An electronic tongue invented in Sweden gives the closest match yet to the subjective tastes experienced by people, claims Nordic Sensor Technologies. A liquid sample is placed in a container with three electrodesone of stainless steel, one of platinum and the other of gold and the current between them is recorded. But instead of looking at the signal after it has stabilised, the electronic tongue analyses the transient current that occurs when the power is switched on (WO 99/13325).
According to Nordic, this reveals more about the chemistry, and the taste, of the sample. The inventors claim that they can already detect the age of milk and orange juice.
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