteria: comparison with reference method in surveying beef carcasses at three commercial abattoirs

1983 ◽  
Vol 91 (3) ◽  
pp. 459-466 ◽  
Author(s):  
W. R. Hudson ◽  
T. A. Roberts ◽  
O. P. Whelehan
Keyword(s):  
Reference Method ◽  
The Other ◽  
Bacterial Counts ◽  
Beef Carcasses ◽  
Tile Method

SUMMARYIn two surveys of three commercial abattoirs a minimal apparatus method for making bacterial counts, the ‘loop-tile’ method, detected the same trends in bacterial numbers on beef carcasses as the ISO reference method applied to the same samples. Both methods showed the carcasses from one abattoir, that with an export licence, to carry consistently higher numbers of bacteria, and one of the four sites sampled on each carcass to be consistently dirtier than the other three.

Nutritional Regime, Post-Slaughter Conditioning Temperature, and Vacuum Packaging Effects on Bacteriology of Beef Carcasses and Retail Meat Cuts1

1977 ◽  
Vol 40 (10) ◽  
pp. 678-682 ◽  
Author(s):  
J. D. THOMAS ◽  
D. M. ALLEN ◽  
M. C. HUNT ◽  
C. L. KASTNER
Keyword(s):  
Temperature Treatment ◽  
Vacuum Packaging ◽  
The Other ◽  
Bacterial Counts ◽  
Beef Carcasses ◽  
Conditioning Temperature ◽  
Feeding Regimes ◽  
Retail Meat ◽  
Aerobic And Anaerobic ◽  
Vacuum Storage

Thirty-eight crossbred steers were used to evaluate effects of nutritional regime (grass-, short-, long-, and forage-fed) and post-slaughter chilling (3 C) and conditioning temperature (13 C) on carcass psychrotrophic and mesophilic bacterial counts. Inside chucks from right halves of carcasses chilled at 3 C for 48 h were used to evaluate effects of nutritional regime and vacuum packaging on total aerobic and anaerobic bacterial counts. Psychrotrophic and mesophilic mean bacterial counts tended to decrease from 1 to 46 h postmortem regardless of temperature treatment. At 46 h postmortem, the forage-fed group mean psychrotrophic count was significantly lower (P < 0.05) than that for any of the other feeding regimes. Mesophilic mean counts were significantly different (P < 0.05) at 46 h postmortem (grass-fed >short-fed >long-fed > forage-fed). Carcass halves chilled at 3 C for 46 h had lower total psychrotrophic and mesophilic mean bacterial counts than did corresponding halves conditioned at 13 C for 8 h then chilled at 3 C for 38 h. Total aerobic and anaerobic counts tended to remain constant or decrease slightly during vacuum storage for 21 days at 0 to 1 C. Both aerobic and anaerobic counts on vacuum-stored cuts from carcasses of grass-fed steers were significantly higher (P < 0.05) than other feeding-regime means. Aerobic and anaerobic counts on vacuum-stored cuts from carcasses of short-, long-, and forage-fed steers were statistically similar. All carcass and inside-chuck bacterial counts were well within acceptable limits. Scalpel-template sampling was considered to be a significant improvement over previously used methods.

scholarly journals Diagnostic Performance of Various Methodologies for Group B Streptococcus Screening in Pregnant Woman in China

2021 ◽  
Vol 11 ◽  
Author(s):  
Kankan Gao ◽  
Qiulian Deng ◽  
Lianfen Huang ◽  
Chien-Yi Chang ◽  
Huamin Zhong ◽  
...  
Keyword(s):  
Group B Streptococcus ◽  
Agar Plate ◽  
Reference Method ◽  
Antigen Detection ◽  
The Other ◽  
Blood Agar ◽  
Blood Agar Plate ◽  
Chromogenic Agar ◽  
Group B ◽  
Detection Reagent

Maternal vaginal/rectal colonization of group B streptococcus (GBS) is a main risk for neonatal invasive infection. Efficient determination of GBS colonization in pregnant women is crucial. This study aimed to investigate the prevalence of GBS carriage and evaluate the diagnostic performance of six methodologies for GBS screening conducted in China, including blood agar plate, liquid chromogenic medium, and loop-mediated isothermal amplification (LAMP) without pre-enrichment, chromogenic agar plate with pre-enrichment, and GBS antigen detection without and with pre-enrichment in comparison with the standard reference method (Lim broth-enriched subculture with plating on 5% sheep blood agar). Vaginal/rectal swabs were collected from 1,281 pregnant women at 35–37 weeks of gestation. Of them, 309 were taken in triplicate, one for Lim broth-enriched subculture, one for blood agar plate, and the third for GBS antigen detection (Reagent W); 177 were acquired in duplicate, one for Lim broth-enriched subculture and the other for GBS antigen detection (Reagent H); 502 were obtained in duplicate, one for Lim broth-enriched subculture and the other for liquid chromogenic medium; 158 were collected in duplicate, one for Lim broth-enriched subculture and the other for LAMP; and 135 were inoculated in Lim broth-enriched for GBS antigen detection (Reagent W) and subculture with chromogenic agar plate and 5% blood agar plate. The overall prevalence of GBS carriage was 10.1% (130/1,281, 95% CI: 8.5–12.1%) according to the standard reference method. Compared with the standard reference method, the LAMP had excellent performance of sensitivity (100%, 95%CI: 83.4–100%), specificity (94%, 95%CI: 88.1–97.1%), and Yoden index (0.940); as well as the blood agar plate with sensitivity (81.5%, 95%CI: 61.3–93.0%), specificity (100%, 95%CI: 98.3–100.0%), and Yoden index (0.815). The other four methods were not sufficient to reach the threshold in terms of sensitivity or specificity compared to the standard reference method. Furthermore, for LAMP, results can be obtained within 0.5–1 h, while for blood agar plate, which needed 24–48 h, and further identification was required. Our data suggested that the performance of LAMP was highly comparable to the standard Lim broth-enriched subculture and LAMP is considered as an alternative for fast and accurate GBS screening.

Quantitative Fluorodensitometric Measurement of Aflatoxin B1 with a Flying-Spot Densitometer. II. Comparative Study of B1 Measurements in Spiked and Naturally Contaminated Peanut Products

1972 ◽  
Vol 55 (6) ◽  
pp. 1310-1315
Author(s):  
P R Beljaars ◽  
F H M Fabry ◽  
M M A Pickott ◽  
M J Peeters
Keyword(s):  
Comparative Study ◽  
Silica Gel ◽  
Aflatoxin B1 ◽  
Peanut Butter ◽  
Reference Method ◽  
Amyl Alcohol ◽  
The Other ◽  
Coefficients Of Variation ◽  
Tlc Plates ◽  
Flying Spot

Abstract Peanut butter extracts and samples spiked with 5-40 μg anatoxin B1/kg were analyzed, together with naturally contaminated peanut products, by 3 extraction procedures: the official Dutch method (KB), he Liem et al. method (methanol), and the IUPAC method. The last procedure was selected as a reference method, since it has international application. KB extracts were separated on silica gel G plates with a mixture of chloroform-acetone (90 + 10), whereas IUPAC extracts were separated similarly on MN-G-HR plates. Methanol extracts were resolved on silica gel II plates, using chloroform-trichloroethylene-n-amyl alcohol-formic acid (80 + 15 + 4 + 1) as the developing solvent. After development, plates were scanned with a reflectance flying-spot densitometer. With such techniques, average recoveries for spiked peanut butter extracts ranged from 99 to 105%, with variation values of 11-12%. Recovery values of 69% (KB method) and 84% (methanol and IUPAC methods) were obtained for spiked peanut butter samples. Coefficients of variation ranged from 13 to 15% for fluorodensitometric measurements. Innaturally contaminated peanuts and peanut products , precision values were 13.6% for fluorodensitometric measurements compared to 36% for visual estimations . Both the methanol and IUPAC methods yield extracts suitable for densitometric analysis after spotting on TLC plates; the analytical results obtained are comparable. Extracts from the KB method contained more interfering fluorescent material than the other 2 methods

Bacterial Count from Bovine Carcasses as an Indicator of Hygiene at Slaughtering Places: A Proposal for Sampling

1992 ◽  
Vol 55 (4) ◽  
pp. 271-278 ◽  
Author(s):  
JORGE A. LASTA ◽  
RICARDO RODRÍGUEZ ◽  
MARTA ZANELLI ◽  
CARLOS A. MARGARÍA
Keyword(s):  
Staphylococcus Aureus ◽  
Sampling Technique ◽  
Bacterial Count ◽  
Sampling Plan ◽  
The Other ◽  
Fecal Coliforms ◽  
Sample Unit ◽  
Beef Carcasses ◽  
Polyurethane Sponge ◽  
And Staphylococcus Aureus

A sampling technique by which the whole carcass is rubbed with a polyurethane sponge was used to study bacterial status on 523 beef carcasses at six different slaughterhouses over four different years. Although some abattoirs were differentiated based upon the psychrotroph counts from their carcasses, effects on counts of visits and season of sample taking, as well as interaction year x abattoir found at the other plants were large enough to mask the abattoir effect. Mesophile counts were not consistent enough to discriminate abattoirs, while, Enterobacteria, total and fecal coliforms, and Staphylococcus aureus coagulase-positive organisms showed very low counts and did not set apart differences. A guideline to monitor beef carcass hygiene and indirectely the hygiene of the slaughtering practices through the psychrotroph counts is proposed. A two-kinds sampling plan is suggested with “right-incorrect” as levels of hygiene. A sample unit (n) of 10, an acceptance number of contaminated carcasses (c) of 3, and a count limit (m) of 103 CFU/cm2 are proposed. Under this guideline, a lot of carcasses will be deemed as hygiene lacking when 4 or more, out of 10 carcasses, yield counts of 103 CFU/cm2 or higher.

Laboratory testing protocol to identify critical factors in bacterial compliance monitoring

2003 ◽  
Vol 47 (3) ◽  
pp. 131-136
Author(s):  
M. Abbaszadegan ◽  
P. Ghatpande ◽  
J. Brereton ◽  
A. Alum ◽  
R. Narasimhan
Keyword(s):  
Distribution System ◽  
Membrane Filtration ◽  
Bacterial Count ◽  
The Other ◽  
Residual Chlorine ◽  
First Flush ◽  
Sample Collection ◽  
Service Line ◽  
Bacterial Counts ◽  
Representative Sampling

This research focused on providing guidelines for water utilities on the collection and handling of routine bacteriological samples and in developing scientifically-based approaches in selecting the most representative sampling locations. A laboratory-scale pilot distribution system was designed comprising two parallel loops, one using unlined cast-iron pipe and one using PVC pipe. Each loop contained six sampling ports, including (1) a distribution main dead end faucet, (2) one long (5.5 m; 18 feet) and (3) one short (0.3 m; 1 foot) household copper service line with threaded hose-bibb taps, (4) one hose-bibb with welded faucet, (5) one dedicated sampling port (modeled after a manufacturer’s specifications) and (6) one laboratory-style (PVC) stop-cock sampling port. Residual chlorine concentrations were maintained at 0, 0.5, 1.5 and 2.0 mg/L stages during the course of the experiment. Bacterial samples were collected from the different sampling ports and assayed by membrane filtration and/or spread plate. Nutrient and R2A agars were used for heterotrophic plate counts (HPC), m-Endo agar for total coliform (TC) counts and Chromocult agar for injured bacterial analyses. Several methods of sample collection were tested using various combinations of flushing and tap disinfection, including “first flush” (no flushing, without tap disinfection), flushing only, tap disinfection only (using alcohol or hypochlorite solution) and flushing coupled with tap disinfection. The results indicated that the bacterial counts in samples drawn from dead ends were not significantly different from counts in samples from the other sample port configurations. First flush samples consistently produced the highest bacterial count results. Bacterial counts in samples from the long household copper service line were typically three orders of magnitude higher than in samples from the other sample ports. Thus, there is evidence that long copper household service connections may be unsuitable sample tap configurations for collecting samples intended to represent microbial quality in the distribution system.

scholarly journals Assessment of the Microbial Occupational Work Environment in One Faculty of King Abdulaziz University in Jeddah

2015 ◽  
Vol 26 (2) ◽  
pp. 75-82
Author(s):  
Ahmed Mohamed Moawad Mabrouk Ahmed Mohamed Moawad Mabrouk
Keyword(s):  
Saudi Arabia ◽  
Work Environment ◽  
Indoor Air ◽  
The Other ◽  
Bacterial Counts ◽  
Occupational Environment ◽  
Viable Bacteria ◽  
King Abdulaziz University ◽  
Occupational Work ◽  
Microbial Groups

The presence of microorganisms in indoor air can pose serious health problems so; the purpose of the present work was to monitor the different groups of microorganisms including total viable bacteria, Staphylococci, total coliforms, Salmonella and fungi in different sites of the occupational environment (laboratories, offices, corridors and toilets) inside the Faculty of Metrology, Environment and Arid Land Agriculture, King Abdulaziz University, Jeddah, Saudi Arabia. The results showed that, the average of total viable bacterial counts in different work laboratories was ranged from 9500 to 23000, Staphylococci counts were ranged from 584 to 11000 and fungi counts were ranged from 383 to 2500 cfu/m3. On the other hand the total viable bacterial counts in work offices varied from 12700 to 26500 cfu/m3, meanwhile Staphylococci counts ranged from 5000 to 9500 cfu/m3 and fungi counts ranged from 1500 to 4833 cfu/m3. Also, the total viable bacterial counts in corridors ranged from 14340 to 23700 cfu/m3, Staphylococci counts ranged from 3167 to 10340 cfu/m3 and fungi counts ranged from 2830 to 5165 cfu/m3. Finally, the average of the total viable bacterial counts in toilets reached 22833 cfu/m3. Meanwhile, Staphylococci counts were 4920 cfu/m3 and fungi counts were 3010 cfu/m3. The highest average of total viable bacterial counts were found in toilets (22833 cfu/m3), the highest average of Staphylococci counts recorded (7811 cfu/m3) in corridors and the highest average of fungi counts were observed in laboratories (4516 cfu/m3). It is clear that the toilets had the highest average of total viable bacterial counts, the corridors had the highest average of Staphylococci counts and laboratories had the highest average of fungi. The microbial groups of coliforms, yeasts and Salmonella were not detected in all sampling sites (laboratories, offices, corridors and toilets). Finally, an attention must be given in the place to protect and enhance the occupational environment and keep health of students and workers well.

scholarly journals Comparison of different methods for the determination of total organic carbon and humic substances in Brazilian soils

Revista CERES ◽  
2015 ◽  
Vol 62 (5) ◽  
pp. 496-501 ◽  
Author(s):  
Raphael Bragança Alves Fernandes ◽  
Ildeu Afonso de Carvalho Junior ◽  
Emerson Silva Ribeiro Junior ◽  
Eduardo de Sá Mendonça
Keyword(s):  
Reference Method ◽  
Soil Samples ◽  
The Other ◽  
Loss On Ignition ◽  
Oxidation Method ◽  
External Heating ◽  
Humin Fraction ◽  
Humic Fractions ◽  
Dry Combustion

ABSTRACTAiming to compare three different methods for the determination of organic carbon (OC) in the soil and fractions of humic substances, seventeen Brazilian soil samples of different classes and textures were evaluated. Amounts of OC in the soil samples and the humic fractions were measured by the dichromate-oxidation method, with and without external heating in a digestion block at 130 °C for 30 min; by the loss-on-ignition method at 450 °C during 5 h and at 600 °C during 6 h; and by the dry combustion method. Dry combustion was used as reference in order to measure the efficiency of the other methods. Soil OC measured by the dichromate-oxidation method with external heating had the highest efficiency and the best results comparing to the reference method. When external heating was not used, the mean recovery efficiency dropped to 71%. The amount of OC was overestimated by the loss-on-ignition methods. Regression equations obtained between total OC contents of the reference method and those of the other methods showed relatively good adjustment, but all intercepts were different from zero (p < 0.01), which suggests that more accuracy can be obtained using not one single correction factor, but considering also the intercept. The Walkley-Black method underestimated the OC contents of the humic fractions, which was associated with the partial oxidation of the humin fraction. Better results were obtained when external heating was used. For the organic matter fractions, the OC in the humic and fulvic acid fractions can be determined without external heating if the reference method is not available, but the humin fraction requires the external heating.

Determination of the Principal Points of Product Contamination during Beef Carcass Dressing Processes in Northern Ireland

2004 ◽  
Vol 67 (7) ◽  
pp. 1494-1496 ◽  
Author(s):  
ROBERT H. MADDEN ◽  
KATHRYN A. MURRAY ◽  
ARTHUR GILMOUR
Keyword(s):  
Northern Ireland ◽  
Control Point ◽  
Microbiological Quality ◽  
Sampling Point ◽  
Bacterial Counts ◽  
Critical Control Point ◽  
Beef Carcasses ◽  
Principal Points ◽  
Incubation Temperatures ◽  
Beef Carcass

To determine the principal points of microbial contamination of carcasses during beef carcass dressing in Northern Ireland, 190 carcasses were sampled by swabbing 1,000 cm2 of the brisket. A detailed survey of one abattoir was initially conducted, with sampling of a total of 100 carcasses immediately after hide removal (H), after carcass splitting (S), and immediately after washing (W) before dispatch to the chiller. The total bacterial counts after incubation at both 22 and 37°C indicated that there was no significant increase in the numbers of bacteria after the first sampling point, H (P &gt; 0.05). To determine whether this was the case in the majority of Northern Ireland abattoirs, 15 carcasses were then sampled at each of an additional six abattoirs, at points H and W only. Total bacterial counts were significantly higher (P &lt; 0.05) at H than at W, indicating that hide pulling was the major point of bacterial contamination of beef carcasses and hence a critical control point for the final microbiological quality of the carcasses. Mean counts of Enterobacteriaceae at both incubation temperatures were very low (&lt;10 CFU/cm2) but were higher at W than at H, probably indicating that washing was redistributing bacteria from the posterior to the anterior region.

Steam Vacuuming as a Pre-Evisceration Intervention To Decontaminate Beef Carcasses

1997 ◽  
Vol 60 (2) ◽  
pp. 107-113 ◽  
Author(s):  
SHERRI L. KOCHEVAR ◽  
JOHN N. SOFOS ◽  
ROBERT R. BOLIN ◽  
JAMES O. REAGAN ◽  
GARY C. SMITH
Keyword(s):  
Fecal Contamination ◽  
Total Coliform ◽  
Processing Plant ◽  
Bacterial Counts ◽  
Microbial Counts ◽  
Beef Carcasses ◽  
Processing Plants ◽  
Plate Counts ◽  
Experimental Treatments ◽  
Unit Unit

One steam-vacuuming unit (Unit A) was evaluated for removal of visible contamination and reduction of bacterial counts on beef carcass surfaces in five processing plants; a second steam-vacuuming unit (Unit B) was evaluated in two of those same plants at a later date. Experimental treatments included appropriate Controls: steam vacuuming carcass surfaces with or without visible contamination, and knife trimming surfaces with visible contamination. Depending on the processing plant, carcasses were tested on the midline or on the round. Each treatment was applied to a 103-cm2 area of the carcass surface, which was scored for visible contamination and analyzed for aerobic plate counts (APC) at 25°C and for total coliform counts (TCC). Average reductions in APC of 0.57 (Unit A) and 0.72 (Unit B) log CFU/cm2 and in TCC of 0.33 (Unit A) and 0.26 (Unit B) log CFU/cm2 were obtained by steam-vacuuming carcass surfaces which had no visible fecal contamination. Steam vacuuming and knife trimming effectively (P &lt; 0.05) cleaned soiled carcass surfaces and reduced microbial counts. Knife trimming reduced APC and TCC by 1.38 and 1.61 log CFU/cm2 in the Unit A experiment and by 1.64 and 1.72 log CFU/cm2 in the Unit B experiment, respectively. Steam vacuuming carcass surfaces soiled with visible contamination reduced APC and TCC by 1.73 and 1.67 log CFU/cm2 (Unit-A) and by 2.03 and 2.13 log CFU/cm2 (Unit B), respectively. The results of this study suggest that both steam-vacuuming systems available at the time of the study were at least as effective as knife trimming in decontaminating beef carcasses with areas of visible contamination 2.54 cm in the greatest dimension.

Risk of Salmonellosis Associated with Consumption of Chocolate in Mexico

1995 ◽  
Vol 58 (5) ◽  
pp. 478-481 ◽  
Author(s):  
MA. REFUGIO TORRES-VITELA ◽  
EDUARDO F. ESCARTIN ◽  
ALEJANDRO CASTILLO
Keyword(s):  
Potential Risk ◽  
Brilliant Green ◽  
The Other ◽  
Salmonella Spp ◽  
Bacterial Counts ◽  
Nonfat Milk ◽  
Other Hand ◽  
Infective Dose ◽  
Enrichment Methods

To assess the potential risk of salmonellosis associated with consumption of chocolate, the prevalence of Salmonella spp. was investigated in retail wrapped and nonwrapped solid chocolate in Guadalajara, Mexico. Previously, the efficiency of preenrichment and enrichment methods to isolate low numbers of Salmonella in chocolate was compared. Though not completely efficient, a preenrichment in nonfat milk without brilliant green, followed by enrichment in tetrathionate and selenite cystine broths gave better results than the other methods studied. Regarding the survey of retail chocolate, Salmonella was isolated from 2 (4.5%) of 44 samples of wrapped chocolate and from none of 56 samples of nonwrapped chocolate. The serovars identified were Salmonella agona and Salmonella derby. There were no significant differences between coliform counts or total bacterial counts obtained from wrapped and nonwrapped chocolate. The presence of Salmonella in chocolate is of concern due to the several low-infective-dose Salmonella outbreaks that have been linked to chocolate. On the other hand, a technique capable of detecting low numbers of Salmonella in chocolate is still needed.

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