Food Science/e. coli
I am a vegan due to some health concerns. I have lately been seeing what seems to be an increase in infections of e. coli from apparent vegetable sources. Is this a recent development, and if so, do you know what might be contributing to this?
What processes will destroy e. coli on vegetables? Is washing in a salad spinner, for example, sufficient for raw vegetables for a salad?
The short answer to your questions -
Media coverage of e coli infections is over-emphasizing, repetitious and misreporting.
E Coli contaminations dropped 50% over the 1995-2010 period, and remain low.
E Coli on vegetables or fruits are always a contamination from processing or packaging facilities.
The more frequently a food crop is transferred, transported and processed, the higher the risk of contamination from a variety of pathogens than can thrive in/on poorly maintained food processing facilities/equipment.
A full head of lettuce (Bibb to Iceberg to Romaine) runs a much reduced chance of being contaminated through its journey from farm to market. It risks contamination from harvesting equipment, whole food washing, transportation to market, your food-market's sanitary practices and conditions (including workers).
Contamination will be surface contamination.
Removing browned/damaged parts of the lettuce, then soaking and spinning, is sufficient to eliminate the risk of symptomatic infection with e coli or other pathogens.
Using distilled water is safer and more effective than tap water (which has been known to carry pathogens).
But take that same head of lettuce, harvest it, transport it to a processing plant, put it on a conveyor belt and wash, chop (another conveyor), wash again with added disinfectant (another conveyor), spin, and then bag it... you have exposed it many times to people and equipment that can contaminate more and more exposed surface area (as well as cut surfaces, to which bacteria can adhere better).
Buying a chopped, bagged & prepared salad (while convenient) exposes you to increased risks you don't encounter with at-home whole-food preparation, and/or increased preservative chemical residue.
Even so, based on published records of food poisonings, the risk of contamination that leads to symptoms using even chopped and bagged salad ingredients is very low (but well publicized, when it does happen!)
You ask about "destroy[ing] e coli on vegetables". You can't destroy all bacteria on salad ingredients without sterilizing the food, which will destroy not only the bacteria but the appeal, palatability and nutrition whole-food salads offer.
We currently have no process that will destroy all bacteria on lettuce that won't also make the lettuce unfit for a salad (whether its contamination with disinfectant or destruction through radiation). None of these methods are safer than careful soaking and spinning of your leafy greens or a baking soda scrub/wash of your other vegetables and fruits.
Using distilled water is safer and as-effective/more-effective than tap water (which has been known to carry pathogens) or vegetable disinfectant products (advertised & sold in most supermarketsí produce sections).
That was a short answer... now for some of the rest of the story (and I describe my own cleaning regimen at the end if you want to skip these other details).
Our perception is that e coli contaminations are on the rise, but the media selectively emphasizes and constantly repeats food contamination stories which are RELATED to the deaths of hundreds each year (people with already existing chronic health problems are the ones that die from pathogenic microbe food poisoning).
Compare those deaths to the HUNDREDS OF THOUSANDS caused by pharmaceuticals (legal and illegal use) every year.
Over 100,000 deaths occur from PROPERLY PRESCRIBED AND CORRECTLY TAKEN medications every year!
EVERYONE in the country eats food, but a much smaller percentage of us take medications regularly, yet it is pharmaceuticals that cause so much more death and injury than food poisonings do.
Where is the repetitive media reporting on the continuing deaths an injuries caused by drugs? Or even products from China? We only here about a fraction of those incidents, and they quietly slip off the radar screen.
In depth reporting on those issues are less frequent and less emphasized.
One indication of the depth of the drug problem is commercials from law firms (which most of us fast forward through or ignore) about injuries and deaths caused by the proper use of prescription drugs.
We would be seeing law-firm-sponsored commercials about vaccine injuries/deaths, except there is a law that forbids anyone suing vaccine makers for injuries or deaths (The 1986 National Childhood Vaccine Injury Act - NCVIA).
There was recently a bill slipped into a major piece of legislation in our Congress that would have made Monsanto and other biotech organizations immune from lawsuits over their DNA-altered food products. Luckily, it was found and pulled out of the larger legislation, but it was close.
Why would food producers need to be protected like that? Is there something inherently wrong with genetically modified organisms, crops and animals?
E coli contaminations of food products, from 1995 to 2010, dropped by 50%.
When the media decides to devote a lot of coverage to e coli contaminations that still happen, stoke rumors that amending soil with manure is the cause, and don't do proper follow-up reports, they generate buzz/viewers/revenue and don't explain the real cause or how we can protect ourselves.
They also cause us to have repeating memories of these contaminations, making them seem more frequent and deadly than they actually are.
It is rare to see follow-up reporting explaining exactly where the contamination happened. I have followed up on some contaminations and most are never explained, just theories and best guesses.
The reports/reporters also make the public feel they are doing responsible reporting (by protecting us from bad food), but they are not.
By the time food poisoning is recognized to be sourced from a certain manufacturer, and a voluntary recall issued, the contaminated batch of food is 100% distributed, and mostly consumed.
The reporting does help in cases where producers or distributors refuse to admit there is a problem and continue the practices that led to the poisoning... causing more poisonings to occur. The recent conviction of a peanut butter manufacturer who ignored the findings of contamination is an example of what should happen more broadly when manufacturers ignore or misinform (Vioxx and Pargluva are examples where executives got a pass on criminal prosecution even though they marketed, or tried to market, drugs that they knew were injuring and killing their patients).
Going through a variety of web pages from CDC, FDA, USDA, NIH, medical websites like WebMD and the media I have found that most of the contamination regarding e coli is in the information presented for public consumption.
What news we are fed is mostly contaminated by groundless fear mongering, incorrect information and lack of follow-up reporting of the investigations.
Most of that misinformation either indirectly or directly supports food irradiation as a necessary tool to fight e coli contamination (or other pathogens) of our food crops and animals.
Food irradiation is ineffective in eliminating e coli (or ANY pathogen) from thin, fragile, low-density foods like romaine lettuce, baby spinach, collards etc., without causing extensive damage to the food's appearance, taste and nutritional content.
Many of these same sources also imply organic growing methods (manure used as fertilizer) are a source of e coli contamination, but this is also wrong.
Manure is worked into soil LONG BEFORE planting (to allow the breakdown and incorporation of nutrients into the soil). Any e coli in a manure/soil mixture are dramatically reduced or die out, unable to compete with other soil microorganisms. Soil in an environment hostile to e coli (wrong temperature, scarcity of suitable nutrients, too many competing well-adapted soil microorganisms).
There are also rumors that roots can take up e coli from the soil and "internalize" the contaminating bacteria. That is simply a gross error or a lie, not supported by any evidence or studies looking for exactly that kind of contamination route.
A recent Purdue study claimed that contaminating seedlings led to internalization of bacteria in plants. But in the study the researchers admit there might have been contamination from the outside when they sliced into the plant, making it appear the bacteria were surviving inside. They also used high concentrations of bacteria not found in soil.
A quick review of the Purdue website shows they are heavily invested in doing research supporting food irradiation.
My recommendation to you is to first buy organic (if you can afford it), then non-GMO veggies. If you review some of my other answers you can find out why I oppose unlabeled GMO veggies and fruits in our marketplaces.
One very important reason (related to e coli and other bacteria) is that each type GMO almost always has a different antibiotic resistance gene. These genes are proved to transfer to gut bacteria in insects (honeybees), animals (cattle eating GMO feed) and people. Bacteria are very adept at absorbing and utilizing genetic material.
The antibiotic resistance genes nearly always in GMO foods are probably related to the severe problem of anti-biotic resistance facing farmers and doctors today. That is another in a LONG list of reasons to go organic or Non-GMO!
One tomato I can recommend is Tasti-Lee, the most flavorful packaged tomato I have ever eaten (and they are non-GMO and very competitively priced!!).
Unfortunately, they are carried only by Wal-Mart in our area. But I am talking to other retailers that I normally shop at to get that line of tomato (Trader Joe's, Farm Fresh, Fresh Market - Fresh Market is now carrying a small supply).
We are getting our first Whole Foods Market, so I am excited to shop there and see what is available.
To get more information for going "non-GMO" please visit this website -
Listings of Non-GMO foods - http://www.nongmoproject.org/find-non-gmo/search-participating-products/
At that last link you can find restaurants that are Non-GMO, retailers that are non-GMO supporters, and an I-Phone application.
Non-GMO Project Supporting retailers (Search by state) - http://www.nongmoproject.org/find-non-gmo/search-retailer-endorsers/
Non-GMO Project Restaurants - (Currently being re-done) - http://www.nongmoproject.org/find-non-gmo/find-restaurants/
Non-GMO Shopping Guide - Two versions
Fighting the hijacking of our food supply, by Biotech organizations interested in only making a profit, is the most important thing we can do for our kids. GMO are the most contaminated and unsafe foods we can eat. They have all the problems of conventionally produced food crops with added contaminations and nutritional changes associated with alteration of crop DNA, production of insecticides in the crops and large amounts of herbicides now sprayed on these crops. And that is the short version of what we know is wrong with genetically modifying our food supply.
Finally, here is the way that I clean my produce.
Washing vegetables is sufficient to remove any forms of e coli as well as other pathogenic bacteria on vegetable surfaces.
Distilled water soaking then spinning is the technique I recommend for lettuce or other leafy vegetables, but SAFE tap water adds chlorine and/or chloramine (combination of ammonia and chlorine, used in many water treatment facilities) as disinfectants.
For other vegetables and fruits I use tap water and a hand-scrubbing with a good amount of baking soda.
I keep an eight ounce container, with a flip-open-lid (lid is about the size of a milk container's opening), filled with baking soda by my kitchen sink. Part of the routine after food shopping is to take most of the fruit and veggies to the sink for scrubbing.
Some I clean as I need them (lettuce, grapes and potatoes, for instance), others (like oranges or apples) I clean whatever I have brought home.
To clean sturdy dense veggies, I rinse, sprinkle a good amount of baking soda on, drizzle enough water to make a paste, hand-scrub, rinse and drain.
With lettuce or other leafy greens, I remove brown/damaged areas, I soak in cold distilled water with a little baking soda, then rinse and spin.
Once this becomes routine, and you appreciate knowing your food is clean, you will develop your own tweaks for this way of cleaning and it will get faster.
Then you will have the peace of mind you are searching for regarding food safety.
Please ask follow-up questions if you need more information or clarification.
I hope I have helped,