In principle, the primary neurons correspond to the chemical sensors of the electronic nose with different sensitivity to different odors. By chemical interaction between odor compounds and the gas selleck chem Erlotinib sensors the chemical state of the sensors is altered giving rise to electrical signals which are registered by the instrument analogue with the secondary neurones. In this way the signals from the individual sensors represent a pattern which is unique for the gas mixture measured and is interpreted by multivariate pattern recognition techniques like artificial neural network, the brain of the instrument. Samples with similar odors generally give rise to similar sensor response patterns and samples with different odors show differences Inhibitors,Modulators,Libraries Inhibitors,Modulators,Libraries in their patterns.

When the Inhibitors,Modulators,Libraries sensor patterns for a series samples are compared, differences can be correlated with the perceived sample odor.As demonstrated in a paper by Haugen and Kvaal [6], the sensor array of an electronic nose has a very large information potential and will give a unique overall pattern of the volatiles. In principle, both the electronic Inhibitors,Modulators,Libraries and the human nose operate by sensing simultaneously a high number of components giving rise to a specific response pattern. However, there are two basic differences between the human and the electronic nose that should be kept in mind. The electronic nose has both large differences in sensitivity and selectivity from the human nose. The sensors of an electronic nose respond to both odorous and odorless volatile compounds.

Taking these constraints into consideration in the choice of sensors used for these instruments it is possible to design an electronic Inhibitors,Modulators,Libraries nose with a response similar Inhibitors,Modulators,Libraries to the human nose for specific compounds. Still, the mechanisms Inhibitors,Modulators,Libraries Drug_discovery involved will be fundamentally different. In principle, the electronic nose can be applied Brefeldin_A to any product that gives off sellckchem volatiles with or without smell provided that this occurs within the sensitivity range of the sensors. As sensor technology plays a crucial role in reaching the desired analytical qualities, the following review concentrates on discussing the present status of sensor technology and statistical data analysis.

Particular reference is then made to applications of electronic nose systems selleck compound to meat.3.?Sensor Array TechnologyAn electronic nose comprises a sensor array using several ��chemosensors�� and a computer. The different types of chemosensors, especially odor sensors which have been employed within an e-nose are described in this section.A chemosensor is a device that is capable of converting a chemical quantity into an electrical signal and thus respond to the concentration of specific particles such as atoms, molecules, or ions in gases or liquids by providing an electrical signal.