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Researchers at the University of Texas at Dallas have created a portable food safety device they hope will one day be used at every level of the food industry—from processing facilities to home kitchens.

Called READ FWDx, short for Rapid Electroanalytic Diagnostic Food Water Diagnosis, this proof-of-concept device is designed to detect unwanted food-borne bacteria such as E. coli, listeria and salmonella. It can also pick up on common herbicides, including paraquat dichloride and glyphosate and chemicals like antibiotics.

"We have so many gadgets that measure all our body parameters, like heart rate, blood pressure and blood sugar," said Shalini Prasad, a professor of bioengineering and biomedical engineering at the University of Texas at Dallas, who cofounded EnLiSense to commercialize the device and other sensor technologies her lab has developed. "But what do we have in the context of our food?"

The research comes as food recalls are on the rise. According to some estimates, food recalls increased by 15% between 2020 and 2024. Another report published in February found that the U.S. The Food and Drug Administration counted 241 food and beverage recalls and alerts in 2024, an increase of 8% compared to 2023. In the last few months, food recalls affecting Texas have ranged from cucumbers to ground beef, enoki mushrooms and various other food products.

Recalls can happen for many reasons, said Melanie Firestone, a professor of environmental health sciences at the University of Minnesota School of Public Health, who is not involved with READ FWDx's development. Some recalls are associated with outbreaks of bacteria like listeria or salmonella, while others occur when products are misbranded or mislabeled or if there's an undeclared allergen.

"Anytime something goes wrong in the food system, that is an opportunity to either identify hazards we may not have known about or were previously unrecognized," Firestone said. "That also allows us to begin to understand the root causes and implement better prevention measures."

The recent rise in recalls is more so due to improved traceability and food safety technologies rather than a decline in such measures, said Francisco Diez-Gonzalez, director of the Center for Food Safety at the University of Georgia, who is also not involved with READ FWDx's development.

Making food safety portable

Technologies aimed at monitoring food contaminants have been around for several decades. Traditional methods include high-performance liquid chromatography, a kind of super-powered filter that separates ingredients in a mixture one molecule at a time; mass spectrometry, a tool that weighs and identifies molecules based on their unique signatures; and enzyme-linked immunosorbent assay (also known as ELISA), which uses antibodies to zero in on and measure specific substances.

But these methods require specialized, costly lab equipment and aren't exactly portable, said Sriram Muthukumar, EnLiSense's co-founder, who is married to Prasad and collaborated with her on the new food safety device.

Another challenge has to do with time and efficiency. Because testing for a biologic, say a virus or bacteria, requires different techniques than for a chemical like a herbicide, testing for both can't be done at once, Prasad said.

The demand for efficient, precise yet portable detection has led, in recent years, to the burgeoning field of sensors that replace conventional analytical techniques and provide easy-to-read detectable signals. Electrochemical sensing is one of those technologies being tested for food contamination. EnLiSense's READ FWDx, in particular, uses something called adaptive electrochemical impedance spectroscopy.

Prasad explained that when a sample—whether a drop of water from cleaning store-bought carrots or liquid from crushed meat—is placed on the sensor, it scans all the layers of the sample for the contaminant. The abundance of any particular contaminant will dictate its total electrical charge and dielectric properties, or ability to conduct electricity.

"A higher concentration will have a different charge and different dielectric properties than your lower concentration or low abundant material," Prasad said. "You're able to tune [the sensor] like how you would tune a radio. … So that means you're not measuring one, two or three of the sample type, you're measuring multiple things of different types on the same platform."

The chip that's read by the device is made up of 16 sensors, each able to detect multiple contaminants. (The device itself delivers results within seven minutes.) Determining which contaminants to test for is based on the latest data from the U.S. Centers for Disease Control and Prevention.

"So it's similar to plug and play in a sense where we have a biological panel, like a salmonella or E. coli panel, that's customized to one sample," said Vikram Narayanan Dhamu, a former graduate student in Prasad's lab and now EnLiSense's director of systems engineering and operations.

He added the chip's customizability allows the sensors to be easily swapped out for ones detecting fungal or viral contaminants, or chemicals such as antibiotics or pesticides.

Prasad's lab has published several papers demonstrating READ FWDx's performance and precision.

A June 2024 published in the journal Biosensors showed the portable device could detect and quantify a pathogenic strain of E. coli, known as E. coli O157:H7, within five minutes.

A May study also in Biosensors found READ FWDx could pick up on zearalenone, a fungal mycotoxin found in moldy grains such as corn, wheat and barley. Not only does this contaminant present a risk to cereal food safety, it can also threaten livestock health.

Prasad and her colleagues also showed the device's sensor could pick up on two contaminants simultaneously—zearalenone and aflatoxin B1, a mycotoxin produced by the fungus Aspergillus flavus that's known to cause cancer in animals—in another study published this April.

Incentivizing change

In the future, Prasad and the EnLiSense team would like READ FWDx to be available to everyday consumers. If the portable device does become available to the public, each chip will be single-use and have a shelf life of up to a year to keep it storable at room temperature. (Prasad said the chip may still work after a year but not with the same level of sensitivity.)

Ultimately, they hope to get manufacturers, commercial labs or food chains interested in READ FWDx as a means of point-of-care testing, when a test takes place on-site, specifically in situations where rapid turnaround is necessary.

At the manufacturing level, however, where food safety protocols are already in place, it's an open question whether a portable device like this will lead to more frequent batch testing, where only small samples of the larger supply are tested, said Diez-Gonzalez of the University of Georgia.

"Most of the [quality control] testing is based on a sample," Diez-Gonzalez said. "They are not necessarily proportionally representative for, let's say, a batch of product. … We don't have any technology that can actually screen every food item so far."

Prasad is optimistic that READ FWDx's ability to deliver results rapidly and accurately will encourage manufacturers to do more quality control screenings.

"The vision with the READ FWDx is to increase the number of point-in-time batch tests because it becomes accessible and affordable," Prasad said. "This has broadly been regarded by manufacturers as a stable and scalable strategy to accurately identify food contamination and reduce product loss as well as reduce exposures."

Whether manufacturers will adopt the device—and whether the average shopper will screen their groceries at home—remains to be seen. But with food-borne illness and contamination still a persistent threat, tools like READ FWDx offer a glimpse into the strides scientists are taking to ensure our foods are safe to eat.

2025 The Dallas Morning News. Distributed by Tribune Content Agency, LLC.