Microbial Evaluation of Selected Fresh Produce Obtained at Retail Markets

2002 ◽  
Vol 65 (4) ◽  
pp. 677-682 ◽  
Author(s):  
RICHARD L. THUNBERG ◽  
TONY T. TRAN ◽  
REGINALD W. BENNETT ◽  
ROGER N. MATTHEWS ◽  
NEGASH BELAY
Keyword(s):  
Fresh Produce ◽  
Agar Plate ◽  
Total Coliform ◽  
Plate Count ◽  
Most Probable Number ◽  
Macconkey Agar ◽  
Salmonella Spp ◽  
Probable Number ◽  
Plate Counts ◽  
Campylobacter Spp

The microbial quality of five types of fresh produce obtained at the retail level was determined by standard quantitative techniques. These techniques included aerobic plate count (APC), total coliform counts, Escherichia coli counts, and yeast and mold counts. Three different methods were used to determine total coliform counts, which consisted of MacConkey agar plate counts, Colicomplete most probable number counts, and Petrifilm E. coli (EC) plate counts. The mean APCs for sprouts, lettuce, celery, cauliflower, and broccoli were 8.7, 8.6, 7.5, 7.4, and 6.3 log10 CFU/g, respectively. MacConkey agar counts indicated that 89 to 96% of the APCs consisted of gram-negative bacteria. Yeast and mold counts were in a range expected of fresh produce. Fresh produce was also analyzed for human pathogens. Samples were analyzed for Staphylococcus spp., Bacillus spp., Salmonella spp., Listeria spp., and Campylobacter spp. One isolate of Staphylococcus was found to be enterotoxigenic, and one species of Bacillus was also toxigenic. Neither Salmonella spp. nor Campylobacter spp. were detected in any of the produce samples. A variety of Listeria spp., including Listeria monocytogenes, were found in fresh produce.

A Microbiological Survey of Three Fresh Green Salads-Can Guidelines be Recommended for these Foods?

1976 ◽  
Vol 39 (2) ◽  
pp. 111-113 ◽  
Author(s):  
JAMES L. FOWLER ◽  
JAMES F. FOSTER
Keyword(s):  
Food Service ◽  
Total Coliform ◽  
Plate Count ◽  
Most Probable Number ◽  
Probable Number ◽  
Military Hospitals ◽  
E Coli ◽  
Total Plate Count ◽  
Plate Counts ◽  
And Staphylococcus Aureus

One hundred samples each of mixed green salad, green salad, and coleslaw were selected from two centralized food service divisions of large military hospitals. Samples were obtained 5 days per week in accordance with production schedules, and were analyzed for total plate count, total coliforms, both plate and Most Probable Number Methods, Escherichia coli, and Staphylococcus aureus. Extremely wide ranges were found in total plate counts and total coliform counts; while confirmed E. coli and S. aureus counts were quite low. The feasibility of establishing microbiological guidelines for these products is discussed.

Levels and Enterotoxigenicity of Clostridium perfringens in Pozole, Tamales, and Birria

2005 ◽  
Vol 68 (2) ◽  
pp. 331-335 ◽  
Author(s):  
V. NAVARRO-HIDALGO ◽  
E. CABRERA-DÍAZ ◽  
H. ZEPEDA ◽  
L. MOTA DE LA GARZA ◽  
A. CASTILLO ◽  
...  
Keyword(s):  
Clostridium Perfringens ◽  
Cell Elongation ◽  
Cytotoxic Effect ◽  
Cell Lysis ◽  
Vero Cells ◽  
Plate Count ◽  
Most Probable Number ◽  
Probable Number ◽  
Quantitative Survey ◽  
Plate Counts

A quantitative survey of Clostridium perfringens in typical foods served at local restaurants was conducted for 18 months in Guadalajara, Mexico. A total of 151 samples, including goat's birria (50), pozole (50), and beef tamales (51), were collected from small restaurants in Guadalajara. Samples were tested for C. perfringens by the most probable number (MPN) method and for mesophilic aerobic plate counts (MAPCs) and coliform, yeast, and mold counts by plate count methods. Isolates confirmed as C. perfringens were further sporulated and tested for cytotoxic or cytotonic effect against Vero cells as an indication of enterotoxin production. C. perfringens was detected in 78 (52%) of all samples at concentrations that ranged from 2.3 to 5.4 log MPN/g. Average MAPCs were 1.3 to 2.7 log CFU/g, depending on the type of dish. Coliform counts ranged from less than 1.0 to 1.5 CFU/g, and yeast and mold counts were less than 1.0 log CFU/g in all cases. A total of 118 isolates of C. perfringens were tested for enterotoxic effect on Vero cells; 82 (70%) showed activity against Vero cells. Of them, 31 isolates induced cell lysis, indicating cytotoxic effect; 41 induced cell elongation, indicating cytotonic effect; and 10 produced both cytotoxic and cytotonic effect. Dilution of the bacterial filtrates that were still producing an effect on Vero cells ranged from 1:80 to 1:5,120. These results underscore the importance of determining enterotoxigenicity when testing for C. perfringens in foods.

scholarly journals Evaluation of Pathogenic Bacteria Associated with Fresh Produce obtained from Selected Markets in Abeokuta

2013 ◽  
Vol 4 (1) ◽  
pp. 75-81
Author(s):  
OR Afolabi ◽  
AR Oloyede ◽  
TA Ibrahim
Keyword(s):  
Escherichia Coli ◽  
Pathogenic Bacteria ◽  
Fresh Produce ◽  
Enterobacter Aerogenes ◽  
Total Coliform ◽  
Shigella Dysenteriae ◽  
Human Consumption ◽  
Salmonella Spp ◽  
Fresh Vegetables ◽  
Plate Counts

The bacterial quality of eight types of fresh produce obtained from selected markets in Abeokuta was determined. Two hundred forty (240) samples of fresh vegetables were examined for aerobic plate counts, coliform counts, and presence of Escherichia coli, toxigenic Staphylococcusaureus, Salmonella spp and Listeria spp. The aerobic plate counts ranged from 2.80 log10 cfu/g to 15.60 log10 cfu/g with the inner parts of cut- water melons having the highest value. Total coliform counts ranged from 0.0 to 11.80 log10 cfu/g. Pathogenic bacteria isolated were Escherichia coli,Staphylococcus aureus, Salmonella spp, Listeria spp, Shigella dysenteriae, Klebsiella pneumoniae, Enterobacter aerogenes, Bacillus spp, Pseudomonas aeruginosa and Streptococcus spp. These pathogens were mostly found at the outer leaves/ parts of the vegetables and render unsafe for human consumption. This study shows that the outer parts/ leaves of fresh produce are heavily contaminated with pathogenic bacteria and the fresh produce should be pre- treated thoroughly, so as to reduce the risk of food- borne outbreaks.Keywords · Pathogenic bacteria · Bacterial quality · Coliform counts

scholarly journals A Microbiological Survey of Selected Alberta-Grown Fresh Produce from Farmers' Markets in Alberta, Canada

2009 ◽  
Vol 72 (2) ◽  
pp. 415-420 ◽  
Author(s):  
V. M. BOHAYCHUK ◽  
R. W. BRADBURY ◽  
R. DIMOCK ◽  
M. FEHR ◽  
G. E. GENSLER ◽  
...  
Keyword(s):  
Foodborne Pathogens ◽  
Fresh Produce ◽  
Farmers Markets ◽  
Most Probable Number ◽  
Urban Centers ◽  
Probable Number ◽  
Public Markets ◽  
E Coli ◽  
Surrounding Areas ◽  
Campylobacter Spp

Previously there was no available information on the levels of indicator bacteria and the prevalence of pathogens in fresh produce grown in Alberta, Canada. Baseline information on the occurrence and levels of Escherichia coli and the prevalence of foodborne pathogens in selected produce items available to consumers from farmers' and public markets in two large urban centers and surrounding areas in Alberta was obtained. A total of 10 large markets with between 1 and 12 produce vendors and 26 small markets with between 1 and 6 produce vendors were sampled from 21 June to 7 October 2007. Lettuce (128 samples), spinach (59 samples), tomatoes (120 samples), carrots (206 samples), green onions (129 samples), and strawberries (31 samples) were analyzed for E. coli, Salmonella, E. coli O157:H7, and Campylobacter spp. Lettuce, spinach, green onion, and strawberry samples were also tested for the presence of Cryptosporidium spp. Information on whether produce was grown using organic or conventional practices was obtained from the produce vendors. E. coli was isolated from 8.2% of the samples that included lettuce, spinach, carrots, and green onions. The bacterial counts ranged from <0.48 to >3.04 Log most probable number per g. E. coli was not isolated from tomatoes or strawberries. The percentage of positive samples ranged from 4.4% for carrots to 27.1% for spinach. Salmonella, E. coli O157:H7, and Campylobacter spp. were not isolated from any of the samples. Cryptosporidium was identified by PCR in one sample of spinach (0.6% of the samples).

Survey of Foodborne Pathogens, Aerobic Plate Counts, Total Coliform Counts, and Escherichia coli Counts in Leafy Greens, Sprouts, and Melons Marketed in the United States

2018 ◽  
Vol 81 (3) ◽  
pp. 400-411 ◽  
Author(s):  
Guodong Zhang ◽  
Yi Chen ◽  
Lijun Hu ◽  
David Melka ◽  
Hua Wang ◽  
...  
Keyword(s):  
United States ◽  
Escherichia Coli ◽  
Foodborne Pathogens ◽  
The United States ◽  
Total Coliform ◽  
Most Probable Number ◽  
Probable Number ◽  
E Coli ◽  
Leafy Greens ◽  
Plate Counts

ABSTRACT The objective of this research was to assess the microbiological status of leafy greens, sprouts, and melons from U.S. markets. A total of 14,183 samples of leafy greens, 2,652 samples of sprouts, and 3,411 samples of melons were collected throughout the United States from 2009 to 2014. The samples were analyzed for aerobic plate counts, total coliform counts, Escherichia coli counts, and the presence and levels of Salmonella, Shigella, Listeria monocytogenes, and Shiga toxin–producing E. coli (STEC), depending on the year and type of produce. Among the leafy greens, no E. coli O157:H7 or non-O157 STEC were detected from iceberg lettuce samples. The overall prevalences of Salmonella, E. coli O157:H7, non-O157 STEC, and L. monocytogenes in the 14,183 samples of leafy greens were 0.05, 0.01, 0.07, and 0.11%, respectively. Among sprout samples, no Salmonella or E. coli O157:H7 was detected, and the overall prevalences of non-O157 STEC and L. monocytogenes were 0.04 and 0.11%, respectively. Among melon samples, no Salmonella was detected from cucumbers, no L. monocytogenes was detected from cantaloupes, and the overall prevalences of Salmonella and L. monocytogenes were 0.12 and 0.23%, respectively. L. monocytogenes levels were 0.4 to 1,470 most probable number (MPN)/g in leafy greens, 0.36 to 1,100 MPN/g in sprouts, and <0.03 to 150 MPN/g in melons, and most positive samples had low levels of these pathogens. The isolates from these foods were very diverse genetically. Foodborne pathogens, including Salmonella, STEC, and L. monocytogenes, had relatively low prevalences in the produce surveyed. Because these foods are usually consumed raw, measures should be taken to significantly minimize the presence and levels of human pathogens.

The Occurrence of Legionella Bacteria in Cooling Towers in South Africa

1991 ◽  
Vol 24 (2) ◽  
pp. 149-152 ◽  
Author(s):  
N. A. Grabow ◽  
E. J. Pienaar ◽  
R. Kfir
Keyword(s):  
South Africa ◽  
Most Probable Number ◽  
Cooling Towers ◽  
Probable Number ◽  
Service Water ◽  
Standard Plate ◽  
Viable Bacteria ◽  
Plate Counts ◽  
High Level ◽  
Biocide Treatment

A total of 510 service water samples from cooling towers throughout South Africa were analysed for the presence of Legionella bacteria. Legionella was detected using an immuno-labelling technique based on the most probable number principle. Only cultural (viable) bacteria were counted. Legionellae were found in most of the samples tested. However, in only 4% of the samples a high level of legionellae was recorded. No correlation was found between the numbers of legionellae and those of standard plate counts. Biocide treatment was shown to be effective in the removal of the bacteria from cooling towers after a 3-month treatment period.

Enumeration of Lactobacillus acidophilus with the Agar Plate Count

1978 ◽  
Vol 41 (6) ◽  
pp. 439-442 ◽  
Author(s):  
E. B. COLLINS
Keyword(s):  
Lactobacillus Acidophilus ◽  
Agar Plate ◽  
Plate Count ◽  
Distilled Water ◽  
Anaerobic Conditions ◽  
Dry Ice ◽  
Standard Methods ◽  
Plate Counts

Higher plate counts on MRS agar were obtained under anaerobic conditions for three of four strains of Lactobacillus acidophilus and commercially prepared nonfermented acidophilus milks (products A and B) made with two of the strains. Average values for aerobic counts of products A and B were 87 and 60%, respectively, of those for corresponding anaerobic counts. Incubation of plates poured with MRS agar for 72 ± 3 h at 37 C was sufficient for maximal counts. Two strains and the nonfermented acidophilus milks gave highest counts on Standard Methods Agar (SMA). Greatest numbers of bile-resistant colonies were indicated by MRS agar (with 0.2% oxgall). The average of plate counts for products A and B determined on MRS agar with oxgall was 65% of that for corresponding plate counts determined on MRS without oxgall. Buffered distilled water, 0.9% NaCl, and 1% peptone each served satisfactorily as diluent. Overlaying MRS agar in poured plates with additional medium was not advantageous. Plate counts of samples that had been frozen and stored at −26 C or in dry ice were as high as those of duplicate samples that had been stored at 1.7 C.

Reduction of Microorganisms on Citrus Fruit Surfaces during Packinghouse Processing

1998 ◽  
Vol 61 (7) ◽  
pp. 903-906 ◽  
Author(s):  
STEVEN PAO ◽  
G. ELDON BROWN
Keyword(s):  
Test Organism ◽  
Citrus Fruit ◽  
Microbial Populations ◽  
Most Probable Number ◽  
Probable Number ◽  
E Coli ◽  
Plate Counts ◽  
High Level ◽  
Inoculation Study ◽  
Fruit Surface

Citrus fruit surface microbial populations were evaluated following various packingline processes of seven Florida commercial packinghouses. At each packinghouse, six fruits (oranges or tangerines) were collected at each of four sampling points. The sampling was conducted in duplicate; thus, 336 fruit were evaluated during this survey. Average aerobic plate counts and yeast and mold counts on fruit surfaces before washing were about 4.0 log CFU/cm2 and 3.3 log CFU/cm2, respectively, and were reduced to 2.1 log CFU/cm2 and 1.3 log CFU/cm2, respectively, by packinghouse processing. Waxing alone reduced the average fruit surface aerobic plate counts and coliform counts from 3.7 log CFU/cm2 and 35.2 most probable number (MPN)/cm2, respectively, to 2.6 log CFU/cm2 and 1.4 MPN/cm2. No Escherichia coli was recovered from fruit at the end of packinghouse processing, and no salmonellae were found on fruit during the entire processing. In an inoculation study to test the effect of packinghouse processes, test organism E. coli was applied to fruit to achieve a high level (4.8 log CFU/cm2) of contamination. The average E. coli count was reduced about 2.4 log cycles by washing and rinsing with potable water (40 psi, 25 °C) for about 30 s. The combination of washing and waxing significantly reduced the inoculated level of E. coli from 4.8 to 1.4 log CFU/cm2.

scholarly journals Kilis İli İçme Sularının Koliform Bakteri Yönünden İncelenmesi

2018 ◽  
Vol 6 (1) ◽  
pp. 65
Author(s):  
Ayşenur Özşavlı ◽  
Figen Şahin ◽  
Mehtap Sadak ◽  
Kıvılcım Çaktü Güler
Keyword(s):  
Drinking Water ◽  
Total Coliform ◽  
Fecal Pollution ◽  
Most Probable Number ◽  
Probable Number ◽  
Public Drinking Water ◽  
Public Drinking ◽  
Different Sources

In this study, fecal pollution was investigated in 6 different sources of public drinking water in Kilis. In the samples taken as seasonal (October, January, April and July) total coliform was tested with the Most Probable Number method. The total number of coliforms detected these source used as drinking water ranged from 3-1100

scholarly journals ESTIMATION OF NUMBERS OF COLIFORM BACTERIAL AS WATER QUALITY INDICATOR IN KEPAHIANG DISTRICT RIVERS, BENGKULU PROVINCE

2021 ◽  
Vol 7 (2) ◽  
pp. 154-163
Author(s):  
Sipriyadi Sipriyadi ◽  
Risky Hadi Wibowo ◽  
Welly Darwis
Keyword(s):  
Water Quality ◽  
Fecal Coliform ◽  
Abiotic Factors ◽  
Total Coliform ◽  
Household Waste ◽  
Most Probable Number ◽  
Abiotic Factor ◽  
Probable Number ◽  
Quality Water ◽  
Ph Range

Coliform is a group of microbes that are used as indicators of water quality. Water pollution is generally caused by pathogenic microbes from feces, household waste, and industrial activity waste. This study aimed to estimate the total number of coliform contamination in several rivers in Kepahiang Regency, namely Tebat Monok (TM), Sempiyang (SPY), Penanjung Panjang (PP), Embong Ijok (EI) Air Langkap(ALK), and Air Belimbing (ABB).  Total coliform and Fecal coliform tests were carried out using the Most Probable Number (MPN) method on Lactose Broth, Brillian Green Lactose Bile Broth and pour plates on Eosin Methylene Blue Agar media. Measurement of abiotic factors was on temperature and pH parameters. The test results of total coliform showed that 6 rivers contained total coliform under the Class II river water quality standards with a range of 1210/100 mL– 4310/100 mL and 2 rivers that were contaminated with Fecal coliform, TM and ALK, have the content of 1500/100 mL and 1700 / 100 mL. The results of the measurement of the abiotic factor, the river pH range was 7.4 - 8.2. The lowest temperature was 25oC in SPY river and the highest temperature was 26 oC on the TM, PP, EI, ALK, and ABB rivers.

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