Electronic Tongues: Sensors, Systems, Applications

Abstract

Multisensor systems for liquid analysis based on chemical sensor arrays and pattern recognition, which are now widely known as 'electronic tongues', represent one of the most rapidly emerging and exciting fields of non-classical analytics during the last decade. This chapter presents an overview of the research and development of electronic tongue systems and describes various sensors, sensor arrays, and their numerous applications. A sound basis for electronic tongues was provided by the extensive development of well-known selective sensors, especially electrochemical, and biological inspirations originating from sensory systems of mammalians. The up-to-date achievements of various scientific groups working in this field are reviewed. The performance of electronic tongues in the tasks of recognition (classification, identification, discrimination) of multicomponent media is considered. A useful option of multicomponent quantitative analysis with the help of electronic tongues is also reported. The correlation between the output of an electronic tongue and human sensory assessments of food flavor made by taste panel opens up an exciting possibility of measuring and quantifying the taste and flavor of foods. Application areas of the electronic tongue systems, including quality control of foodstuffs, clinical, industrial and environmental analysis, are surveyed. Future prospects for research and development of electronic tongues are discussed.

Nonspecific sensor arrays ("electronic tongue") for chemical analysis of liquids (IUPAC Technical Report)

“…The number of sensors in the array may vary from 4 to 40 [15]. Typically, the sensor array contains an excessive number of unit sensors, and thus is applicable for different analytical tasks.…”

“…Sensors based on various sensing principles can be employed in electronic tongues, the most widespread being potentiometric, amperometric, or optical sensors [15]. Sensing materials used in electronic tongues may also vary significantly.…”

“…Sensors made of chalcogenide glass and PVC-based polymer membranes with enhanced crosssensitivity can be incorporated into a sensor array as described in [15,16,[25][26][27][28][29] …”

“…Chalcogenide and oxide glasses and crystalline materials have been used as membranes of potentiometric sensors [2,16], and noble metals [17] have been used mostly for amperometric signal detection. Sensing materials based on plasticized organic polymers containing different active substances have been employed for both potentiometric [2,15,18] and optical sensors [19].…”

« Nez et langues électroniques » : bilan et perspectives pour les huiles alimentaires

“…La « Langue électronique », ou plus exactement un réseau d'électrodes métalliques spécifiques, a été utilisée pour les huiles de table. Bien que ce milieu ne soit pas conducteur ionique, l'ajout d'un tampon permet d'obtenir une discrimination des différentes huiles, ainsi qu'une indication de leur rancidité (figure 4) [12]. Cette technologie semble apporter des informations complémentaires intéressantes en raison d'un principe de détection (ionique) radicalement différent, et d'une mesure effectuée directement dans le produit.…”