US (MA): Machine to soon 'sniff' out spoiling food
The first goal of the company is for the machines to sniff out spoiling food, says co-founder and CTO Jan Schnorr. Food spoilage can be contagious. As fruit ripens, it releases a musky gas called ethylene. When fruits are exposed to ethylene, they ripen more quickly and give off more ethylene themselves, creating a domino effect that speeds up the ripening process for every piece of fruit nearby.
C2Sense’s technology can detect ethylene even in trace amounts that a human wouldn’t be able to smell, enabling food sellers to spot ripening food before it spreads. A wholesaler might use these sensors to monitor crates of fruit and move those that are starting to ripen before they spread ethylene to every other crate in the warehouse, while a restaurant might use a handheld device to pinpoint individual pieces of fruit.
Sensors that are able to detect ethylene have been around for years, Schnorr says, but they’ve generally either been too expensive or unable to accurately detect ethylene outside the lab where they’ll be exposed to numerous other similar gases. What C2Sense has done is create an affordable sensor that’s also sensitive enough to detect low levels of the gas without setting off false positives.
The secret is a brand new material that Schnorr and his research team invented. The new material, which is cheap to synthesize, chemically reacts to ethylene. Schnorr’s team uses this material as a resistor in a tiny electrical circuit. As the number of ethylene molecules increase, the material’s conductivity changes and the electrical current changes accordingly. They can then measure the current to gauge the level of ethylene in the sensor’s vicinity. Now the team has modified the material to detect other gases, such as the amines released by meat or ammonia. Their current prototype is able to detect up to four different types of gas on a single chip.
Schnorr says the company’s goal is to make wireless sensor chips so cheap that they could be built into a product’s packaging, or incorporated into produce bags at the grocery store, without adding any noticeable cost at the register. Customers could then scan these chips with their phones to get a freshness reading.
Source: wired.com