Humans rely on sight and smell to decide whether food has gone bad, but spoilage often begins long before either of those senses notices a problem. Researchers at the University of California think they have a solution: an electronic nose that can detect food spoilage more accurately than humans can. The electronic nose uses 16 miniature gas sensors that react to different airborne compounds. Think of them as “digital taste buds” that convert chemical reactions into electrical signals, allowing them to identify a food’s unique gas fingerprint. Scientists trained the electronic nose to recognize a variety of foods, including strawberries, blueberries, bananas, walnuts, hazelnuts, cashews, peanuts, raw chicken, milk and eggs. They also taught the device to distinguish between fresh eggs and those left at room temperature for 24 and 48 hours. More complex dishes, such as salads containing multiple ingredients, will require additional testing before the technology can move closer to real-world use. Researchers believe smart refrigerators would be a great application for this kind of technology.
