Scientists in India figure out how Salmonella infect plants

Sunderarajan Padmanabhan of Biotech Times writes that E. coli and Salmonella bacteria are the most common causes of food poisoning. Although most Salmonella outbreaks are linked to contamination during handling and transportation of the vegetables, there are also cases where the infectious bacterium had entered the plant when it was still in the farmland.

A new study by researchers at the Indian Institute of Science (IISc) and the University of Agricultural Sciences (UAS), Bengaluru, has solved the mystery.

They have found that unlike other disease-causing bacteria that enter the root, fruit or leaf by producing enzymes to break down the plant’s cell wall, Salmonella sneaks in through a tiny gap created when a lateral root branches out from the plant’s primary root.

The researchers were studying how different types of bacteria colonize the roots of tomato plants. While other bacteria were spread across the root, Salmonella clustered almost exclusively around areas where lateral roots emerge. When a lateral root pierces open the wall of the primary root to spread across the soil, it leaves behind a tiny opening. They figured out that it was entering through the gap with the help of fluorescent tagging and imaging.

They also noticed that under same conditions a plant with a greater number of lateral roots harbored a greater concentration of Salmonella than one with fewer lateral roots. Similarly, when plants were artificially induced to produce more lateral roots, Salmonella concentration increased.

Tomatoes plucked from these plants also tested positive for Salmonella infection, revealing its ability to travel all the way up to the fruit. “It is just like a systemic infection in humans,” said senior author Dipshikha Chakravortty, Professor, Department of Microbiology and Cell Biology, IISc. The researchers have published a paper on their work in the journal, BMC Plant Biology.

Kapudeep Karmakar, Ph.D. student in the Department of Microbiology and Cell Biology, IISc, and first author of the paper, noted that there are several possible sources from where Salmonella can reach the soil, such as manure containing animal faeces or contaminated irrigation water.

“Various studies show that irrigation water gets contaminated by sewage water. When that irrigation water is applied in the field, the soil becomes the portal for Salmonella to enter,” he said.

Food fraud: Canadian greenhouse edition

Ann Hui of the Globe and Mail reports that a few years ago, federal food inspectors were walking around the warehouses of the Ontario Food Terminal in Toronto – the nerve centre where much of the province’s fresh produce is bought, re-packaged and sold – when they noticed something unusual.

emersonIn the “farmer’s market” area, where only Ontario-grown produce is meant to be sold, the inspectors saw large cartons of greenhouse peppers with conflicting labels. The outside of the boxes had “Product of Canada” stickers, next to visible signs of damage on the cardboard – bits of paper and glue, as if another sticker had been peeled off. And stickers on the inside of the box read “Product of Mexico.”

That discovery in January, 2012, led the Canadian Food Inspection Agency into a three-year investigation of the company behind the peppers, Mucci Farms – the largest such probe in the agency’s history.

After executing three search warrants at the company’s headquarters in Kingsville, Ont., and poring over its computer records and internal e-mails, CFIA investigators pieced together evidence that, between late 2011 and early 2013, Mucci had been selling imported products as Canadian – putting hundreds of shipments of mislabelled produce worth more than $1.4-million onto Ontario grocery store shelves.

In one e-mail described in a court document and obtained by The Globe and Mail, one of the company’s directors, Danny Mucci, responded to a message from an employee about a shortage of Canadian mini cucumbers by telling the worker: “you know what to do to fill…it’s only 30 cases.”

Mucci International Marketing Inc., Mucci Pac Ltd. and two of its directors (Mr. Mucci and Joseph Spano) pleaded guilty in June of this year to eight regulatory offences – including one count against the company for selling food in a “false, misleading or deceptive” manner – and were fined $1.5-million.

Mucci’s lawyer, Patrick Ducharme, said in an interview that the mislabelling was not intentional, and that, given the volume of Mucci’s 1,200-employee operation, the transactions made up “a very small part of what they do.” He also emphasized that they pleaded guilty to regulatory offences, not criminal ones. Criminal charges against Mucci International and Mucci Pac and the two directors of defrauding the public, and defrauding Costco, Loblaw and Sobeys – to whom Mucci sold the produce – were withdrawn.

The case sent shockwaves through the country’s agriculture industry, and the Ontario Greenhouse Vegetable Growers called it a “unique” precedent. “My hope is that it’s an isolated case,” the marketing board’s manager, Rick Seguin, said in an interview.

If the best you can do is hope, then OGVG is in for trouble.

I helped – or did – set up the OGVG on-farm food safety program way back when OFFS wasn’t cool – about 1998.

We got a couple of papers out of it, along with reams of anectodes and observations and every time I’ve blogged about them, the new types at OGVG have threatened to sue (that’s a pic, upper left, of my 14-monty-old grandon #2, Emerson, instead of tomatoes; sue that).

I’m used to that.

And since I’m just a lowly former academic, the legal types tell me, you can’t afford it.

So I’ll let CFIA and the Globe run with it.

powell_greenhouseI had nothing to do with it.

Can only sit back and sigh.

For years, experts have been sounding the alarm on mislabelling and food fraud. Increasingly, they say, criminal organizations around the world are targeting the food system, intercepting supply chains and deliberately misrepresenting or adulterating products – and costing the food industry between $10-billion and $15-billion (U.S.) each year, according to the U.S.-based Grocery Manufacturers Association.

And, according to conversations with experts in the Canadian food industry, scientists and regulators, the problem is widespread within our own borders.

But even the CFIA does not seem to know just how widespread it is. Individual cases provide an incomplete picture. And the 74 cases of non-compliance with labelling laws from the past year published on the CFIA website – a number the agency say has held steady over the past five years – present only a portion of incidents where the agency has found companies breaking the rules. It includes only the cases in which the products were actually seized and detained or disposed of, but also includes technical infractions, like language or font size on packaging.

When asked how prevalent the problem is in Canada, the agency cited U.S. data that show fraud affects about 10 per cent of all food products globally. It also acknowledged it has not yet conducted a widespread survey of its own to understand its full impact within Canada.

In his years as a lawyer representing companies in intellectual property and anti-counterfeiting cases in Canada, Lorne Lipkus has seen cases of food fraud ranging from counterfeit basmati rice (knockoffs of a high-end brand) to fake ginseng.

“You’d think: ‘How expensive is it to grow a bag of rice,’” he said. “But if someone’s making something and making a profit out of it, somebody’s counterfeiting it. … Everything we do in Canada is reactive. We have very poor laws, compared to other countries. And we haven’t had any government involved in the longest time – I’m talking decades – willing to provide the resources to law enforcement to do anything about counterfeiting.”

In EU countries, border officials have the authority to seize and destroy goods they believe are counterfeit. In Canada, customs officials can detain a product, but it is then incumbent on the complainant to undertake court action and to pay for the goods to remain in detention until the case is heard – which can cost in the tens of thousands of dollars.

Most alarming, he said, is that the scope of the problem is not understood because no agency is specifically looking for fraud.

On the issue of mislabelling, experts also point to policy initiatives abroad – such as a U.S. proposal to require companies to have food fraud prevention programs – as evidence others seem to take the issue more seriously.

Although the CFIA has not conducted a full survey of the issue in Canada, James Crawford, acting associate vice-president of operations with the federal agency, said CFIA receives about 40 complaints a year about possible food misrepresentation.

In an interview, Mr. Crawford said the agency takes food fraud seriously. He also said Canadians are generally safe from adulterated food – pointing to a Conference Board of Canada study in 2014 that ranked the country’s food system as the safest of 17 OECD countries surveyed.


That was a bullshit survey with criteria based on nothing.

On fraud, he said, “we’re proactive and reactive.”

He said CFIA staff conduct regular inspections of imported and domestic food – including daily inspections at meat processing plants. Still, he was not able to say what percentage of products undergoes such scrutiny for labelling.

“We can’t inspect every … import or domestically produced food in Canada. It’s impossible. That’s why we have a risk-based plan. And it allows us to focus on where we think the high risks are.” Some of the things the agency takes into account in prioritizing inspections include food type and likelihood for illness, and each company’s track record of compliance.

Even countries with the most aggressive approaches faced the reality that food fraud is not easily confined by borders.

In Canada, much of the action on the issue has been industry-led. Large retailers in Canada like Loblaw or Costco have programs to safeguard against adulterations, requiring suppliers to subscribe to standardized food safety programs, and undergo annual audits.


Audits and inspections are largely shit.

As for Mucci, it is on a three-year probation during which CFIA inspectors will have free access to its premises and computer records. Mr. Ducharme says the company is doing everything it can to ensure accuracy of its labelling, including appointing a compliance officer and reviewing all of its processes.

He believes the CFIA targeted Mucci in part to set an example. “I don’t think it’s insignificant that the place that was targeted for the big investigation was the biggest in the industry,” he said. “They know Mucci’s the biggest. The best.”


Denton Hoffman: Champion of on-farm food safety

My longtime friend and mentor, Denton Hoffman, has fallen on hard times.


He slipped on some icy stairs in Guelph, had brain swelling and a subsequent stroke (that’s Denton on the right, with my asparagus baron grandfather, about 15 years ago).

At the suggestion of Gord Surgeoner, I met with Denton as a newly minted prof back in 1998 to devise an on-farm food safety program for the Ontario Greenhouse Vegetable Growers. At least three of my grad students went through the drill, and there was this time, we thought we’d killed Chapman.

Ben and I went along with Uncle Denton to the Canadian Horticulture Council meeting in Montreal in Feb. 2003. I had chaired a national committee on on-farm food safety program implementation – and the advice was completely ignored – Chapman and I had done years of groundwork with Denton and the Ontario Greenhouse Vegetable Growers, and we agreed to share a room at the annual meeting to cut down on expenses.

There was a couple of receptions and I still remember Ben and I asking Uncle Denton for drink tickets. We then retired to a hotel lounge and I knew trouble was ahead when Chapman asked for a cigarette.

He then went to the bathroom.

He didn’t return.

He showed up a few hours later, seemingly intact.

In 2009, Denton wrote:

As you journey through life you meet the occasional person who makes a real difference.  Dr. Douglas Powell is one of those – to say the least.

Doug called me recently to talk about the early years.  He was new in the On Farm Food Safety business when I was working with the Ontario Greenhouse vegetable group.  Doug was at the University of Guelph and I would talk to him about the phone call I didn’t want to get.  This would be the imaginary call from a senior’s residence wondering why all the occupants were very sick after consuming a fresh salad, and if the cause may have been the greenhouse tomatoes. I never got that call—thank God–but I wanted to be ready.  And that readiness included a strong response indicating we had an On Farm Food Safety program and proof we were capable of tracing our greenhouse product. We’ve seen several incidences in the past few years with certain fresh veggies and berries that almost ruined the industry and certainly crippled those markets for a year or so.

From the University of Guelph and the beginning of the On Farm Food Safety program, Doug has moved to Kansas State University where he is associate professor of food safety. He is still very much in the industry – just relocated to a different university — and still writing newsletters, hence the reputation of “the guru” of On Farm Food Safety.

Doug has remained a good friend over all these years. We developed a bond as we developed an On Farm Food Safety program for greenhouse vegetables and more.  Doug’s philosophy was to keep it simple.  He could relate to growers, and had an uncanny ability to make the complicated science of bacterial contamination simple and understandable. Early on, he received a little help from Dr. Gord Surgeoner.  These were the seeds of the On Farm Food Safety program in Canada, spreading from Ontario Greenhouse to CHC and to most vegetable growers across Canada.

I can still see Doug in an old T-shirt and jeans, holes in both, and running shoes–that was his fashion statement. Of course, his description of toilet paper “slippage” resulting in fecal contamination on your finger was priceless, but his crude description helped to break down the mystery of bacterial contamination by food handlers with dirty hands. Seems to me I got a T-shirt from Doug with “Don’t Eat Poop” written on the front.  Doug continues to be a great communicator, a fair goalie, poor at politics but great at On Farm Food Safety and raising little girls.

Thanks, Doug.  I am proud to say I knew you back when.

And as Ben said yesterday, Denton was a great mentor on how to deal with crazy industry folks.

Denton’s brain still works, and he can be contacted at: 222 Mountainview Road North suite 217

Georgetown,On L7G 3R2

phone: 905-877-1828×1217


This guy was a champion of on-farm food safety, long before it was fashionable.

Six cases of botulism in Azerbaijan in January; linked to home pickled tomatoes

Last fall a neighbor told me about a how he was making kimchi, a fermented cabbage, carrot and onion concoction, in his kitchen. He wanted to pickle vegetables for health reasons and remembered what his grandmother had done.

His steps were fairly rudimentary, and a recipe for botulism: he put some vegetables into a mason jar, added some water, put the lid on it and tightened it as hard as it could go. Then he left it on the counter for a week.pickled-tomatoes_1472572c

According to AzerNews, home canned food has been linked to a death a handful of illnesses.

We are accustomed to hear about food poisoning in summertime and may neglect winter’s main danger – botulism -which may strike us down.

In the first month of this year, 64 cases of food poisoning were registered in Azerbaijan. The total number of victims of these poisoning cases reaches 92 people, said Imran Abdullayev, Head of Hygiene and Epidemiology Center Department of the Health Ministry.

Moreover, six cases of botulism were registered last month, which harmed nine people leaving one dead. The poisoning was due to homemade pickled tomatoes.

Everyone and especially those who love homemade pickles should remember storage precautions in winter.

The Centre of Hygiene and Epidemiology urges people to follow hygiene rules at home and buy food from reliable catering outlets and grocery stores to avoid food poisoning. Special attention should be paid to children’s’ nutrition.

To avoid food poisoning, one must simply follow hygiene rules at home and buy food in reliable catering outlets and grocery stores.

Prevention of botulism is simple: combining a refrigeration temperature with salt content and acidic conditions. This combination stops the growth of the bacteria and toxin.

Commercial canned goods are made by food business that require recipes to be evaluated for safety and receive inspections from food safety folks. Ingredients, acidity and canning processing procedures can all impact the safety of the final product.

Home canned are amongst the riskiest foods for botulism. In addition to botulism, acid tolerant pathogens such as E. coli O157 can persist in canned foods and lead to illnesses if the products aren’t processed correctly. The good folks at the National Center for Home Food Preservation has a massive database of recipes and processing times at

Food Safety Talk 68: We Found It In Wild Pig Feces

Food Safety Talk, a bi-weekly podcast for food safety nerds, by food safety nerds. The podcast is hosted by Ben Chapman and barfblog contributor Don Schaffner, Extension Specialist in Food Science and Professor at Rutgers University. Every two weeks or so, Ben and Don get together virtually and talk for about an hour.  They talk about what’s on their minds or in the news regarding food safety, and popular culture. They strive to be relevant, funny and informative — sometimes they succeed. You can download the audio recordings right from the website, or subscribe using iTunes.keith-richards-pic-wireimage-184790458

In Episode 68, Don bravely participated without a microphone boom.  Ben feels good despite his messy office.

Ben mentions that he is currently obsessed with the Rolling Stones and likes the Shine a Light Film, Jumpin’ Jack Flash, (the song not so much the Whoopi Goldberg spy comedy film), and the song Salt of the Earth from the Stones album Beggars Banquet.  They then discuss movies every kid needs to see before they turn thirteen such as Indiana JonesGhostbustersE.T., and Diary of a Wimpy Kid and classic kids books including The Hardy BoysEncyclopedia BrownThree InvestigatorsKey to the Treasure, and A Wrinkle in Time.

The guys then discuss their recovery after IAFP, as a follow-up to FST 66. As president of IAFP Don was very busy at the conference with meetings, breakfasts, committee responsibilities, and other assorted duties.  He made the conference manageable by shirking his student poster responsibilities, not going to any talks, and skipping PDG meetings. He did however give a talk on based on a paper he has been working on with his CDC and EHS-Net (pronounced S-net) colleagues.

The guys then drift to other podcasts, especially Alton Brown’s series and in particular one he did with William Shatner.  If you like podcasts, food, Alton Brown, or William Shatner, this stupendous podcast is highly recommended for you.

Thirty-five minutes in they decide that they should talk about food safety and get to Outbreak Flashback about a 2008 Salmonella Saintpaul outbreak that affected over 1400 nationally (as per Michelle Danyluk‘s suggestion. Initial CDC epidemiology analysis indicated the illnesses were associated with eating tomato dishes and FDA issued a health advisory on tomatoes.  This NEJM article shows the case control studies that layout why the CDC initially thought the source was tomatoes. After tomatoes were removed from the market the illness continued and with additional data available the CDC later concluded that jalapeño and Serrano peppers were the likely source.  Epidemiologic analysis was confounded by the fact that many illnesses were from restaurants where peppers were in dishes that contained multiple ingredients.  Additionally the production and supply chain was very complex as is shown in the FDA’s traceback diagram. A key aspect of this outbreak is that it significantly harmed reputation and sales of the tomato industry, which estimates $400 million lost dollars as a result of the FDA’s erroneous health advisory. Talk turned to growers seeking indemnification or financial compensation for situations when the government agencies are incorrect about outbreaks.

  The guys then discuss a voluntary recall by Wawona Packing Co. on fresh peaches and stone fruit.  A receiving company in Australia detected the presence of Listeria monocytogenes.  This later led to a recall of baked goods in Wegman’s supermarket chain presumably because Wegman’s baking process is not validated. There are a surprisingly high number of comments posted to the Wegman’s article in Food Safety News which caused the guys to consider if the public health implications of this recall are more significant than first thought.  For Listeria monocytogenes (LM) there are not a lot of outbreaks but rather sporadic cases; CDC estimates in 2013 there were 0.26 LM illness cases per 100,000 people in the US (for every case reported there are 2 cases not diagnosed).  The guys then discuss food safety gaps common in fresh produce including poorly executed washing processes and traceability deficiencies.

 In after dark the guys discuss that Dean Richard Linton, Dean of the NCSU College of Ag, has selected the 2014 Dean’s ice cream which is dark chocolate, tart cherries, chocolate chunks and marshmallow swirl.

EFSA: Scientific Opinion on the risk posed by Salmonella and Norovirus in tomatoes

Tomatoes may be minimally processed to obtain ready-to-eat products, and these steps include selection, washing, cleaning, stem removal, cutting, packaging and storage.

tomatoEpidemiological data from the EU have identified one salmonellosis outbreak and one Norovirus outbreak associated with tomato consumption between 2007 and 2012. Risk factors for tomato contamination by Salmonella and Norovirus were considered in the context of the whole food chain.

Available estimates of the Salmonella and Norovirus occurrence in tomatoes were evaluated together with mitigation options relating to prevention of contamination and the relevance of microbiological criteria. It was concluded that each farm environment represents a unique combination of risk factors that can influence occurrence and persistence of pathogens in tomato production.

Appropriate implementation of food safety management systems including Good Agricultural Practices (GAP), Good Hygiene Practices (GHP) and Good Manufacturing Practices (GMP), should be primary objectives of tomato producers. The current lack of data does not allow the proposal of a Hygiene Criterion for E. coli at primary production of tomatoes and it is also not possible to assess the suitability of an EU-wide E. coli Process Hygiene Criterion.

There are Food Safety Criteria for the absence of Salmonella in 25 g samples of ready-to-eat pre-cut tomatoes as well as in unpasteurised tomato juice placed on the market during their shelf life. A Food Safety Criterion for Salmonella in whole tomatoes could be considered as a tool to communicate to producers and processors that Salmonella should not be present in the product.

Testing of tomatoes for Salmonella could be limited to instances where other factors indicate breaches in GAP, GHP, GMP or HACCP programmes. It is currently not possible to provide a risk base for establishing a Norovirus Food Safety Criterion for these foods.

The consequences of unsafe home canning are scary

With the first ramps making their way to New York restaurants, the North Carolina spring is here.

As the top two-thirds of North America thaws out, the bottom third is gearing up for the home canning season. If done incorrectly (without acid or pressure as a control step) things can get scary.canned-tomatoes

According to ASIA-plus, 33 residents of a Tajikistan village have contracted botulism from a risky batch of home canned tomatoes, tragically leading to a 10-year-old’s death.

The boy was one of 33 residents of the Qahramon village in Sughd’s Asht district who have contracted botulism poisoning by eating home-canned tomatoes. According to the Sughd Center for Sanitary and Epidemiological Supervision, four of them were in the intensive care unit.

“On March 21, some 95 residents of the village of Qahramon gathered to celebrate the Navrouz holiday and 33 of them contracted botulism poisoning by eating home-canned tomatoes,” said the source.  “On March 23, they were taken to the Asht central district hospital, where they were vaccinated (I think they mean treated with antitoxin -ben) against botulism.”
It’s unclear from the report whether the product was just straight tomatoes or had other low acid foods (like peppers or onions added). Modern varieties of tomatoes are lower acid than some of their predecessors – making them a borderline low-acid food. Canned tomatoes require some added acid (lemon juice or vinegar are most common) to keep the Clostridium botulinum spores from germination, outgrowth which can then lead to bot toxin formation.

Hepatitis A again in sun-dried tomatoes ‘celebrity chefs’ favorite’

Hepatitis A has once again popped up in dried tomatoes, but it’s not new.

The Daily Mail reports U.K. health types are investigating an outbreak of hepatitis A in at least seven people, linked to sun-dried tomatoes; four were hospitalized.

The health alert was triggered when two of the cases were reported late last year to the Heath Protection Agency.

Wait, Eurosurveillance reported on Feb. 9, 2012, that in October 2011, two primary cases of hepatitis A virus (HAV) infection with identical HAV genotype IB strains to those seen in other outbreaks associated with semi-dried tomatoes were reported in England. Both cases had consumed semi-dried tomatoes.

Epidemiological investigations revealed two additional cases of genotype IB strains with different sequences who also reported having consumed semi-dried tomatoes. In November, five cases of HAV infection with closely related strains were identified in the Netherlands. A foodborne multiple-strain outbreak was suspected.

A spokesman for the Food Standards Agency said, "Sun-dried tomatoes are being investigated as one possible source of the hepatitis A cases. However, no food source has been conclusively identified and no other relevant cases have been reported in the UK.”

Hepatitis A is one of the few causes of foodborne illness that only cycles through humans – and their poop. An outbreak of hepatitis A means human sewage came into contact with the food (which then wasn’t cooked) or someone shedding the virus had a poop, failed to adequately wash their hands, and then prepared an uncooked food.

Some 140 people became sick with hepatitis A in Australia in late 2009 linked to semi-dried tomatoes.

Une mauvaise température de conservation, facteur-clé de l’intoxication alimentaire à Salmonella en 2008

Translated by Albert Amgar

Des piments ont été la cause première de l’intoxication alimentaire à Salmonella en 2008 avec plus de 1 500 personnes malades

Des salades de piments et de tomates, qui sont restées à température ambiante, ont pu rendre l’intoxication alimentaire plus importante

Après enquête sur l’intoxication alimentaire à Salmonella en 2008 qui a rendu malades plus de 1500 personnes en Amérique du Nord, le CDC a déterminé que les piments serrano ont été la source primaire de l’intoxication alimentaire. La souche de Salmonella correspondant à la souche épidémique a été retrouvée dans des échantillons d’eau prélevés à la ferme où les piments ont été cultivés. Les enquêteurs pensent que la salsa de tomate, qui contenait aussi les piments, a été conservée au-dessus de 5°C pendant plus de 4 heures et a ainsi augmenté le risque que des personnes soient malades. Les tomates en dés, en tranches ou en purée peuvent fournir un excellent environnement pour des bactéries comme Salmonella de se multiplier. Il s’agit d’une pratique usuelle mais il est risqué de maintenir la salade salsa et le guacamole à température ambiante pendant plus de 4 heures.

Un stockage adapté des produits à base de tomates peut réduire les risques.

Que vous pouvez faire :
– Réfrigérer les salades de tomates en dessous de 5°C.
– Éviter la contamination croisée entre aliments potentiellement contaminés et des salades de tomates servies à température ambiante
– Demander aux fournisseurs de respecter les bonnes pratiques agricoles.
Pour plus d’information contactez Ben Chapman, ou Doug Powell,


Abuso de temperature fue uno de los factores causantes del brote de Salmonella del 2008

Traducido por Gonzalo Erdozain

Resumen del folleto informativo mas reciente:

– El brote de Salmonella que enfermó a 1,500 personas en el 2008 fue causado por pimientos
– Platos con tomates y pimientos dejados a temperatura ambiente pueden haber empeorado el brote
– Refrigere platos con tomates a temperaturas iguales o menores a 41°F

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
Puede seguir las historias de los folletos informativos y barfblog en twitter
@benjaminchapman y @barfblog.