The cytometer — the large, black device on the counter — looks for bacteria in plants. Darrick Gates, an undergraduate senior biology major, analyzes the results on a computer. Courtesy GVSU
The threat of E. coli has prompted a Grand Valley State University researcher to find the bacteria in food before it hits the market for consumption.
Kevin Strychar, an ecological researcher at the university’s Annis Water Resources Institute in Muskegon, was awarded a $96,007 grant from the Michigan Department of Agriculture and Rural Development to test the use of an imaging flow cytometer to discover E. coli contamination in food as it is brought from harvest.
“The imaging flow cytometer has a microscope and a laser,” Strychar said. “Every particle that passes through that laser beam, we get a bunch of information and every time the particle passes, we also get a picture of the particle and it helps to characterize particles like E. coli rapidly.”
Strychar said the tool can identify whether or not a food particle has E. coli bacteria in 20 seconds, which is faster than what is being used now.
Polymerase chain reaction is the technique currently being used by researchers, which takes about two hours to detect bacteria in food, according to Strychar, who has been a researcher at the Annis Water Resources Institute for five years. He said he is focusing on testing water that is sprayed on blueberries.
Strychar said he thinks some farmers are using reclaimed water that goes to the sewage plant and then is treated, cleaned up and screened before being used again by individuals like farmers. Although the water may be treated and cleaned, he said there is a problem when the water is used to water crops because there is an “introduction of E. coli, dangerous E. coli, the ones that can really kill.”
The grant allows Strychar and his research group at GVSU to get blueberries from farms across the state to test them, but he said he and his fellow researchers are unaware of where in Michigan the blueberries are coming from in order to conduct unbiased research.
He said his hope is for the industry to have more than one method of testing.
“The end product is rather than waiting two hours or six hours, which means, in theory, that the sample of the product can spoil, the end product would be that within 60 seconds or less, you can tell a farmer whether their produce is safe for human consumption,” Strychar said. “And if it is not, rather than waiting a few days, the farmer can make an immediate decision whether to re-sterilize or re-irrigate or whatever method they use to clean their produce, they can (make) an on-site, immediate (decision) as opposed to having to wait 12 hours or two days or three days.”
Although the experimental tool is able to detect E. coli, according to Strychar, he said there is a lot more research left to be done, including proving to the state that it works.
“The state will set up trial independent labs, and all three labs will sample and, hopefully, confirm that it works,” he said. “If it does, then it is up to the government, and then, I assume, what the government will then do is institute legislation that would require this method of analysis.”
The research for rapid E. coli testing equipment in Michigan was funded in response to the Food Safety Modernization Act, which was enacted in 2011. Tim Slawinski, director of the food and dairy division of the MDARD, said GVSU’s research is significant because, in January 2022, farmers will be required to test agricultural water for E. coli as part of a series of changes over the next few years that will be implemented in the FSMA.
The first set of requirements were put into place regarding employee hygiene. Before the FSMA, Slawinski said there were no regulatory requirements to test water for E. coli.
“I look forward to the results because the intent is to figure out if (the image flow cytometer) is feasible,” he said. “If this is something that can resolve some logistical concerns and then if it is something that can be used nationwide, if it is determined that it is a reasonable way to test water, then other (companies) across the nation can decide, ‘Hey, I can buy this piece of equipment and maybe implement a program that can use that.’ It could provide another option to test water.”