The Electronic Tongue - Advance Instrument to Taste Food

Ofir Benjamin, Food Science , Tel Hai College, Metula, Israel

Recently there has been steady increase in the use of electronic tongue and nose for different applications in food and other disciplines.  These novel techniques found to be successful in discriminating between similar type of food products, detecting odor and taste defects, monitoring changes in flavor during process or shelf life, etc.  The mechanism behind the electronic tongue is based on voltammeter measuring principle with selective interactions between taste compounds and specific lipid membrane composition surrounding the sensor according to electrostatic or hydrophobic interactions. There are 8 different sensors following the five taste attributes, aftertaste astringency and umami richness. The interactions lead to a change in the membrane potential and a change to the charge density. The electric potential is measured in comparison with the signal reading from a reference solution containing an AgCl solution. The instrument high sensitivity and global selectivity for each taste attribute produces results that are strongly correlated with human sensory score. The combination of e-tongue and nose was applied before in conjunction with a sensory panel and was found to form an accurate evaluating method for food quality. Examples from recent research work using the electronic tongue in pomegranate juice discrimination between varieties and Tzaftit cheeses with salt reduction will be given.