RECOGNITION OF FISH STORAGE TIME BY A METALLOPORPHYRINS-COATED QMB SENSOR ARRAY

'Electronic nose' applications have been increasing in number in recen t years. The reliability of these applications is mainly based on the selectivity properties of the sensors composing the array and on the s tability of their characteristics. In this paper an electronic nose ba sed on metalloporphyrins-coated quartz microbalance sensors is describ ed. Due to the nature of the chosen metals, the sensors are particular ly suitable to classify environments in which compounds containing don or atoms, such as mines, alcohols and sulphides, play a key role. The aroma of fish during storage is one of these environments. The array h as been applied both for classification and for identification of the degree of freshness of stored cod fish. Data on the recognition of sto rage days and continuous short time monitoring are reported and discus sed. Results of the electronic nose response are displayed by a method that is based on the parametrization of the input temporal evolution and allows an adequate representation of the evolving chemical environ ment.