Electrical engineering doctoral student Wen-Ding “Eric” Huang wants to save you from buying food that’s past its prime.

Eric earned a bachelor’s degree at Feng Chia University, a highly-respected private institution in Taiwan, but decided to attend UT Arlington for his graduate studies. “I was interested in automatic controls and learned that Dr. Frank Lewis was a leader in this field,” he said. “I also learned that UT Arlington had a strong faculty in microelectromechanical devices, which I was also interested in.”

As it turned out, Eric ended up conducting research in neither of these. Instead, he’s been working with Dr. J.C. Chiao on various sensors. One of these is a freshness sensor for foods.

“It came about in an odd way,” Eric said. “My father, a university professor, has a discerning taste in sausages. He can identify all sorts of flavors that separate one type from another. When I mentioned I was looking for a high-demand commercial application for sensors, he suggested food.”

That led Eric to create a multisensory array on a flexible substrate that can be packaged along with various foods. The sensors are designed to detect changes in pH – a measure of the amount of acid or alkaline in a solution or substance.

“This is trickier than it sounds,” said Eric, “because it can’t be applied the same way for every food group or even different things within a group. For instance, changes in pH levels in fish take place at different rates, depending on the species. So, even though they may have the same pH, fish in one package could be fresh while another could be bad.”

Also, changes in pH aren’t always an indication that something is bad. Anyone who is an aficionado of brewed beverages can tell you that the fermentation process, either properly or improperly applied, can affect a huge change in flavor and appearance.

“The consumer may not ever be the one to pull a spoiled product from the shelf. I’m working on a version of the sensor that operates somewhat like an RFID chip so the grocer can pass a transceiver across the package and get a reading without looking at the sensor. Even if the ‘sell by’ date hasn’t been reached, the product could have gone bad because of improper shipping or storage.”

Eric has been perfecting his sensor array for three years and has applied for a patent. You might be seeing them in your local grocery within a couple of years.