Fw: [BITES-L] bites Dec. 3/10 -- II
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Subject: [BITES-L] bites Dec. 3/10 -- II
bites Dec. 3/10 -- II
E. coli O157:H7 survives long past 60 days in manufacture and aging of gouda; more evidence
NEVADA: Dirty dining: La Mexicana Market
UK: Agency announces review of official controls delivery
US: Vaccine use up since Salmonella outbreak
Transfer of Listeria innocua from contaminated compost and irrigation water to lettuce leaves
Tracking the Salmonella status of pigs and pork from Lairage through the slaughter process in the Republic of Ireland
Validation of lactic acid bacteria, lactic acid, and acidified sodium chlorite as decontaminating interventions to control Escherichia coli O157:H7 and Salmonella typhimurium DT 104 in mechanically tenderized and brine-enhanced (nonintact) beef at the purveyor
Inoculation of beef with low concentrations of Escherichia coli O157:H7 and examination of factors that interfere with its detection by culture isolation and rapid methods
Inactivation kinetics and virulence potential of Salmonella typhimurium and Listeria monocytogenes treated by combined high pressure and nisin
Determination of the viability of Toxoplasma gondii in cured ham using bioassay: Influence of technological processing and food safety implications
Reduction of Salmonella enterica contamination on grape tomatoes by washing with thyme oil, thymol, and carvacrol as compared with chlorine treatment
Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 11. use of antiseptics and sanitizers in community settings and issues of hand hygiene compliance in health care and food industries
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E. coli O157:H7 survives long past 60 days in manufacture and aging of gouda; more evidence
03.dec.10
barfblog
Doug Powell
http://www.barfblog.com/blog/145471/10/12/03/e-coli-o157h7-survives-long-past-60-days-manufacture-and-aging-gouda-more-evide
D'Amico et al., report in the current Journal of Food Protection "that the 60-day aging requirement alone is insufficient to completely eliminate levels of viable E. coli O157:H7 in Gouda or stirred-curd Cheddar cheese manufactured from raw milk contaminated with low levels of this pathogen."
Bet Costco would have liked to know that before the outbreak linked to Gouda that has sickened at least 37 people in five U.S. states.
The complete abstract is below.
Behavior of Escherichia coli O157:H7 during the manufacture and aging of gouda and stirred-curd cheddar cheeses manufactured from raw milk
01.dec.10
Journal of Food Protection
D'Amico, Dennis J.; Druart, Marc J.; Donnelly, Catherine W.
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00009
Abstract:
This study was conducted to examine the fate of Escherichia coli O157:H7 during the manufacture and aging of Gouda and stirred-curd Cheddar cheeses made from raw milk. Cheeses were manufactured from unpasteurized milk experimentally contaminated with one of three strains of E. coli O157:H7 at an approximate population level of 20 CFU/ml. Samples of milk, whey, curd, and cheese were collected for enumeration of bacteria throughout the manufacturing and aging process. Overall, bacterial counts in both cheese types increased almost 10-fold from initial inoculation levels in milk to approximately 145 CFU/g found in cheeses on day 1. From this point, counts dropped significantly over 60 days to mean levels of 25 and 5 CFU/g in Cheddar and Gouda, respectively. Levels of E. coli O157:H7 fell and stayed below 5 CFU/g after an average of 94 and 108 days in Gouda and Cheddar, respectively, yet remained detectable after selective enrichment for more than 270 days in both cheese types. Changes in pathogen levels observed throughout manufacture and aging did not significantly differ by cheese type. In agreement with results of previous studies, our results suggest that the 60-day aging requirement alone is insufficient to completely eliminate levels of viable E. coli O157:H7 in Gouda or stirred-curd Cheddar cheese manufactured from raw milk contaminated with low levels of this pathogen.
http://barfblog.foodsafety.ksu.edu/blog/145135/10/11/16/health-officials-confirm-e-coli-cheese-samples
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00009
NEVADA: Dirty dining: La Mexicana Market
02.dec.10
KTNV
http://www.ktnv.com/story/13591395/dirty-dining-la-mexicana-market
Las Vegas, NV -– Improperly stored food, issues with kitchen tools, and filthy conditions are not things normally advertised on a restaurant menu.
But they were found at La Mexicana Market on East Charleston near Maryland Parkway.
A recent visit by the Southern Nevada Health District uncovered some major violations that added up to 52 demerits, prompting the closure of the market's restaurant, deli, and bakery.
Anything more than 40 demerits results in an automatic closures by the health district.
Inside the restaurant's walk-in cooler inspectors found food such as chicken, rice, and garlic stored at the incorrect temperature. Deli meats and raw bacon were also not kept refrigerated and were described as "discolored" with a spoiled smell.
There were also issues with equipment: Layers of food debris were seen on a can opener, lemon juicer, and all of the bakery equipment – some of which was also being stored with clean equipment and utensils.
There was also "pink and slimy debris" found inside the ice machine and on the soda machine; the floors and ceiling were noted as being dirty; and inspectors say they observed the re-using of single-use aluminum trays and Styrofoam cups.
Channel 13's Tricia Kean spoke with the market's owner, Joe, who only agreed to talk if his face wasn't shown on camera. He says he just recently bought La Mexicana Market.
"When we took this, over it was a horrible mess."
Joe says he was in the process of cleaning up the establishment when the health district showed up for an inspection.
UK: Agency announces review of official controls delivery
03.nov.10
Food Standards Agency
http://www.food.gov.uk/news/newsarchive/2010/dec/officialcontrols
The Chief Executive of the Food Standards Agency Tim Smith has today announced a review of how food safety regulations are enforced in the UK.
Speaking at a conference on food safety, organised by the FSA and the Chartered Institute of Environmental Health, Tim Smith said the FSA was looking for new ways of making the system of enforcing food safety regulations more efficient. Any new approach, he added, would have to offer the best protection for consumers.
Tim Smith said: 'The Food Standards Agency is responsible for the controls on food in the UK, but the enforcement is currently done in different ways: by employees of the FSA, by other government departments, by contractors and by local authorities. This system can be complex and in the current climate of increased financial pressures it is timely to consider how we can secure better efficiency, consistency, and resilience in this vital area of public health protection. Our goal will be to ensure that the system we have in place is the best way of protecting consumers.
'This review follows a request by the First Minister for Wales asking the Agency to carry out a review of food law enforcement in Wales. He asked if consumers in Wales are adequately protected and wanted us to evaluate other possible models of delivering food law enforcement. Today I'm proposing we should build on the work that the FSA in Wales is already doing and extend our evaluation to the whole of the UK.'
The review will see the Agency working closely with the food industry, local authorities, and professional bodies like the Chartered Institute of Environmental Health in considering alternative approaches to enforcement that will offer the best protection for consumers. The review will cover all four countries of the UK.
US: Vaccine use up since Salmonella outbreak
03.dec.10
AVMA
http://www.avma.org/onlnews/javma/dec10/101215x.asp
This summer's nationwide Salmonella outbreak and related egg recall are likely drivers of a recent rise in the use of Salmonella enteritidis vaccines.
Gary Baxter, marketing director for CEVA Biomune, which produces poultry-use Salmonella vaccines, said market research indicates about 60 percent of egg producers were vaccinating their flocks against S enteritidis at the end of 2009, but he estimated about 78 or 79 percent of producers were vaccinating by November 2010. At least 15 percent of the industry diverts all its eggs for pasteurization, and he expects industry members are close to universally adopting vaccination.
While vaccine use has increased in each of the past five years, Baxter said the recent illnesses and new Food and Drug Administration regulations related to microbial testing and control were both likely causes of the substantial jump in flock vaccination rates. He said his company produces most of the nation's poultry-use S enteritidis vaccine.
Two Iowa-based egg producers, Wright County Egg and Hillandale Farms of Iowa Inc., issued nationwide recalls for more than 500 million eggs after investigations by state and federal health officials indicated the two farms were likely the source of shell eggs connected with more than 1,800 illnesses nationwide during the outbreak, according to information from the Centers for Disease Control and Prevention and the FDA.
About one year prior to the outbreak's peak, the FDA had announced new rules intended to reduce Salmonella-related illnesses. The rules took effect July 9 and include requirements that egg producers have written S enteritidis prevention plans and conduct contamination tests.
Coinciding influences on vaccine use
Dr. David J. Henzler, a consultant for the poultry industry, said veterinarians and egg producers have successfully used vaccines to reduce Salmonella shedding, particularly when the vaccines were administered prior to molting and used along with prevention methods such as effective rodent control and screening of the chicks and pullets entering flocks. While the FDA regulations that took effect in July 2010 could additionally reduce the risk of Salmonella outbreaks, he does not think the changes were in place and enforced quickly enough to prevent the summer outbreak.
Dr. Henzler said he has worked with both companies involved in the recall, but he was not familiar with their vaccine programs. However, he said egg industry members individually decide which methods are worth their costs, and he noted that publicly traded egg-producing companies are particularly aware of the risks posed by foodborne illness outbreaks.
Dr. Darrell Trampel, an extension poultry veterinarian and poultry diagnostician in the Iowa State University College of Veterinary Medicine, thinks the 2010 Salmonella outbreak served as a wake-up call for the egg industry.
"I think the long-term effect of this outbreak is going to be a safer egg supply," Dr. Trampel said.
Some producers who vaccinate their chickens administer live vaccines consisting of gene-deleted attenuated S enterica serovar Typhimurium within the first few days after hatching and again when the chickens are about four weeks old. Live vaccines can be administered along with, or instead of, vaccines that contain killed S enteritidis bacteria; the killed vaccines are usually given when the chickens are between 13 and 15 weeks old.
"Vaccination is not 100 percent effective, but it is a very useful tool to control Salmonella enteritidis in chickens," Dr. Trampel said. "It's important, and my recommendation is that all egg producers use both live and killed vaccines."
Dr. Charles L. Hofacre, secretary and treasurer for the American Association of Avian Pathologists, also recommended use of both attenuated live and inactivated vaccines.
He said vaccination was also increasing in the broiler industry, but vaccination rates remained higher in the egg industry. In addition to vaccination, producers should also implement rodent control, insect control, and biosecurity measures to reduce contamination, he said.
While vaccination can involve a substantial investment, particularly among large-scale egg producers, Dr. Hofacre thinks many producers want the economic fairness that would come from a requirement that all hens be vaccinated. He estimates that it costs producers about 18 cents to vaccinate each hen, and producers do not benefit directly from that "insurance policy" as they do with use of vaccines that improve hen health.
However, with the increased use of S enteritidis vaccines and other control measures, Dr. Hofacre expects a reduction in foodborne illnesses and outbreaks and increased consumer confidence.
Voluntary action with encouragement
Gene Gregory, president and CEO of United Egg Producers, said his organization has twice in the past six years urged FDA officials to provide incentives for vaccine use.
"We believe vaccines are an important component of food safety programs," Gregory said.
In a Sept. 10 letter to the FDA, Gregory indicated that the UEP supports FDA regulations intended to prevent S enteritidis contamination in eggs, but the organization thinks it is imperative to take additional steps to further reduce the risk of contamination and strengthen public confidence in regulators and producers.
"Therefore, we respectfully urge the FDA to make SE vaccination an integral part of producer compliance with your regulations, and to do so in a manner that will ensure universal adoption of vaccination programs," the letter states.
The letter states that experiences of members who have implemented vaccination programs and colleagues in the United Kingdom, "where such programs are effectively mandatory," have led the UEP to conclude that it is important to vaccinate all hens.
Gregory's letter advocates that the FDA amend its S enteritidis guidance document to state that all producers should add vaccination to their plans, which will avoid delays under the regulatory process and influence nearly all producers who are not currently vaccinating hens to adopt vaccination programs.
Gregory said in a message that, out of consideration for small-scale egg producers, his organization did not ask for mandatory vaccination. The FDA considered requiring use of S enteritidis vaccines as part of a proposed egg safety rule issued in 2004, but agency officials determined that they did not have enough evidence to add such a requirement. But FDA officials said in late August they were working with the Department of Agriculture to review data on Salmonella vaccines and "determine whether additional recommendations or requirements are appropriate."
Gerardo A. Ramirez, PhD, a consumer safety officer with the FDA Center for Food Safety and Applied Nutrition, is examining the effectiveness and availability of poultry-use vaccines. He said that, when the 2004 egg safety rule was drafted, the agency particularly wanted more evidence from studies involving real-world settings as opposed to laboratory conditions. The FDA is reexamining the issue and could make decisions ranging from upholding existing regulations and guidance without changes to requiring vaccine use.
However, Dr. Ramirez stressed that the agency has not made any decisions and is considering all scientific evidence and literature located so far while searching for additional evidence. Agency spokeswoman Laura Alvey added that the FDA would seek public comments if any changes were proposed.
Dr. Ramirez said his research has shown a broad range of efficacy across vaccine applications. Effective vaccines could be one part of Salmonella control, but he hopes nobody mistakenly believes vaccination could replace biosecurity, pest control, and disinfection practices.
Cindy Ragin, a spokeswoman for the USDA Animal and Plant Health Inspection Service, said the USDA's S enteritidis working group was evaluating the efficacy of vaccines in determining whether to recommend that the FDA require vaccination. The department has provided data to the FDA, and APHIS' evaluation was ongoing.
Transfer of Listeria innocua from contaminated compost and irrigation water to lettuce leaves
03.nov.10
Food Microbiology
M. Oliveira, J. Usall, I. Viñas, C. Solsona and M. Abadias
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WFP-51M0N8X-1&_user=10&_coverDate=12%2F02%2F2010&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=926fcbe23372e327d45205ef35239364&searchtype=a
Abstract
Many foodborne outbreaks of some pathogens such as Escherichia coli O157:H7, Salmonella or Listeria have been associated with the consumption of contaminated vegetables. Contaminated manure and polluted irrigation water are probable vehicles for the pathogens. The aim of this study was to determine the potential transfer of Listeria innocua from soil fertilized with contaminated compost or irrigated with contaminated water to the edible parts of lettuce grown on these soils together with its survival in lettuce and in soil under field conditions during two different seasons. Moreover, its survival on lettuce sprinkled with contaminated irrigation water was evaluated. L. innocua survived in soil samples for 9 weeks at high concentrations, 105 cfu gdw-1 in fall and 103 cfu gdw-1 in spring. Pathogen survived better in fall, indicating an important influence of temperature and humidity. L. innocua population in lettuce leaves was very high on lettuce leaves after sprinkling, but decreased to undetectable levels at field conditions. There was also transfer of L. innocua from soil contaminated with compost or irrigated with contaminated water to lettuce leaves, mainly to the outer ones. Survival profiles of L. innocua on lettuce and soil samples contaminated either by application of contaminated compost or surface irrigation water was similar. Our results indicated that contaminated compost and contaminated irrigation water can play an important role in the presence of foodborne pathogens on vegetables.
Tracking the Salmonella status of pigs and pork from Lairage through the slaughter process in the Republic of Ireland
01.dec.10
Journal of Food Protection
Duggan, S.J.; Mannion, C.; Prendergast, D.M.; Leonard, N.; Fanning, S.; Gonzales-Barron, U.; Egan, J.; Butler, F.; Duffy, G.
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00001
Abstract:
Salmonella Typhimurium is the predominant serotype isolated from humans in Europe. Pork and pork products are recognized vehicles of Salmonella and are responsible for outbreaks of human salmonellosis. Pigs can become infected with Salmonella on the breeding or fattening farm and during transport, lairage, and slaughter. The aim of this study was to investigate selected points of Salmonella contamination from the time pigs entered the lairage to the time the carcass was processed in the boning hall and to determine the importance of different sources of Salmonella along the Irish pork production chain. A second objective was to evaluate whether the serological status or category of a herd influenced the levels of bacteriological contamination detected on individual carcasses and pork cuts during slaughter and dressing operations. All samples were tested for the presence and numbers of Salmonella. Enterobacteriaceae numbers were also determined. Serotype, phage type, and pulsed-field gel electrophoresis were utilized to determine similarity among Salmonella isolates. Lairage was a major source of cross-contamination with Salmonella as were the hands of evisceration operatives, conveyor belts, and equipment in the boning hall. Cross-contamination within the slaughter plant environment accounted for up to 69 % of Salmonella carcass contamination. In general, herd category reflected the bacteriological status of carcasses and pork cuts. Major findings were a strong association (P < 0.01) between Enterobacteriaceae counts and Salmonella occurrence on prechill carcasses and a significant association (P < 0.05) between Enterobacteriaceae counts and Salmonella occurrence on pork cut samples.
Validation of lactic acid bacteria, lactic acid, and acidified sodium chlorite as decontaminating interventions to control Escherichia coli O157:H7 and Salmonella typhimurium DT 104 in mechanically tenderized and brine-enhanced (nonintact) beef at the purveyor
01.dec.10
Journal of Food Protection
Echeverry, Alejandro; Brooks, J. Chance; Miller, Markus F.; Collins, Jesse A.; Loneragan, Guy H.; Brashears, Mindy M.
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00003
Abstract:
After three different outbreaks were linked to the consumption of nonintact meat products contaminated with Escherichia coli O157:H7, the U.S. Food Safety and Inspection Service published notice requiring establishments producing mechanically tenderized and moisture-enhanced beef products to reassess their respective hazard analysis and critical control point systems, due to potential risk to the consumers. The objective of this study was to validate the use of lactic acid bacteria (LAB), acidified sodium chlorite (ASC), and lactic acid (LA) sprays when applied under a simulated purveyor setting as effective interventions to control and reduce E. coli O157:H7 and Salmonella Typhimurium DT 104 in inoculated U.S. Department of Agriculture (USDA) Choice strip loins (longissimus lumborum muscles) pieces intended for either mechanical blade tenderization or injection enhancement with a brine solution after an aging period of 14 or 21 days at 4.4°C under vacuum. After the mechanical process, translocation of E. coli O157:H7 and Salmonella Typhimurium DT 104 from the surface into the internal muscles occurred at levels between 1.00 and 5.72 log CFU/g, compared with controls. LAB and LA reduced internal E. coli O157:H7 loads up to 3.0 log, while ASC reduced the pathogen 1.4 to 2.3 log more than the control (P < 0.05), respectively. Salmonella Typhimurium DT 104 was also reduced internally 1.3 to 2.8, 1.0 to 2.3, and 1.4 to 1.8 log after application of LAB, LA, and ASC, respectively. The application of antimicrobials by purveyors prior to mechanical tenderization or enhancement of steaks should increase the safety of these types of products.
Inoculation of beef with low concentrations of Escherichia coli O157:H7 and examination of factors that interfere with its detection by culture isolation and rapid methods
01.dec.10
Journal of Food Protection
Bosilevac, Joseph M.; Kalchayanand, Norasak; Schmidt, John W.; Shackelford, Steven D.; Wheeler, Tommy L.; Koohmaraie, Mohammad
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00004
Abstract:
Currently used industry testing programs require the ability to detect Escherichia coli O157:H7 in samples of beef trim or ground beef at levels as low as 1 CFU/375 g. We present a reliable protocol for generating a control inoculum for verification testing at this low concentration and evaluate its use. Results show that half of all samples received no cells when 1 CFU was the target concentration and that targets greater than 3 CFU were much more reliable. Detection by culture isolation and two commercial assays, Qualicon BAX-MP and BioControl GDS, detected 94% ± 11%, 92% ± 10%, and 92% ± 7% of samples inoculated with 5.4 CFU (range 1 to 9 CFU), respectively. We also examined the effect of background aerobic plate count (APC) bacteria and fat content effects on the detection of E. coli O157:H7. At APC concentrations below 6 log CFU/g, the rapid methods detected all beef trim samples inoculated with 26 CFU of E. coli O157:H7 per 65 g. At an APC of 6.7 log CFU/g, culture, BAX-MP, and GDS detected 100, 75, and 13%, respectively, of inoculated samples. Neither commercial method detected E. coli O157:H7 in the samples when APC was 7.7 log CFU/g, whereas culture was able to detect 63% of E. coli O157:H7 in the samples when APC was at this concentration. Increased fat content correlated with decreasing recovery of immunomagnetic separation beads, but this was not observed to interfere with detection of E. coli O157:H7.
Inactivation kinetics and virulence potential of Salmonella typhimurium and Listeria monocytogenes treated by combined high pressure and nisin
01.dec.10
Journal of Food Protection
Gou, Jingyu; Lee, Hyeon-Yong; Ahn, Juhee
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00007
Abstract:
The aim of this study was to characterize the physiological and molecular changes of Salmonella Typhimurium and Listeria monocytogenes in deionized water (DIW) and nisin solutions (100 IU/g) during high pressure processing (HPP). Strains of Salmonella Typhimurium and L. monocytogenes in DIW or nisin solutions were subjected to 200, 300, and 400 MPa for 20 min. The Weibull model adequately described the HPP inactivation of Salmonella Typhimurium and L. monocytogenes. Salmonella Typhimurium and L. monocytogenes populations were reduced to less than 1 CFU/ml in DIW and nisin solutions under 400 MPa. The highest b value was 5.75 for Salmonella Typhimurium in nisin solution under 400 MPa. L. monocytogenes was more sensitive to pressure change when suspended in DIW than when suspended in nisin. The pressure sensitivity of both Salmonella Typhimurium and L. monocytogenes was higher in DIW solution (141 to 243 MPa) than in nisin solution (608 to 872 MPa). No recovery of HPP-injured cells in DIW and nisin solutions treated at 400 MPa was observed after 7 days of refrigerated storage. The heterogeneity of HPP-treated cells was revealed in flow cytometry dot plots. The transcripts of stn, invA, prfA, and inlA were relatively down-regulated in HPP-treated nisin solution. The combination of high pressure and nisin could noticeably suppress the expression of virulence-associated genes. These results provide useful information for understanding the physiological and molecular characteristics of foodborne pathogens under high-pressure stress.
Determination of the viability of Toxoplasma gondii in cured ham using bioassay: Influence of technological processing and food safety implications
01.dec.10
Journal of Food Protection
Bayarri, Susana; Gracia, María J.; Lázaro, Regina; Pe´rez-Arquillué, Consuelo; Barberán, Montserrat; Herrera, Antonio
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00012
Abstract:
Toxoplasmosis is a zoonotic disease caused by the protozoan Toxoplasma gondii and distributed worldwide. Ingestion of viable cysts from infected raw or undercooked meat is an important route of horizontal transmission of the parasite to humans. Little information is available concerning the effect of commercial curing on cysts of T. gondii. This study is the first in which the influence of processing of cured ham on the viability of T. gondii has been evaluated, using bioassay to assess the risk of infection from eating this meat product. Naturally infected pigs were selected for the study, and a mouse concentration bioassay technique was used to demonstrate viable bradyzoites of T. gondii in porcine tissues and hams. No viable parasites were found in the final product (14 months of curing) based on results of the indirect immunofluorescence assay and histological and PCR analyses. Our results indicate that the consumption of hams cured as described here poses an insignificant risk of acquiring toxoplasmosis. However, additional studies are required to evaluate the safety of ham products cured under different conditions of curing time, salt, and nitrite concentration.
Reduction of Salmonella enterica contamination on grape tomatoes by washing with thyme oil, thymol, and carvacrol as compared with chlorine treatment
01.dec.10
Journal of Food Protection
Lu, Yingjian; Wu, Changqing
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00017
Abstract:
In recent years, multistate outbreaks of Salmonella enterica serovars were traced to tomatoes and resulted in serious economic loss for the tomato industry and decreased consumer confidence in the safety of tomato produce. Purified compounds derived from essential oils such as thymol and carvacrol had wide inhibitory effects against foodborne pathogens including Salmonella. The objective of this study was to determine the antimicrobial activities of thymol, carvacrol, and thyme oil against Salmonella on grape tomatoes. Surface-inoculated grape tomatoes were washed with 4% ethanol, 200 ppm of chlorine, or one of six washing solutions (thymol [0.2 and 0.4 mg/ml], thyme oil [1 and 2 mg/ml], and carvacrol [0.2 and 0.4 mg/ml]) for 5 or 10 min. There was no significant difference in the reduction of S. enterica serovars when different washing times were used (P > 0.05). Thymol (especially at the concentration of 0.4 mg/ml) was the most effective (P < 0.05) among the three natural antimicrobial agents, which achieved >4.1-log reductions of S. enterica serovars Typhimurium, Kentucky, Senftenberg, and Enteritidis on grape tomatoes after a 5-min washing and >4.3-log reductions after a 10-min washing. A >4.6-log reduction in the S. enterica populations in comparison to control was observed with the use of thymol solutions. The uses of these antimicrobial agents achieved significant log reductions of Salmonella on inoculated grape tomatoes and decreased dramatically the risk of potential transmission of pathogens from tomatoes to washing solutions. None of these antimicrobial agents decreased the total phenolic and ascorbic acid content, nor did any of them change the color and pH values or affect the taste, aroma, or visual quality of grape tomatoes. Therefore, 0.4 mg/ml thymol has great potential to be an alternative to chlorine-based washing solution for fresh produce.
Outbreaks where food workers have been implicated in the spread of foodborne disease. Part 11. use of antiseptics and sanitizers in community settings and issues of hand hygiene compliance in health care and food industries
01.dec.10
Journal of Food Protection
Todd, Ewen C.D.; Greig, Judy D.; Michaels, Barry S.; Bartleson, Charles A.; Smith, Debra; Holah, John
http://www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00024
Abstract:
Hand washing with soap is a practice that has long been recognized as a major barrier to the spread of disease in food production, preparation, and service and in health care settings, including hospitals, child care centers, and elder care facilities. Many of these settings present multiple opportunities for spread of pathogens within at-risk populations, and extra vigilance must be applied. Unfortunately, hand hygiene is not always carried out effectively, and both enteric and respiratory diseases are easily spread in these environments. Where water is limited or frequent hand hygiene is required on a daily basis, such as for many patients in hospitals and astronauts in space travel, instant sanitizers or sanitary wipes are thought to be an effective way of preventing contamination and spread of organisms among coworkers and others. Most concerns regarding compliance are associated with the health care field, but the food industry also must be considered. Specific reasons for not washing hands at appropriate times are laziness, time pressure, inadequate facilities and supplies, lack of accountability, and lack of involvement by companies, managers, and workers in supporting proper hand washing. To facilitate improvements in hand hygiene, measurement of compliant and noncompliant actions is necessary before implementing any procedural changes. Training alone is not sufficient for long-lasting improvement. Multiactivity strategies also must include modification of the organization culture to encourage safe hygienic practices, motivation of employees willing to use peer pressure on noncompliant coworkers, a reward and/or penalty system, and an operational design that facilitates regular hand hygiene.
bites is produced by Dr. Douglas Powell and food safety friends at Kansas State University. For further information, please contact dpowell@ksu.edu or check out bites.ksu.edu.
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