Lettuce rinse with cheese whey can reduce pathogens

Cheese whey fermented by an industrial starter consortium of lactic acid bacteria was evaluated for its antibacterial capacity to control a selection of pathogenic bacteria. For their relevance on outbreak reports related to vegetable consumption, this selection included Listeria monocytogenes, serotype 4b, Escherichia coli O157:H7, and Salmonella Goldcoast.

cheese.wheyOrganically grown lettuce was inoculated with an inoculum level of ∼107 colony-forming unit (CFU)/mL and was left for about 1 h in a safety cabinet before washing with a perceptual solution of 75:25 (v/v) fermented whey in water, for 1 and 10 min. Cells of pathogens recovered were then counted and their number compared with that obtained for a similar treatment, but using a chlorine solution at 110 ppm.

Results show that both treatments, either with chlorine or fermented whey, were able to significantly reduce (p < 0.05) the number of bacteria, in a range of 1.15–2.00 and 1.59–2.34 CFU/g, respectively, regarding the bacteria tested. Results suggest that the use of fermented whey may be as effective as the solution of chlorine used in industrial processes in reducing the pathogens under study (best efficacy shown for Salmonella), with the advantage of avoiding health risks arising from the formation of carcinogenic toxic chlorine derivates.

Preliminary study on the effect of fermented cheese whey on Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella Goldcoast populations inoculated onto fresh organic lettuce

Maria I.S. Santos,1,2,3,4 Ana I. Lima,4 Sara A.V.S. Monteiro,4 Ricardo M.S.B. Ferreira,4 Laurentina Pedroso,3 Isabel Sousa,2 and Maria A.S.S. Ferreira1

1Microbiology Laboratory, Department of Natural Resources, Environment and Territory, DRAT, LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal.

2Eco-Processing of Food and Feed, CEE, LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal.

3Faculty of Veterinary Medicine, Universidade Lusofona de Humanidades e Tecnologias, Lisbon, Portugal.

4Disease & Stress Biology, DRAT, LEAF, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal.

Foodborne Pathogens and Disease, doi:10.1089/fpd.2015.2079

http://online.liebertpub.com/doi/abs/10.1089/fpd.2015.2079

Maybe? USDA says antimicrobial wash reduces health risks in fresh produce

An Agricultural Research Service (ARS) scientist in Wyndmoor, Pennsylvania, and his collaborators have developed an antimicrobial wash that reduces the risk of foodborne pathogens contaminating fresh produce.

usda.produce.washJoshua Gurtler and scientists at NatureSeal Inc. have found that a combination of lactic acid, fruit acids, and hydrogen peroxide can be used in a produce rinse for commercial food distributors. NatureSeal, based in Westport, Connecticut, already markets an anti-browning wash developed by another ARS team in the 1990’s for sliced apples and 18 other types of produce.

E. coli, Listeria, Salmonella and other foodborne pathogens sicken approximately 1 in 6 Americans (48 million people) each year. A recent U.S. outbreak of Salmonella associated with cucumbers sickened over 765 people in 36 states and killed 4.

First Step+ 10 is designed to reduce those numbers, and is expected to be used in the commercial flumes and rinse tanks that wash fresh produce, Gurtler says.

The ingredients are all classified as Generally Recognized as Safe (GRAS) by the U.S. Food and Drug Administration (FDA). The wash also has been approved for use in Canada; is U.S. Department of Agriculture (USDA) certified organic; is biodegradable; and does not affect the taste, texture, smell, or appearance of produce.

To save water, some food processors reuse wash water, a practice that can contaminate produce in subsequent washes. Along with reducing the risk of contamination, the new rinse will cut back on waste water because processors won’t have to replace water in their tanks as frequently.

To test First Step+ 10, Gurtler inoculated fresh cut apples, baby spinach, cantaloupe rind, and cherry tomatoes with highly resistant outbreak strains of E. coli O157:H7, Listeria, and Salmonella. He soaked them in the wash for 5 minutes and then measured pathogen levels in the wash water and on the produce. The antimicrobial wash reduced pathogen levels on the produce by 99.99 percent. It also rid the wash water of 100 percent of pathogens, making it safer to reuse.

Along with securing FDA approval, Gurtler and his collaborators at NatureSeal have filed a patent application and presented findings at scientific meetings.

ARS is USDA’s chief intramural scientific research agency.

Read more about this work in the January 2016 issue of AgResearch.

Produce: ‘Washing it good enough is going to maybe reduce the risk’

“People get ill,” says Ted Labuza, a professor of food science at the University of Minnesota. “If you really want to reduce your chances, washing it good enough is going to maybe reduce the risk.”

lettuce.skull.e.coli.O145Labuza says people should scrub, rather than rinse, their fruits and vegetables for 30 seconds.

“It should really be to one rhyme of Mary Had a Little Lamb,” he says.

In this video from the University of Minnesota Extension, the difference between a quick rinse and deep wash with your hands is dramatic.

“The friction is scraping it off, but you don’t want to scrape it off so much that you’re damaging the fruits and vegetables,” Labuza says.

He says a good wash will remove about 90% of the bacteria. For most healthy people, that’s enough to avoid getting sick from a variety of food-borne illnesses, like E. coli, salmonella and listeria. Older people and children are generally at greater risk.

Studies have shown that water and friction offers a similar clean to commercial vegetable washes or diluted vinegar.

But, in rare cases, the best cleaning won’t help. For example, leafy fruits and vegetables that have been irrigated with bacteria-infected water can be dangerous.

“We do know with things like lettuce and spinach, sometimes the bacteria crawls up through the channels and nothing is going to work there,” Labuza says.

Improving the food safety world, one blog post or conversation at a time

chicken.cook.thermometerUnlike the UK Food Standards Agency, which continues to insist on piping hot as a guide for consumers, the University of Illinois admitted they were wrong and updated their food safety advice for cooking turkeys.

With the help of some correspondents, I called out UI for recommending that turkeys be washed prior to cooking.

The head of UI Extension Communications e-mailed me today to say thank-you, and that their website has been updated with current best practices.

(He also said barfblog.com is “an outstanding resource” but I’m just doing what I do.)

Step away from the turkey, do not wash

You’d figure a website called food.com could get some basics right, but no, in the run-up to U.S. Thanksgiving next week, idiocracy rules.

wash.turkey.nov.14“Step 3 Rinse the Turkey

Remove the giblets and neck out of the turkey cavity. Rinse the turkey with cold water inside and out, removing any excess fat and leftover pin feathers. Dry the turkey by patting it with paper towels and place it in a large roasting pan.

TIP If you purchased a frozen turkey, allow about 5 hours of thawing per pound.”

Do not wash the poultry, unless you killed it yourself and need to remove the feathers.

(This is also satire) Terrorists threaten to attack UK by washing uncooked chicken

The terror threat level to the UK has been raised to the highest level since the Iraq war after suspicions grew that terrorists might have been reading all the recent articles about the deadly peril of washing uncooked chicken.

veryRawChickenIt is now known that washing raw chicken releases tiny water droplets filled with extreme poison into your kitchen, killing you and all your family instantly. Until this fact was established by government scientists, there was no explanation for the mysterious spate of deaths affecting everyone in the country who cooked chicken.

“Raw chicken washing-related deaths were running at approximately five million per year, in London alone,” explained chief government medical officer Brian Panic. “We’d always wondered why this might be, but no-one had ever put two and two together, despite the obvious presence of freshly washed chicken fillets near all the bodies.”

“The raw material isn’t a problem in itself, if safely handled until cooked right through,” (piping hot) he explained. “But the combination of uncooked poultry and washing has the potential to destroy civilization, and I’m not exaggerating.”

“Now this has become widely known, if would be simple for a terrorist organization, perhaps using chefs, to wash chicken in the major metropolitan centers, with potentially devastating effects.”

“This could be the most severe threat since terrorists learned to secretly not turn off their Kindles during take-off and landing.”

After a meeting of COBRA, the government’s emergency response and cookery committee, the military are guarding all airports close to branches of Tesco and Sainsbury’s and are monitoring suspects’ water usage for potential chicken-related spikes.

There was an unfortunate incident in Dunstable this morning when an armed response team shot dead a suspected sous-chef who turned out to be merely rinsing a nice piece of sea bass, but a government spokesman pointed out that this is the price of freedom.

Police are asking anyone with the smallest Campylobacter-contaminated nugget of information should come forward immediately for rapid grilling.

Thanks to my Scottish food safety friend for sending along this bit.

Follow the bug, collect the evidence: washing poultry not worth it

The food safety family’s curmudgeonly uncle, Pete Snyder (who really isn’t) would be happy that the don’t-wash-poultry crowd is gaining some traction.

Medical Daily writes that everyone should stop rinsing raw chicken under the faucet. Rather than reducing foodborne bacteria, rinsing poultry spreads pathogens to other surfaces in your kitchen via Dan Aykroyd Plays Julia Childwater splatter, exacerbating contamination rather than preventing it. Now, a new campaign urges the public to drop the habit, as it increases the risk of serious foodborne illnesses like those caused by Salmonella and Campylobacter bacteria. 

“There’s no reason, from a scientific point of view, to think you’re making it any safer, and in fact, you’re making it less safe,” said researcher Jennifer Quinlan, speaking to NPR. Quinlan is a food safety researcher at Drexel University in Philadelphia, and a spokesperson for “Don’t Wash Your Chicken” –– a university-backed public health campaign educating informing home cooks with video simulations and “photonovellas.”

“You should assume that if you have chicken, you have either Salmonella or Campylobacter bacteria on it, if not both,” said Quinlan. “If you wash it, you’re more likely to spray bacteria all over the kitchen and yourself.”

Concomitant focus-group studies funded by the U.S. Department of Agriculture (USDA) indicate that 90 per cent of the population washes their poultry before cooking it. After all, washing usually makes things both cleaner and safer. 

If you, like the majority of Americans, have been washing your chicken until now, campaign officials urge you to peruse the new reports, as well as the educational photonovellas. 

In addition, their “Germ-Vision” animation helps visualize the disconcerting spread of pathogens in your kitchen. 

Blame the consumer, Colorado-style: ‘three magic words clean, cook, chill’

Scrubbing cantaloupes with a brush would not have prevented 33 people from dying in 2011 in Colorado, and three from dying in Kentucky in 2012.

Washing produce of any kind is of little effectiveness – although it may make you feel better in a faith-based food safety system —  and that’s cantaloupe.salmonellawhy food safety starts on the farm.

Vicki Carlton, program manager of the Pueblo City-County Health Department’s consumer protection program told The Pueblo Chieftain raw fruits and vegetables are the biggest emerging problems, and that, “Back in the day, you got more locally.”

Like those cantaloupes from Colorado?

Justin Gage, an environmental health specialist with the health department, recommends washing bananas, too, because of bacteria and chemicals that are likely to be on the peel.

Has there been a microbial outbreak of anything associated with bananas?

Produce safety, US and UAE versions

From Abu Dhabi to Akron, Ohio, people are worried about the safety of leafy greens – spinach, lettuce, rocket, whatever.

Gulf News reports that locally grown fresh salad vegetables in the UAE are, according to academics, contaminated by dangerous bacteria because of unhygienic farm practices and improper food handling from the farm to the table.

They also warned nearly 43 per cent of water wells in the country are contaminated with bacteria that exceed the standard level of safe lettuceconsumption, even for irrigation of crops.

“If there is a serious epidemic or outbreak of life-threatening gastrointestinal disease we will know the source, namely, the contaminated salad greens we are eating nearly every day,” said Dr Dennis J. Russell, professor of biology, department of biology, chemistry and environmental science at the American University of Sharjah.

Research over the past five years showed the presence of persistent coliform and E. coli contamination sequestered within the leaves of the locally grown popular fresh salad vegetable knows locally as jarjeer (ccientific name rocket/rocca) and other salad greens, Dr Russells told Gulf News.

‘All of the samples of jarjeer were found contaminated with E. coli and 100 per cent of the latest samples were also contaminated with large amounts of Salmonella. Tests of other locally grown greens show they too are contaminated with these bacteria, although to a lesser extent,” Dr Russell said.

Michael Doyle, director of the Center for Food Safety at the University of Georgia told the Daily Herald that a recent study released by the Centers for Disease Control and Prevention fingered produce as the leading cause of food poisoning in the U.S.

Doyle said the more cracks and grooves on the skin of a fruit or vegetable, the more easily bacteria can hide. Melons also have a neutral pH, so they offer a perfect growing environment for bacteria.

The problem of contaminated melons is often made worse by grocery stores that sell cut pieces, but often don’t store them in a cold enough lettuce.skull.e.coli.O145environment.

Doyle recalls walking into an upscale grocery store in South Carolina one summer, where a metal tank with ice in the bottom was filled with containers of cut melon. The bottom inch of the containers was inside the ice, leaving the majority of the melon in an environment warm enough for bacteria to multiply rapidly.

In the CDC’s new study, however, leafy greens like lettuce and spinach were revealed as the worst culprits for food poisoning in the study period, between 1998 and 2008.

Salad greens marked “washed and ready to eat” or “triple-washed” remain an area of debate among food safety experts.

Some experts contend that the triple-washing with chlorine that takes place during processing is enough to kill what bacteria can be killed, and advise against washing bagged greens because the risk of cross-contamination in the home kitchen is a greater concern.

Doyle says not to buy bagged greens at all. He advises buying whole heads of lettuce or greens, removing the outer surface layers where bacteria is most likely to be present, and then washing the greens under cold running water.

Doyle has conducted studies that show the cutting and bagging of lettuce in processing plants can actually trap bacteria inside the lettuce leaves, meaning that no amount of scrubbing or washing will ever get rid of the germs. If greens are cut before they are washed — as they commonly are during processing — the bacteria become internalized by the leaves, trapping the germs inside the produce.

As risky as bagged greens can be, Doyle said an even greater concern should be the consumption of raw sprouts like bean and alfalfa.

He believes the only reason they weren’t first on the list of illness-causing produce in the CDC study is that folks just don’t eat nearly as many of them as they do items like lettuce, tomatoes or melon.

He said sprouts, due to their high levels of contamination, should never be consumed raw.

Fail: Cargill recommends washing turkey

Cargill, the owners of the Honeysuckle White brand of turkey, may want to update its turkey prep instructions; and maybe before Christmas.

A barfblog.com reader sent in this label; I enlarged it but my aging eyes still couldn’t make out what it said.

According to the Honeysuckle White website,

“Leave the turkey in its original wrapping and place it on a tray in your refrigerator. Allow five hours of defrosting time per pound. For example, a 14-19 lb. turkey will need 3-4 days to thoroughly defrost. If your turkey hasn’t completely thawed by the time you’re ready to cook it, place it under cold, running water to accelerate the thawing process.”

This will spread Salmonella, Campylobacter and others throughout your kitchen, at home or in a restaurant.

Cargill also recommends, “Rinse the turkey both inside and out with cool water and pat it dry with paper towels.”

Guess Cargill’s not up on the science: don’t wash that bird (unless you killed it in your backyard with a bow and arrow in Kansas, sure, wash it to help get the feathers out; but I thought Cargill had sorta figured that out).