We’ve all been there: holding the fridge door open as we cast a skeptical eye over that 4-day old package of meat, wondering if it’s still good or if maybe we’re better off throwing it out and ordering a pizza for dinner. I personally try and do the majority of my grocery shopping on the weekends, so when the end if the week rolls around and I still haven’t cooked something, it’s tempting to call it a wash and stave off the food poisoning I live in constant fear of. I will say that I’ve made drastic improvements in conquering my intense food paranoia and often abide by a 5-6 day leeway on leftovers, but I do have my moments. I still throw out perfectly good food just because it’s been in the fridge longer than the number of days suggested by the FDA, or because the package is past its expiration date. So when I heard that there is now a device to measure if meat is past its prime or not, I was tempted to e-mail the researchers to be first in line for one. Because this is truly a game changer, not only for the ultra food conscious like myself, but also for every restaurant, butcher shop, and grocery store in the world.
Developed at MIT in the lab of Timothy Swager, the new sensor can measure the metabolic degradation of meat and fish to determine if they are safe. This can help prevent that inevitable moment of getting our noses too close to bad meat, as the sensor detects the gases produced by decay. When meat goes bad, proteins are broken down into molecules classified as biogenic amines. These biogenic amines are produced through the natural breakdown of proteins as well as byproducts of bacterial growth. They can be detected and measured to evaluate food freshness; however testing for these compounds was previously a lengthy and expensive process, not something that could be done without extensive equipment and on a regular basis.
Enter the carbon nanotubes, which can detect the biogenic amines in their gaseous form when meat decays. These nanotubes contain the metallic element cobalt, which can bind to the nitrogen groups in amine compounds. It is this chemical modification that allows the electric current of the nanotube to fluctuate in the presence of specific gases. Once amines bind the cobalt, the electrical resistance of the carbon nanotube increases, and it is this resistance that is measured. While still in development, the team that is responsible for the sensor has also postulated that integration with a smartphone as a read-out for changes in electrical resistance would be the next step.
A great deal of excitement about the sensor stems from its immediate applicability. The sensor does not need to be inserted into meat as long as packaging is airtight, and Swager has indicated that retailers will have access to the technology in the near future. This is another addition to the exciting inventions that have huge implications for cutting down food waste and hopefully it will begin to make appearances outside the lab in the very near future.