Comprehensive Survey of Pasteurized Fluid Milk Produced in the United States Reveals a Low Prevalence of Listeria monocytogenes

2005 ◽  
Vol 68 (5) ◽  
pp. 973-979 ◽  
Author(s):  
CARY FRYE ◽  
CATHERINE W. DONNELLY
Keyword(s):  
United States ◽  
Listeria Monocytogenes ◽  
The United States ◽  
Assay Method ◽  
Chocolate Milk ◽  
Milk Samples ◽  
Nonfat Milk ◽  
Whole Milk ◽  
Comprehensive Survey ◽  
Fluid Milk

A comprehensive survey was undertaken to generate contemporary data on the prevalence of Listeria monocytogenes in pasteurized fluid milk produced in the United States. Samples (5,519) near the sell-by expiration date were purchased at retail outlets over a 5-week period and analyzed for presence of L. monocytogenes. Products consisted of whole milk, nonfat milk, and chocolate milk packaged in gallon, half gallon, quart, pint, and half-pint containers. Samples were collected from both large and small retail stores in urban and suburban locations in four FoodNet cities (Baltimore, Md., Atlanta, Ga., St. Paul/Minneapolis, Minn., and San Francisco, Calif.). Samples were prescreened for L. monocytogenes by the AOAC-approved rapid Vitek immunodiagnostic assay system, enzyme-linked fluorescent assay method. Positive prescreening samples were cultured according to the Bacteriological Analytical Manual, enumerated for L. monocytogenes with a nine-tube most-probable-number (MPN) procedure, and confirmed by biochemical characterization. The frequency of isolation of L. monocytogenes in these products was 0% (0 of 1,897) in whole milk, 0.05% (1 of 1,846) in nonfat milk, 0% (0 of 1,669) in chocolate milk, and 0% (0 of 107) in other (reduced fat and low fat) milk samples. Overall, L. monocytogenes was confirmed in only 0.018% of pasteurized milk samples (1 of 5,519). Enumeration of the single confirmed positive nonfat milk sample revealed low-level contamination (<0.3 MPN/g), even when sampled 5 days past the expiration of the sell-by date. The results confirm the low frequency of contamination of pasteurized fluid milk products by L. monocytogenes for products sold in the United States and reaffirm the reduction of contamination frequency of fluid milk by L. monocytogenes when compared with earlier estimates from the U.S. Food and Drug Administration Dairy Safety Initiatives Program.

Microflora of Retail Fluid Milk Products1

1977 ◽  
Vol 40 (10) ◽  
pp. 693-697 ◽  
Author(s):  
F. T. JONES ◽  
B. E. LANGLOIS
Keyword(s):  
Clostridium Perfringens ◽  
Skim Milk ◽  
Chocolate Milk ◽  
Milk Products ◽  
Microbial Counts ◽  
Milk Samples ◽  
Whole Milk ◽  
Standard Plate ◽  
Plate Counts ◽  
Fluid Milk

Numbers and types of microorganisms in retail pasteurized fluid milk products were determined as well as the effect that type of product, brand, and season of the year had on counts of 13 different microbial types. Clostridium perfringens was the only pathogen detected and it averaged less than one organism per milliliter. Chocolate milk samples generally had the highest mean counts, followed by skim milk, low-fat (2%), and whole milk (3.25%). Most brands had means for the various microbial counts which were not significantly different from each other. Only three brands had counts which differed significantly from other brands. Psychrotrophic, coliform, staphylococcal, yeast and mold, and Standard Plate Counts were highest between May and October, while counts for spores, streptococci, and thermophiles were highest between December and March. No seasonal trends were detected for counts of anaerobes, C. perfringens, enterococci, or lactobacilli.

Listeria monocytogenes in Raw Milk: Detection, Incidence, and Pathogenicity

1987 ◽  
Vol 50 (3) ◽  
pp. 188-192 ◽  
Author(s):  
J. LOVETT ◽  
D. W. FRANCIS ◽  
J. M. HUNT
Keyword(s):  
United States ◽  
Listeria Monocytogenes ◽  
Sampling Period ◽  
Raw Milk ◽  
The United States ◽  
Isolation Method ◽  
Listeria Species ◽  
Adult Mice ◽  
Listeria Ivanovii

To determine the incidence of Listeria monocytogenes in raw milk, an isolation method was evaluated and used to analyze milk from three areas of the United States. The incidence varied by area from 0% in California to 7% in Massachusetts, with an overall incidence of 4.2%. The highest incidence found in any area during a single sampling period was 12% in Massachusetts in March 1985. During that same sampling, the incidence for all Listeria species was 26%. Of the 27 L. monocytogenes strains isolated during the survey, 25 were pathogenic in adult mice. One of three Listeria ivanovii isolated was pathogenic. No other isolates demonstrated pathogenicity.

Development and Validation of a Dynamic Growth Model for Listeria monocytogenes in Fluid Whole Milk

1999 ◽  
Vol 62 (2) ◽  
pp. 170-176 ◽  
Author(s):  
S. H. ALAVI ◽  
V. M. PURI ◽  
S. J. KNABEL ◽  
R. H. MOHTAR ◽  
R. C. WHITING
Keyword(s):  
Experimental Data ◽  
Listeria Monocytogenes ◽  
Growth Model ◽  
Extreme Values ◽  
Exponential Growth Phase ◽  
Lag Phase ◽  
Maximum Relative Error ◽  
Whole Milk ◽  
Dynamic Growth ◽  
Fluid Milk

Listeria monocytogenes, a psychrotrophic microorganism, has been the cause of several food-borne illness outbreaks, including those traced back to pasteurized fluid milk and milk products. This microorganism is especially important because it can grow at storage temperatures recommended for milk (≤7°C). Growth of L. monocytogenes in fluid milk depends to a large extent on the varying temperatures it is exposed to in the postpasteurization phase, i.e., during in-plant storage, transportation, and storage at retail stores. Growth data for L. monocytogenes in sterilized whole milk were collected at 4, 6, 8, 10, 15, 20, 25, 30, and 35°C. Specific growth rate and maximum population density were calculated at each temperature using these data. The data for growth rates versus temperature were fitted to the Zwietering square root model. This equation was used to develop a dynamic growth model (i.e., the Baranyi dynamic growth model or BDGM) for L. monocytogenes based on a system of equations which had an intrinsic parameter for simulating the lag phase. Results from validation of the BDGM for a rapidly fluctuating temperature profile showed that although the exponential growth phase of the culture under dynamic temperature conditions was modeled accurately, the lag phase duration was overestimated. For an α0 (initial physiological state parameter) value of 0.137, which corresponded to the mean temperature of 15°C, the population densities were under-predicted, although the experimental data fell within the narrow band calculated for extreme values of α0. The maximum relative error between the experimental data and the curve based on an average α0 value was 10.42%, and the root mean square error was 0.28 log CFU/ml.

scholarly journals Fluid milk consumption patterns in the United States, 2003–2004

2007 ◽  
Vol 21 (5) ◽  
Author(s):  
Randy LaComb ◽  
Nancy Raper ◽  
Cecilia W. Enns ◽  
Joseph Goldman ◽  
Alanna J. Moshfegh
Keyword(s):  
United States ◽  
The United States ◽  
Consumption Patterns ◽  
Milk Consumption ◽  
Fluid Milk

Environmental Sustainability of Fluid Milk Delivery Systems in the United States

2017 ◽  
Vol 22 (1) ◽  
pp. 180-195 ◽  
Author(s):  
Jasmina Burek ◽  
Daesoo Kim ◽  
Darin Nutter ◽  
Susan Selke ◽  
Rafael Auras ◽  
...  
Keyword(s):  
United States ◽  
Environmental Sustainability ◽  
The United States ◽  
Delivery Systems ◽  
Fluid Milk

Associations between Bovine, Human, and Raw Milk, and Beef Isolates of Non-O157 Shiga Toxigenic Escherichia coli within a Restricted Geographic Area of the United States

2008 ◽  
Vol 71 (5) ◽  
pp. 1023-1027 ◽  
Author(s):  
R. N. COBBOLD ◽  
M. A. DAVIS ◽  
D. H. RICE ◽  
M. SZYMANSKI ◽  
P. I. TARR ◽  
...  
Keyword(s):  
United States ◽  
Escherichia Coli ◽  
Raw Milk ◽  
Geographic Area ◽  
The United States ◽  
Geographic Region ◽  
Toxin Gene ◽  
Sample Type ◽  
E Coli ◽  
Milk Samples

A survey for Shiga toxigenic Escherichia coli in raw milk and beef was conducted within a defined geographic region of the United States. Prevalence rates based on detection of Shiga toxin gene (stx) were 36% for retail beef, 23% for beef carcasses, and 21% for raw milk samples, which were significantly higher than were Shiga toxigenic E. coli isolation rates of 7.5, 5.8, and 3.2%, respectively. Seasonal prevalence differences were significant for stx positivity among ground beef and milk samples. Distribution of stx subtypes among isolates varied according to sample type, with stx1 predominating in milk, stx2 on carcasses, and the combination of both stx1 and stx2 in beef. Ancillary virulence markers eae and ehx were evident in 23 and 15% of isolates, respectively. Pulsed-field gel electrophoresis demonstrated associations between food isolates and sympatric bovine fecal, and human clinical isolates. These data demonstrate that non-O157 Shiga toxigenic E. coli is present in the food chain in the Pacific Northwest, and its risk to health warrants critical assessment.

Pulsed-field gel electrophoresis applied for comparing Listeria monocytogenes strains involved in outbreaks

1993 ◽  
Vol 39 (4) ◽  
pp. 395-401 ◽  
Author(s):  
C. Buchrieser ◽  
R. Brosch ◽  
B. Catimel ◽  
J. Rocourt
Keyword(s):  
United States ◽  
Listeria Monocytogenes ◽  
Gel Electrophoresis ◽  
The United States ◽  
Pulsed Field Gel Electrophoresis ◽  
Chromosomal Dna ◽  
Restriction Patterns ◽  
Pulsed Field ◽  
Dna Restriction Fragments ◽  
Dna Restriction

Recent food-borne outbreaks of human listeriosis as well as numerous sporadic cases have been mainly caused by Listeria monocytogenes serovar 4b strains. Thus, it was of interest to find out whether a certain clone or a certain few clones were responsible for these cases and especially for outbreaks., We used pulsed-field gel electrophoresis of large chromosomal DNA restriction fragments generated by ApaI, SmaI, or NotI to analyse 75 L. monocytogenes strains isolated during six major and eight smaller recent listeriosis outbreaks. These strains could be divided into 20 different genomic varieties. Thirteen of 14 strains isolated during major epidemics in Switzerland (1983–1987), the United States (California, 1985) and Denmark (1985–1987) demonstrated indistinguishable DNA restriction patterns. In contrast, strains responsible for the outbreaks in Canada (Nova Scotia, 1981), the United States (Massachusetts, 1983), France (Anjou, 1975–1976), New Zealand (1969), and Austria (1986) and some smaller outbreaks in France (1987, 1988, 1989) were each characterized by particular combinations of DNA restriction patterns. Seventy-seven percent of the tested strains could be classified into the previously described ApaI group A (Brosch et al. 1991), demonstrating a very close genomic relatedness. Because 49% of the epidemic strains selected for this study belonged to phagovar 2389/2425/3274/2671/47/108/340 or 2389/47/108/340, fifty-six additional strains of these phagovars, isolated from various origins, were also typed to determine whether differences in DNA restriction profiles between epidemic and randomly selected strains of the same phagovars could be pointed out. Variations in DNA patterns appeared more frequently within randomly selected strains than within epidemic strains.Key words: Listeria monocytogenes, listeriosis, typing, pulsed-field gel electrophoresis, epidemic.

scholarly journals Comprehensive survey of United States internet users’ sentiments towards cryopreservation

PLoS ONE ◽  
2021 ◽  
Vol 16 (1) ◽  
pp. e0244980
Author(s):  
Christopher Robert Gillett ◽  
Taylor Brame ◽  
Emil F. Kendiorra
Keyword(s):  
United States ◽  
Low Temperatures ◽  
The United States ◽  
Fear Of Death ◽  
Cryoprotective Agents ◽  
Internet Users ◽  
Comprehensive Survey ◽  
Attitudes Towards Death ◽  
The Mean ◽  
The Cost

Medical cryopreservation is the speculative practice of using low temperatures and medical-grade cryoprotective agents to halt the decay of a recently-deceased person’s brain and body for the prospect of future resuscitation and restoration of function. We conducted a survey of 1,487 internet users in the United States to measure familiarity with, interest in, beliefs about, and attitudes towards cryopreservation. The majority of respondents (75%) had previously heard of the topic. Respondents tended to underestimate the cost of cryopreservation and number of previous cases but overestimate the number of providers. While many respondents expressed interest in signing up (20%) or had actively researched the topic (21%), a much smaller fraction have decided to be cryopreserved (6%). This level of interest is much greater than the number of previous preservation cases would indicate. We found that respondents’ attitudes towards death significantly correlated with their general sentiments towards the topic, with those expressing a desire for longer life or to see the future being more interested and positively inclined. Fear of death was not associated with interest in cryopreservation. Negative sentiments towards cryopreservation were less common than respondents perceived. For example, 14% of respondents believed that “most people” think cryopreservation should be illegal, but only 4% of respondents actually did. Many respondents (42%) were pessimistic regarding the likelihood of cryopreservation being successful, but the mean estimate of time until revival of cryopreserved bodies would be possible was 82 years.

Sign in / Sign up

Export Citation Format

Share Document