Can Your Smartphone Recognise Your Rotten Food?
Imagine this: You are starving after work. When you arrive home, you quickly grab a lump of beef that you bought three days before. It is still neatly wrapped in its packaging. You then cook it and end up without leaving leftovers given how hungry you are, but you immediately start vomiting after that. Your oral temperature is higher than 38°C. You are also experiencing frequent diarrhea.
Oh no! These are the symptoms of food poisoning. You just ate spoiled beef. That’s terrible!
Should you rely on “use by” labels?
What if I tell you that your smartphone can help preventing you from consuming rotten food without looking at “best before” labels at all? You might say, how come? It is impossible!
Let’s start with this. Personally, I don’t believe in the “use by” labels in which every food product has. Why? Because they are unreliable.
It is confusing whether “best before” stamp means that the food is entirely no longer good to be consumed or is it just because they are looked a bit less pretty compared to the brand new one? We don’t know!
Some people directly throw away a bunch of food only because they lose “best before” labels. Come on! There are a lot of people out there who are dreaming of food that you throw away. This is such a waste!
Here, I want to draw your attention to meat spoilage only. We can easily recognise rotten vegetables. Usually, they have unnatural looking colours, while it is nearly impossible to notice spoiled meat only by looking at their physical appearance.
Various factors contribute to the deteriorating of food to the point in which it is not edible to humans, i.e., internal and external factors.
Spoiled meat indicates that the meat is decaying in response to interaction with microbes (this process is known as decarboxylation of amino acids) which then release gases called ammonia and biogenic amines.
These gases are the most significant signs and the origin of the bad odour from meat decomposition. However, our nose cannot smell the gases in the very beginning when decomposition begins due to the very low concentration.
Spoiled Food Detection Technology
A collaborative work done by scientists from Nanjing University and The University of Texas reveals that a gas sensor made of an organic compound, namely Polyaniline can detect the released gases. This compound is injected into a tag/sticker based Near Field Communication (NFC) protocol.
NFC is a communication protocol which enables two electronic devices to communicate with each other. In this case, it is a communication between the gas sensor and a mobile phone.
The NFC tag will act as a “digital nose” by detecting the released gases and storing them in a microchip. If the concentration of the gases is over the preset threshold, then it will enable the smartphone to read out meat spoilage. That sounds intelligent, huh?!
What a sophisticated technology, but is it safe?
The organic compound that is used as the sensor is non-toxic. It also permitted to be used as food additives according to regulations of the United States Food and Drug Administration (FDA).
What else could be done with this sensor?
This is a very promising invention. Inspired by the concept, one can design food containers for households which automatically tells food status. Moreover, supermarkets can apply this technology to their meat storage.
If these happen, you will no longer see expired date labels in your food products.