"Magnetic Tongue" Developed to Taste Differences in Canned Tomatoes
The New Scientist article says that these researchers looked at the chemical composition of 18 different types of canned tomatoes by "examining hydrogen atoms with nuclear magnetic resonance spectroscopy." The protons of a hydrogen atom act like a magnet and can be measured by their energy or "relaxation speed." The sugars and amino acids in the tomato samples have different relaxation speeds and can "taste" different to the magnetic tongue.
Statistical analysis correlated collections of these compounds with flavours like saltiness, sweetness, and bitterness, as ranked by trained tasters. The "magnetic tongue" tastes tomato liquid practically straight from the can. Manufacturers could sample tomatoes during production with this sensor and quickly adjust their methods to create better tasting products.
Here's the article from the New Scientist that explains it in more detail. Fascinating!