Fantastic feasts: How CFIA's Burnaby Lab guards your food against fiendish fungus

Don't you hate it when 1 little thing causes a ton of trouble? It's always the small things that lead to the biggest problems.

Take the classic example of forgetting to check some berries then finding white fluff covering them before you even get a taste, or missing a tiny blue spot on some bread and chucking it in the compost the next day because it is covered. Everyone has had something like that happen to them at some point, right? Well, that mold you are seeing is a fungus.

While fungus on your food is an off-putting inconvenience nowadays, in the past it was enough to get you burned at the stake!

A plant with Claviceps fungus
A plant with Claviceps fungus

Centuries ago, a type of fungus called Claviceps plagued European and North American farms. The fungus itself isn't that bad, but it produces chemicals called mycotoxins that have nasty effects on people, including delusions, psychosis, and seizure-like spasms. Claviceps gained its infamous name, "ergot of rye," because of its tendency to grow on rye grains. Since rye is a common baking ingredient, ergot has had a long history of creeping into the food people eat, leading to all types of trouble.

In the fall of 1691, residents of Salem, Massachusetts, celebrated a successful rye harvest. However, that year's rainy spring made ideal conditions for ergot to grow. Suddenly, local women who made food from rye began to show "signs of possession by evil spirits." These "signs," mainly hallucinations and spasms, were suspiciously similar to symptoms of ergot poisoning.

Most of these women were regularly eating and working with raw and cooked rye and did not know they were most likely in contact with ergot-contaminated foods. As a result, over 200 people were accused of witchcraft and 20 were executed. Interestingly, after a warm and dry spring the following year, the ergot dried up and Salem's "bewitchments" suddenly ended, too.

The Salem witch trials are not the only time ergot wrought havoc on a community. In 1518, residents of Strasbourg, France, were baffled when 400 residents began dancing uncontrollably. The town hired musicians to play for the dancers until they collapsed from exhaustion, believing that would calm the spirits possessing them. Little did they know, the victims had been exposed to a strain of ergot toxins found in the modern-day hallucinogenic LSD. It turns out LSD is a product of ergot fungus. Imagine how scary it was for early villagers to see their neighbours suddenly become zany, not knowing it was caused by fungus-filled food!

Ergot outbreaks may seem like a thing of the past, but warming climates and changing weather have created a perfect environment for fungus to grow on grains and fruit. However, protecting plant and animal health and keeping food safe is what CFIA does. Fighting fiendish fungus is something scientists at our Burnaby Laboratory do regularly. To fight this foe, our scientists use a complex blend of chemistry and biology to root out even the tiniest traces of toxins, including ergot of rye.

Finding fungus

The CFIA's Burnaby laboratory
The CFIA's Burnaby laboratory

To test for ergot, our scientists at the Burnaby Laboratory separate the chemical components and toxins in a sample by binding them to special beads in a column. Once background components are washed away, the bound toxins are released from the beads by changing the conditions. Scientists can identify which components are in a sample based on the speed and conditions under which each chemical detaches from the column. Food samples that contain high amounts of ergot toxins are deemed unfit to eat.

The scientists use similar chemical testing methods to spot and limit exposure to many other mycotoxins, including patulin. Historically, ergot-infested grains were a major cause of illness. Now, fruit gardens can be an overlooked area for fungi to fester. Backyard apple and cherry trees aren't usually maintained to the same standard as commercial orchards, and without regular picking and disposal, rotting fruit may spread fungi. Fruit supports a variety of fungi, including species that can produce the toxin patulin, known to cause genetic mutation at high levels and even cancer. Responding to simple and easily identifiable quality cues is still the best way to prevent patulin poisoning: don't process or eat damaged or rotting fruit, simply compost it instead.

While our scientists at the Burnaby Lab don't perform exorcisms or witch trials, the sheer number of tests they complete is nothing short of magic. CFIA scientists at the Burnaby Laboratory can test for a wide range of bugs and chemical contaminants. All this helps to ensure that our fruit, grains and food are safe to eat. With nearly 38 million Canadians eating grain and fruit products each day, there is no wondering why our Burnaby scientists need a trove of tests to keep Canadians safe.

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