Spoiler Alert

Food spoilage refers to the process by which food deteriorates in quality and becomes unfit for consumption. It occurs due to various factors such as microbial activity, enzymatic reactions, oxidation, and physical damage. During transport and storage, food spoilage can be accelerated if proper measures are not taken to maintain optimal conditions. Factors such as temperature fluctuations, inadequate packaging, and extended travel times can all contribute to the problem.

And it is a significant problem with far-reaching consequences. According to the Food and Agriculture Organization (FAO) of the United Nations, approximately one-third of all food produced for human consumption is lost or wasted globally, with a significant portion of this being attributed to spoilage. This amounts to about 1.3 billion metric tons of food wasted each year.

This level of waste is disturbing, but there is also another area of concern — spoilage is not always detected, which can result in the development of food-borne diseases when this food is eaten. A big reason why bad food is not always noticed is that current testing processes are expensive and must be conducted in laboratory settings. This situation is not conducive to continuous monitoring of foods, from production and transportation to the retailer, to purchase by the consumer.

The consumer generally has nothing more to go by than an expiration date that is blind to circumstances involving improper storage and handling. A better testing device, which could enable inexpensive and continuous monitoring, has recently been proposed by a team led by researchers at Koç University. They have developed a battery-free, postage stamp-sized device that is completely wireless and can monitor food quality all the way from production to purchase.

The monitor leverages near-field communication both for supplying power and sending food analysis results to external devices like smartphones. It utilizes a novel capacitive measurement method, unlike existing monitors that measure things like a change in the color of food or electrical resistance. That makes this new approach robust in the face of factors that trip up traditional sensors, like changing moisture levels or varying distances between the food and sensor.

It is not certain exactly what the full range of foods that this new monitor will work with is, but it has been noted to work very well with high-protein foods like beef, chicken, and fish. A series of experiments were conducted in which the sensors were placed on these meats, then were put under differing conditions. After a period of three days, a 700% change in sensor response was observed among samples stored at room temperature. In contrast, samples stored in a freezer only saw an insignificant change in sensor readings over the same time period.

Because of the low cost, the researchers envision their monitors being packaged along with food on a large scale. This would provide food producers and transporters with a low-cost solution to ensure that their products are being handled correctly to minimize losses. It would also give retail stores the ability to continuously monitor the freshness of the food on their shelves. And perhaps most importantly, by simply using a smartphone app, consumers can ensure that their food is of high quality before consuming it and potentially risking illness. Towards this goal, the team is currently working to increase the potential for future commercialization of the sensor.