Fw: [BITES-L] bites Aug.21/10
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Date: Sat, 21 Aug 2010 10:06:15 -0500
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Subject: [BITES-L] bites Aug.21/10
bites Aug.21/10
US: Growing concern about tainted eggs after recall
US: Salmonella worries: Recalled egg total passes half a billion
US: Cal-Maine adds 800,000 dozen eggs to recall
Always fresh, never frozen: hepatitis A in Wendy's employee
Math lessons for locavores
UK: Restaurant owners fined for food safety offences
Nuevo Folleto Informativo: Lavado de aves es un peligro para la inocuidad alimentaria
Is it legal to eat a cat in the U.S.?
I'm in love with your facial symmetry, but it's the alcohol talking, not me: beer goggles explained
NORTH CAROLINA: Mass rabies exposure from raccoon
US: Public health threat of emerging zoonoses related to intensified food production systems
Outbreak of Q fever in a meat processing plant, Maine-et-Loire, February 2009
A mathematical model of inactivation kinetics for a four-strain composite of Salmonella Enteritidis and Oranienberg in commercial liquid egg yolk
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US: Growing concern about tainted eggs after recall
21.aug.10
New York Times
William Neuman
http://www.nytimes.com/2010/08/21/business/21eggs.html?_r=1&hpw
A national outbreak of salmonella was linked on Friday to another major egg producer, Hillandale Farms, prompting the recall of an additional 170 million eggs in 14 states.
The latest action — the third recall announcement in two weeks for eggs — is bound to shake the confidence of consumers rattled by a succession of food safety scares in recent years, most prominently for foods like beef and lettuce.
The idea that half a billion suspect eggs have been circulating in the food supply comes as an embarrassment for the egg industry and federal regulators. New egg safety rules went into effect in July that the Food and Drug Administration had said would prevent tens of thousands of salmonella illnesses a year.
"You have to treat eggs with the assumption that they're contaminated with salmonella," said Carol Tucker Foreman, a food safety expert of the Consumer Federation of America. "We may all object to the fact that we have to treat food like toxic waste, but if we don't want to get sick, and especially if you have someone in your house that's immune-suppressed, you have to handle things carefully and demand that the standards be set higher."
Hillandale Farms, one of the nation's largest egg companies, said it was recalling eggs produced at two Iowa sites, in some cases as far back as April.
It follows an even larger recall by Wright County Egg, also of Iowa, which recalled 228 million eggs on August 13, and then expanded its recall by an additional 150 million eggs on Wednesday.
Hundreds, perhaps thousands, of cases of salmonella since May have been linked to tainted eggs, according to federal health officials. Investigators are continuing to look at the clusters of illness to see whether any other egg producers might be linked to the outbreak.
Investigators are also looking at ties between the two egg farms operated in Iowa by Hillandale and the five farms run by Wright County Egg, which is owned by the DeCoster family, a major egg producer.
Sherri McGarry, a director at the F.D.A.'s Center for Food Safety and Applied Nutrition, said federal and state officials were working hard "to get contaminated product off the market so consumers are protected and public health is protected."
She said the Hillandale recall was prompted when Minnesota officials traced a cluster of illnesses in that state to the eggs from the company's Iowa plants.
Doug Schultz, a spokesman for the Minnesota health department, said seven people had become ill with salmonella in mid-May after eating chile rellenos at a Mexican restaurant called Mi Rancho in Bemidji, Minn. He said that investigators established a connection to Hillandale eggs on May 24.
It was not clear why the F.D.A. did not act on the information sooner.
US: Salmonella worries: Recalled egg total passes half a billion
21.aug.10
USA Today
Elizabeth Weise
http://www.usatoday.com/yourlife/food/safety/2010-08-20-egg-recall-grows-to-half-a-billion_N.htm?csp=34news&utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+UsatodaycomNation-TopStories+%28News+-+Nation+-+Top+Stories%29
The nationwide effort to pull potentially salmonella-contaminated eggs off the market expanded significantly Friday when a second Iowa egg producer, Hillandale Farms, issued a recall of 170 million of its eggs, according to Associated Press reports. That brings the total amount recalled by two producers to more than half a billion eggs. This makes it "among the largest egg recalls" ever, says Patricia el-Hinnawy, with the Food and Drug Administration.
The eggs recalled by Hillandale Farms of Pennsylvania were sold in 14 states under the brand names Hillandale Farms, Sunny Farms, Sunny Meadow, Wholesome Farms and West Creek.
They were were sold in Arkansas, California, Iowa, Illinois, Indiana, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, Texas and Wisconsin.
US: Cal-Maine adds 800,000 dozen eggs to recall
20.aug.10
Associated Press
http://www.google.com/hostednews/ap/article/ALeqM5hMcetz2VBW_KcovqYIzFzLWhAmOwD9HNG71G0
JACKSON, Miss. -- Cal-Maine Foods Inc., the nation's largest egg seller and distributor, said it is recalling about 800,000 dozen eggs related to an expanded recall tied to a salmonella outbreak.
Cal-Maine said it was notified by an Iowa egg producer that between April 9 and Aug. 19, the producer sold 32 truckloads of eggs, or about 800,000 dozen eggs, to the company. The affected products were added Friday to the expanded nationwide recall related to almost 2,000 illnesses from the strain of salmonella reported between May and July, almost 1,300 more than usual.
Always fresh, never frozen: hepatitis A in Wendy's employee
21.aug.10
barfblog
Doug Powell
http://www.barfblog.com/blog/143756/10/08/21/always-fresh-never-frozen-hepatitis-wendy%E2%80%99s-employee
Toronto Public Health has identified a case of Hepatitis A in an employee at a Wendy's restaurant located at 438 Nugget Avenue in Scarborough. Anyone who consumed food purchased at this restaurant between July 26 and August 6 may have been exposed to the hepatitis A virus. The risk of getting the infection is very low.
Depends on how well the employee washed his or her hands and whether they were prepping salads or other fresh product. Don't eat poop.
http://www.newswire.ca/en/releases/archive/August2010/20/c4191.html
Math lessons for locavores
21.aug.10
barfblog
Doug Powell
http://www.barfblog.com/blog/143763/10/08/21/math-lessons-locavores
Stephen Budiansky, the author of the blog liberalcurmudgeon.com, writes in the N.Y. Times today that the local food movement now threatens to devolve into another one of those self-indulgent — and self-defeating — do-gooder dogmas.
Arbitrary rules, without any real scientific basis, are repeated as gospel by "locavores," celebrity chefs and mainstream environmental organizations. Words like "sustainability" and "food-miles" are thrown around without any clear understanding of the larger picture of energy and land use.
The statistics brandished by local-food advocates to support such doctrinaire assertions are always selective, usually misleading and often bogus. This is particularly the case with respect to the energy costs of transporting food. One popular and oft-repeated statistic is that it takes 36 (sometimes it's 97) calories of fossil fuel energy to bring one calorie of iceberg lettuce from California to the East Coast. That's an apples and oranges (or maybe apples and rocks) comparison to begin with, because you can't eat petroleum or burn iceberg lettuce.
It is also an almost complete misrepresentation of reality, as those numbers reflect the entire energy cost of producing lettuce from seed to dinner table, not just transportation. Studies have shown that whether it's grown in California or Maine, or whether it's organic or conventional, about 5,000 calories of energy go into one pound of lettuce. Given how efficient trains and tractor-trailers are, shipping a head of lettuce across the country actually adds next to nothing to the total energy bill.
It takes about a tablespoon of diesel fuel to move one pound of freight 3,000 miles by rail; that works out to about 100 calories of energy. If it goes by truck, it's about 300 calories, still a negligible amount in the overall picture. (For those checking the calculations at home, these are "large calories," or kilocalories, the units used for food value.) Overall, transportation accounts for about 14 percent of the total energy consumed by the American food system.
The real energy hog, it turns out, is not industrial agriculture at all, but you and me. Home preparation and storage account for 32 percent of all energy use in our food system, the largest component by far.
http://www.nytimes.com/2010/08/20/opinion/20budiansky.html?_r=2
UK: Restaurant owners fined for food safety offences
17.aug.10
Kent News
http://www.kentnews.co.uk/kent-news/Restaurant-owners-fined-for-food-safety-offences--newsinkent38925.aspx
KENT NEWS -- The owners of an oriental restaurant and take away have been fined more than £16,600 for breaking a string of hygiene regulations.
Environmental health inspectors found 15 areas at Kings Hill Palace in West Malling were dirty and greasy with large build ups of food debris including the preparation area, walls and kitchen floor.
The owners, Toto Experience, were also found to be in breach of measures to protect food against contamination.
Food in the chillers was stored uncovered and contained stacked directly on top of each other, dirt was flaking off the walk-in shelves directly above open cooked food and food was being stored in open cans.
More kitchen horrors awaited inspectors as they found raw food stored next to and above cooked food, cooked seaweed in a box that had previously contained raw frozen chicken and a chopping block being used for both raw meat and cooked battered chicken.
Nuevo Folleto Informativo: Lavado de aves es un peligro para la inocuidad alimentaria
16.aug.10
bites
Benjamin Chapman
Traducido por Gonzalo Erdozain
Resumen del folleto informativo mas reciente:
- "Food Standards Agency" (FSA por sus siglas en Ingles), en el Reino Unido, publicó los resultados de un estudio reciente en el cual demostraron que las bacterias de un pollo, al ser lavado, pueden esparcirse hasta a 3 pies del lugar donde se haya lavado dicha ave.
- Limpie y desinfecte utensilios y superficies luego de haber preparado aves crudas.
- Lávese y séquese las manos después de tocar y preparar aves crudas, y luego de lavar los platos.
Los folletos informativos son creados semanalmente y puestos en restaurantes, tiendas y granjas, y son usados para entrenar y educar a través del mundo. Si usted quiere proponer un tema o mandar fotos para los folletos, contacte a Ben Chapman a benjamin_chapman@ncsu.edu.
Puede seguir las historias de los folletos informativos y barfblog en twitter
@benjaminchapman y @barfblog.
Is it legal to eat a cat in the U.S.?
20.aug.10
barfblog
Doug Powell
http://www.barfblog.com/blog/143752/10/08/20/it-legal-eat-cat-us
Depends on the state, according to Brian Palmer of Slate Magazine.
"When police in Western New York pulled over Gary Korkuc for blowing off a stop sign on Sunday, they found a live cat in his trunk, covered in cooking oil, peppers, and salt. Korkuc told authorities that his pet feline was "possessive, greedy, and wasteful" and that he intended to cook and eat it. Korkuc has been charged with animal cruelty. …
"Few states have specific laws barring the use of pets for food. The ones that do typically ban the slaughter or sale of dog and cat meat. The state of New York expressly prohibits "any person to slaughter or butcher domesticated dog (canis familiaris) or domesticated cat (felis catus or domesticus) to create food, meat or meat products for human or animal consumption." It's not clear whether the eating itself is outlawed or only the butchery. If you managed to buy dog or cat flesh from someone else who broke the anti-slaughter law, you might be OK. The law also doesn't cover ferrets, gerbils, parakeets, or other less familiar pet species. (Although the general anti-cruelty law might protect exotics.)
"California's anti-pet-eating law has a broader reach. It bars possession of the carcass, so having bought your cat steaks from someone else wouldn't be a useful alibi. The California law also protects "any animal traditionally or commonly kept as a pet or companion," rather than just Fido and Fluffy. The statute is somewhat untested, though, so no one really knows which animals are included.
Pigs are not, even though they are commonly kept as pets, because they are farm animals. Horses are specifically covered by a different section of the code. There's no precedent on iguanas, goldfish, or boa constrictors. …
"Authorities won't have any trouble prosecuting Korkuc, the Western New Yorker who was marinating his cat in the trunk. Whether or not he really intended to eat his feline, keeping a companion animal in a motor vehicle without proper ventilation is illegal. Rubbing the cat with chili-infused oil, while not specifically addressed, is also a violation of the state's general cruelty law, which prohibits torture."
http://www.slate.com/id/2263794/?from=rss
I'm in love with your facial symmetry, but it's the alcohol talking, not me: beer goggles explained
20.aug.10
barfblog
Doug Powell
http://www.barfblog.com/blog/143753/10/08/20/i%E2%80%99m-love-your-facial-symmetry-it%E2%80%99s-alcohol-talking-not-me-beer-goggles-explaine
The Urban Dictionary defines beer goggles as the "phenomenon in which one's consumption of alcohol makes physically unattractive persons appear beautiful."
A recent study in the journal Alcohol has found a reason why some of us might find people we normally would consider ugly to be handsome: we stop noticing facial symmetry.
In a new study, scientists went to bars near their university in England and asked students to participate in a small experiment. The students were given a breathalyzer test to determine whether or not they were drunk and then asked to determine which photo in a pair, repeated for 20 pairs, was the more attractive and which was the more symmetrical.
Students who were sober found symmetrical faces more attractive and were able to determine more readily which were the more symmetrical faces. But the drunk students lost both their preference for symmetry and their ability to detect it. Women more readily lost this ability than did men.
http://blogs.smithsonianmag.com/science/2010/08/17/the-truth-behind-beer-goggles/
NORTH CAROLINA: Mass rabies exposure from raccoon
21.aug.10
Worms & Germs Blog
Scott Weese
http://www.wormsandgermsblog.com/2010/08/articles/animals/other-animals/mass-rabies-exposure-from-raccoon/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+WormsAndGermsBlog+%28Worms+and+Germs+Blog%29
Yet again, a large number of people are undergoing rabies post-exposure treatment because they were exposed to a rabid raccoon that was 'adopted' from the wild. In this case, a North Carolina family found a baby raccoon at the side of the road and decided to bring it home. Over the next couple weeks, various family and friends handled the raccoon, and many were bitten or scratched in the process. The raccoon then died and was identified as being rabid. 45 people are now being assessed to determine whether they need to be treated.
The family dog, which was unvaccinated, has been taken by Animal Control and now faces either a 6 month strict quarantine or euthanasia. I suspect the dog will be euthanized.
So, this probably well-meaning but misguided action has resulted in:
* the need for costly post-exposure treatment of many people
* presumably a stressful period for many of those people
* probably the death of the pet dog. Not having the dog vaccinated played a big role here too, since if it was vaccinated, it would only face a 45 dog observation period at home, not a strict 6 month quarantine.
Fortunately, the raccoon was tested. Otherwise we might be talking about human deaths from rabies, instead of people needing post-exposure treatment. The people that took in the raccoon could also face charges since keeping wildlife without a permit is illegal, but it sounds like that's unlikely to occur.
A few take-home messages from a situation like this:
* Keep wildlife in the wild.
* Vaccinate your pets.
* If you are exposed to an animal that is acting strangely, make sure it's tested for rabies (they did this right, at least).
US: Public health threat of emerging zoonoses related to intensified food production systems
01.sep.10
CDC, Volume 16, Number 9–September 2010
http://www.cdc.gov/eid/content/16/9/1503.htm
To the Editor: Cutler et al. bring welcome attention to the importance of new and reemerging zoonotic diseases in the industrialized world (1). However, they make no mention of industrialized systems of food animal production, major sources of antimicrobial drug–resistant bacterial pathogens (2) that are among the most globally prevalent and emerging infectious diseases (3). These systems have practices characterized by crowded and unsanitary confinement of animals and routine use of antimicrobial agents in animal feeds (2). For example, in the same issue, Dutil et al. (3) reported on increases in ceftiofur resistance in Salmonella enterica isolates from food, which they associate with use of this drug in broiler poultry production.
Recognition of the role of industrial food animal production in driving vancomycin resistance in enterococci prompted restrictions on agricultural antimicrobial drug use in the European Union; unfortunately, few measures have been implemented in the rest of the world (including the United States) (4). Industrialized food animal production is now assumed to contribute to the emergence of new strains of community-associated methicillin-resistant Staphylococcus aureus with varying potential for infecting humans (5). Because the industrial model of food animal production is rapidly expanding globally (2), this source must be included in surveillance, research, and tracking programs for effective prevention of emerging zoonotic disease.
Ellen SilbergeldComments to Author, Meghan Davis, Bath Feingold, Alan Goldberg, Jay Graham, Jessica Leibler, Amy Peterson, and Lance B. Price
Author affiliations: Johns Hopkins School of Public Health, Baltimore, Maryland, USA (E. Silbergeld, M. Davis, B. Feingold, A. Goldberg, J. Leibler, A. Peterson); American Association for the Advancement of Science, Washington, DC, USA (J. Graham); and Center for Metagenomics and Human Health Translational Genomics Research Institute, Flagstaff, Arizona, USA (L.B. Price)
Suggested citation for this article:
Silbergeld E, Davis M, Feingold B, Goldberg A, Graham J, Leibler J, et al. New infectious diseases and industrial food animal production [letter]. Emerg Infect Dis [serial on the Internet]. 2010 Sep [date cited]. http://www.cdc.gov/EID/content/16/9/1503.htm
DOI: 10.3201/eid1609.100144
References
1. Cutler SJ, Fooks AR, van der Poel WHM. Public health threat of new, reemerging, and neglected zoonoses in the industrialized world. Emerg Infect Dis. 2010;16:1–7. Medline DOI: 10.3201/eid1601.081467
2. Silbergeld EK, Graham J, Price L. Industrial food animal production, antimicrobial resistance, and human health. Annu Rev Public Health. 2008;29:151–69. Medline DOI: 10.1146/annurev.publhealth.29.020907.090904
3. Dutil L, Irwin R, Finley R, Ng LK, Avery B, Boerlin P, et al. Ceftiofur resistance in Salmonella enterica serovar Heidelberg from chicken meat and humans, Canada. Emerg Infect Dis. 2010;16:48–54. Medline DOI: 10.3201/eid1601.090729
4. Nunnery J, Angulo FJ, Tollefson L Public health and policy. Prev Vet Med. 2006;73:191–5. Medline DOI: 10.1016/j.prevetmed.2005.09.014
5. Cuny C, Friedrich A, Kozytska S, Laver F, Nübel U, Ohlsen K, et al. Emergence of methicillin-resistant Staphylococcus aureus (MRSA) in different animal species. Int J Med Microbiol. 2010;300:109–17. Medline DOI: 10.1016/j.ijmm.2009.11.002
In Response: Silbergeld et al. highlight pertinent points about how stochastic events can lead organisms to acquire adaptive advantages through lateral gene transfer ( 1). Word constraints of our earlier article precluded detailed debate of many such topics, and we welcome the opportunity to discuss this further. The role of industrial food animal production in driving the development of antimicrobial drug–resistant pathogens is indeed a topic of great concern.
Commonly, reemergence of infections is caused by changes in the environment or the host, genetic changes of pathogens, or alteration in the dynamic interactions that unite them. Our need for intensive protein production can have explosive consequences, as seen with the recent outbreak of Q fever among humans residing near goat farming areas in the Netherlands (2) and the emergence of antimicrobial drug–resistant organism variants with selective advantages, such as methicillin-resistant Staphylococcus aureus (3). The bombardment of livestock with antimicrobial drugs for therapy and prophylaxis and as growth-enhancing agents (in Europe before 2006) has provided selective pressure for acquisition of resistance, which occurs globally (4). Even exposure to various biocides has been linked with acquisition of resistance to therapeutic antimicrobial agents (5), although such resistance has not yet been demonstrated in natural populations. Risk prevention within and management of intensified food production systems is a continuing challenge. Similarly problematic are pathogens that increase in general, such as RNA viruses that under the recent selective pressure have rapidly acquired resistance to oseltamivir (6). A common feature of all these facts is that such traits and clones of increased fitness can disseminate rapidly around the globe. For these reasons, we need robust surveillance mechanisms; ability to predict spread; cohesive intervention strategies; and lastly, but by no means least, strong collaborative links between previously segregated human and veterinary fields that extend to producers and policy makers.
Sally J. Cutler, Anthony R. Fooks, and Wim H.M. van der PoelComments to Author
Author affiliations: University of East London, London, UK (S.J. Cutler); University of Liverpool, Liverpool, UK (A.R. Fooks); Veterinary Laboratories Agency, Weybridge, UK (A.R. Fooks); and Central Veterinary Institute, Lelystad, the Netherlands (W.H.M. van der Poel)
Suggested citation for this article:
Cutler SJ, Fooks AR, van der Poel WHM. Public health threat of emerging zoonoses related to intensified food production systems [letter]. Emerg Infect Dis [serial on the Internet]. 2010 Sep [date cited]. http://www.cdc.gov/EID/content/16/9/1503.htm
References
1. Silbergeld E, David M, Feingold B, Goldberg A, Graham J, Leibler J, et al. New infectious diseases and industrial food animal production. Emerg Infect Dis. 2010;16:1503.
2. Karagiannis I, Schimmer B, Van Lier A, Timen A, Schneeberger P, Van Rotterdam B, et al. Investigation of a Q fever outbreak in a rural area of the Netherlands. Epidemiol Infect. 2009;137:1283–94. DOI: 10.1017/S0950268808001908
3. van Loo I, Huijsdens X, Tiemersma E, de Neeling A, van de Sande-Bruinsma N, Beaujean D, et al. Emergence of methicillin-resistant Staphylococcus aureus of animal origin in humans. Emerg Infect Dis. 2007;13:1834–9.
4. Hawkey PM, Jones A. The changing epidemiology of resistance. J Antimicrob Chemother. 2009;64(Suppl 1):i3–10. DOI: 10.1093/jac/dkp256
5. Maseda H, Hashida Y, Konaka R, Shirai A, Kourai H. Mutational upregulation of a resistance-nodulation-cell division–type multidrug efflux pump, SdeAB, upon exposure to a biocide, cetylpyridinium chloride, and antibiotic resistance in Serratia marcescens. Antimicrob Agents Chemother. 2009;53:5230–5. DOI: 10.1128/AAC.00631-09
6. Sy CL, Lee SS, Liu MT, Tsai HC, Chen YS. Rapid emergence of oseltamivir resistance. Emerg Infect Dis. 2010;16:723–5.
Outbreak of Q fever in a meat processing plant, Maine-et-Loire, February 2009
20.aug.10
Institut de veille sanitaire
http://www.invs.sante.fr/display/?doc=publications/2010/fievre_q_maine_loire/index.html
The epidemiology unit of the Pays de la Loire has investigated an outbreak of Q fever which occurred in Maine-et-Loire in early 2009 in an establishment employing 1,000 workers and which included a cattleslaughterhouse and a meat processing plant. The investigation focused on actively searching for cases in the plant for the months January to March 2009 and potential sources of contamination and modes of transmission. During the epidemic period in February 2009, 50 cases were confirmed through the presence of IgM specific to Coxiella burnetii. The epidemic curve showed a log-normal appearance, which indicates a one-time exposure or very limited in time. The probable period of contamination was in the second half of January.The attack rate of confirmed cases among the employees of the company was 5.4%. The attack rates were highest in the meat processing workshops (8-10%) and preparation of packages workshops (41%). No cases were observed in the slaughterhouse. Several potential sources of contamination were examined. Exposures to the foetus or placenta, known to have very high bacterial burden when infected were explored in priority. The rupture of a calf foetal blood bag in a transport vehicle parked in the clean courtyard of the factory on January 29, 2009 was considered the most likely source. The broadcast mode, typically by aerosol, is poorly understood, the mist generated by pressure washing soil or potentially contaminated material, could explain the distribution of cases in workshops a priori not at high risk of Q fever.
A mathematical model of inactivation kinetics for a four-strain composite of Salmonella Enteritidis and Oranienberg in commercial liquid egg yolk
20.aug.10
Food Microbiology
Johari S. Jordan, Joshua B. Gurtler, Harry M. Marks, Deana R. Jones and William K. Shaw Jr.
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6WFP-50TRX5B-1&_user=10&_coverDate=08%2F20%2F2010&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=56774c6371ccad8fa198a6a4f6da2ea3
Abstract
The goal of this study was to develop a general model of inactivation of salmonellae in commercial liquid egg yolk for temperatures ranging from 58 °C to 66 °C by studying the inactivation kinetics of Salmonella in liquid egg yolk. Heat-resistant salmonellae (three serovars of Enteritidis [two of phage type 8 and one PT 13] and one Oranienburg) were grown to stationary phase in Tryptic Soy Broth and concentrated ten-fold by centrifugation. Each inoculum was added to liquid egg yolk and mixed thoroughly, resulting in a final population of ca. 7 log CFU/ml egg yolk. Inoculated yolk was injected into sterile glass capillary tubes, flame-sealed and heated in a water bath at 58, 60, 62, 64, and 66 °C. Capillary tubes were ethanol sanitized, rinsed, and contents were extracted. Yolk was diluted, surface plated onto Tryptic Soy Agar + 0.1% sodium pyruvate and 50 ug/ml nalidixic acid and incubated at 37 °C for 24 h before colonies were enumerated. Decimal reduction values were calculated from survivor curves with a minimum inactivation of 6 log CFU/ml at each temperature. Survival curves (except for 66 °C) featured initial lag periods before first order linear inactivation. Estimated asymptotic D‑values were 1.83 min at 58 °C, 0.69 min at 60 °C, 0.26 min at 62 °C, 0.096 min at 64 °C and 0.036 min at 66 °C. The estimate of the z-value was ca. 4.7 °C with standard error of 0.07 °C. A linear relationship between the log10 of the lag times and temperature was observed. A general kinetic model of inactivation was developed. The results of the study provide information that can be used by processors to aid in producing safe pasteurized egg yolk products and for satisfying pasteurization performance standards and developing industry guidance.
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