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Take Care! Food is out to kill us!

These peppercorns totally Salmonella free (I don’t recommending licking the screen) Image by congerdesign from Pixabay

Bacteria shouldn’t survive on dry food such as flour, flaxseed meal, chocolate and black pepper. Or so we thought. Food science has a mysterious measurement called water activity which shows how much water is present in a food that is available for microorganism growth. Moisture content lets us know the total amount of water in a food. Water activity is a key factor in food preservation; like pH. Water activity runs from 0, which is no water to 1.0 which is pure water. Food scientists have known that if water activity is less than 0.6 no microorganism growth can occur. In fact, bacteria need a water activity of 0.85 before they can grow. So why did Norway just have an outbreak which was most likely caused by a dried nut mix?

A pile of tiny brown seeds
A pile of flax seeds from Alexdante at Pixabay

I am a very frustrated consumer and food science professional. I have been doing a hazard analysis and looking up all the ingredients I and my clients use. Pretty much every ingredient, especially if they are processed, has been involved in causing foodborne illness or been part of a recall because they might contain pathogens. This is pretty shocking as this implies we have a serious problem with food manufacturing in the US. Initially, I thought that recalls showed that the system is working, especially if no one became ill. Well it is in a way, if food is withdrawn from the market before anyone gets ill. However, managing a food supply by responding to the potential threat of Salmonella etc. AFTER they have been found in a manufacturing facility is NOT a safe food system. So now I believe that recalls show we have a  broken food system.

On top of all that, the American Ambassador to Great Britain claims that American agriculture is science and technology based whereas the EU uses traditional methods which should be in a museum! That will please the Germans! Britons, so far, are unimpressed with the idea of an open trade agreement with the US especially around food. There have been quite a few rebuttals from British farmers. James Rebank had a couple of great responses on Instagram. Additionally, Sustain showed that there are more foodborne illnesses per capita in the US compared to the UK, refuting his claim that US food manufacturing is safer than British ag. Did you know that your US chicken was chlorine rinsed?

Picture of a raw chicken ready for grilling with potatoes, tomatoes, onions, and a head of garlic nearby.
Chicken is ready for grilling. Hopefully those tomatoes are going to be grilled too.
Image by RitaE from Pixabay

What have we done?

  • Why are so many people in the US getting ill from food poisoning?
  • How many products made by small food businesses fall through the cracks?
  • How many small manufacturers check to see if they have bacteria in their facility?
  • How many food entrepreneurs consider food safety serious issue equal to marketing?

There has to be a better more sustainable, more resilient way to produce food on a large scale. The large manufacturers must know the risks. Do small food businesses? Is local food the answer? What do you think are the next steps to improving our food system? Comment, share, and keep the conversation going.

Noncompliance = Death

Noncompliance equals death seems to be turning into my tagline. Am I being over the top? Sadly not. According to the CDC, about 3000 people die from foodborne illness each year. That’s not counting the ones left serious/gravely ill. Which pathogens are most dangerous? For healthy adults, most pathogens will give a few days of discomfort (vomiting, diarrhea, fever). However, the response for at risk groups (young children, elderly adults, immunocompromised and pregnant individuals) is much more severe and more likely to be fatal. There are many food pathogens. The CDC has data showing which are more likely to cause illness, hospitalization, death. This is within the known causes of foodborne illness; more than 50% of cases remain unresolved.

Clostridium botulinum

Image Description: Rod shaped bacteria colored blue and orange on a black background.

In this post I am focusing on Clostridium botulinum. I was reminded of the horrors of botulism by a recent article in Gastro Obscura as this is a particularly unpleasant way to die. Fortunately C. botulinum doesn’t kill many people today because we know how to prevent it from growing and producing its toxin. Many food safety regulations are based around preventing C. botulinum from killing people.

C. botulinum is a problem in canned and bottled food because there is little or no oxygen present. The lack of oxygen reduces the chance of spoilage organisms but if we remove oxygen and C. botulinum will thrive. These bacteria are known as obligate anaerobes as they cannot survive if oxygen is present.

Image description: Clip art of three cans containing vegetables.

There are two types of heat treatment you can use to control C. botulinum, depending on whether your food is high in acid or not. C. botulinum does not like acid, so high acid foods can be boiled for a set time to kill the bacteria. Low acid foods, especially if they also are high moisture, must be heated to temperatures well above boiling. C. botulinum produces spores when under stress conditions that would kill other bacteria, such as Listeria or Salmonella spps. Spores are like the seeds for the bacteria and when conditions improve these spores germinate and release botulinum toxin, aka botox. Yes, the botulinum toxin which causes botulism is Botox and is used to remove wrinkles and helps a friend with her migraines..

To destroy C. botulinum and prevent spores in low acid food requires a temperature above boiling (>240 oF/116 oC; guide to temperatures and food preservation). This can be reached at home in a pressure canner. To show that food has been manufactured properly, temperature must be measured with a calibrated thermometer and records must be kept.

Processed food is divided into low acid and high acid food because C. botulinum cannot survive in high acid foods. People who make canned tomatoes and other mid-acid foods measure the acid content by measuring pH and reduce the pH so that the final product has a pH below 4.6 (more about pH and food). The acid level in food is measured as pH with a calibrated pH meter and records must be kept.

Reducing the water content can also reduce C. botulinum. Food technologists measure water activity (more about water activity) which is a more accurate measurement than moisture content of whether bacteria will grow in a food. To stop bacteria from growing, water activity should be below 0.85. This can be measured with a calibrated water activity meter and records must be kept.

In summary, while C. botulinum rarely causes foodborne illness, when it does it causes death. Therefore, the food entrepreneur must have constant vigilance to ensure that the food they are making is low acid, low moisture and/or heat treated and records to match their control method..

References

  1. Lydia Zuraw The 5 Most Dangerous Pathogens Food Safety News, Sept 14, 2015; Site last visited on Nov 26 2018.
  2. CDC Burden of Foodborne Illness: Findings; July 15, 2016; Site last visited on Nov 26 2018.
  3. CDC Home Canned Foods; October 4, 2018; Site last visited Nov 29 2018.
  4. CDC Botulism; October 4, 2018; Site last visited Nov 30 2018.
  5. FDA Guidance for Commercial Processors of Acidified & Low-Acid Canned Foods; March 14 2018; Site lasted visited Nov 30 2018.
  6. Tal Mcthenia The Lethal Lunch That Shook Scotland Atlas Obscura, Nov 15, 2018; site last visited Nov 30 2018.
  7. Julie A. Albrecht Clostridium botulinum University of Nebraska-Lincoln, no publication date; site last visited Nov 30 2018.
  8. Carolyn L. McCarty and co workers Notes from the Field: Large Outbreak of Botulism Associated with a Church Potluck Meal — Ohio, 2015; CDC MMWR, 64 (29); 802-803, July 31, 2015; site last visited Nov 30 2018.
  9. News Desk Ohio Botulism Outbreak: 1 Dead, 23 Hospitalized After Potluck Food Safety News, April 21 2015; site last visited Nov 29 2018
  10. National Center for Home Food Preservation, General Canning Information: Temperatures for food preservation Feb 2, 2017; Site last visited Nov 30 2018