ELECTRONIC TONGUE has been utilized to discriminate and analyse various liquid foods and beverages - mineral water, fruit juices, soft drinks (sodas), coffee, milk, beer, wines, spirits (vodka, cognac, etc.) and edible oils. ELECTRONIC TONGUE has been also used to analyse flesh food, fruits and vegetables such as: fish, pork and beef, liver, etc., apples, oranges, onions and shallots, tomatoes and so on.
Many more applications of ELECTRONIC TONGUE for the analysis of foodstuffs are possible and foreseen.
Recognition of various sorts of coffee using ELECTRONIC TONGUE.
The brew prepared in the standard way has been utilized. Both individual sorts and commercial blends have been analysed.
ELECTRONIC TONGUE is capable to discriminate different samples of coffee, the calibration being stable for over 4 months.
ELECTRONIC TONGUE output is correlated to human sensory perception. Sensory evaluates produced by the professional taste panel have been utilized partly for calibration and validation and partly as unknown (test) samples. ELECTRONIC TONGUE has predicted the sensory scores for the test samples with a nice precision.
Open diamonds - sensory panel
Coloured triangles - ELECTRONIC TONGUE
Discrimination of sodas using ELECTRONIC TONGUE.
The system distinguishes between regular, diet and experimental samples, containing different sweeteners and additives. The performance of ELECTRONIC TONGUE is very stable and reproducible over long period of time (few months). The work performed together with the industrial partner.
The correlation between ELECTRONIC TONGUE and human sensory panel has been observed. The taste panel evaluated the degree of "dietness" of sodas along a one-dimensional scale and ELECTRONIC TONGUE can successfully predict the scores of panellists.
Recognition of mineral water samples using ELECTRONIC TONGUE.
The system can identify the water from the natural source and the same water transported in a stainless steel tank before being bottled. ELECTRONIC TONGUE can easily distinguish natural water samples from the artificially prepared fakes. The work performed according the request of the manufacturer.
The data of independent chemical analysis of the mineral water has been used for ELECTRONIC TONGUE calibration, and then the system has been used successfully to determine the content of several components in the water samples. Both recognition and quantitative analysis have been performed during the same measurement session.
Besides determination of concentration of multiple inorganic substances ELECTRONIC TONGUE can measure the content of various organic compounds in liquid media, such as: alcohols, organic acids, aldehydes, ethers, phenols and polyphenols, alkaloids, etc.
Determination of polyphenols in wine using ELECTRONIC TONGUE. The experiments with wines have been performed together with Italian colleagues (Laboratory of prof. D'Amico, University of Rome "Tor Vergata").
One of the common problems in the food analysis is a vague relationship between chemical analysis and human perception. ELECTRONIC TONGUE output is multidimensional indeed and is correlated both to the results of standard chemical analysis of food and to the scores produced by sensory panel.
Even such "understandable" parameter as acidity of wines is poorly correlated to the acidity perceived by humans. ELECTRONIC TONGUE can predict both total acidity from chemical analysis and acidity determined by tasters. In this way sensor system adds to more certain link between chemical analysis and perception of food.
ELECTRONIC TONGUE can also detect and measure concentration of different taste substances like quinine, leucine, caffeine (bitter), sodium chloride (salty), lactic, citric and other acids (sour), aspartame, ASK (sweet, sweet and bitter), glutamate (umami), and also industrial food colorants, preservatives and additives, e.g. benzoate.
Determination of intensity of bitterness induced by quinine.
Recognition of binary mixtures of taste substances. The work has been performed together with colleagues from INRA, Dijon, France.