Electronic noses indicate when a fruit is ripe.

Electronic noses are not new, but different applications for these advanced sensor systems continue to emerge. What seems to have sparked current interest is using the noses to predict when fruit is ripe. You'd probably purchase a nose and have it customized for this or other applications.

Scientists at the University of Warwick (Electrical and Electronic Engineering Division, School of Engineering, Coventry CV4 7AL, England, U.K.) have investigated ripeness applications using bananas and apples. They employed a relatively small bench-top nose interfaced to a PC. The fruit was placed in a container over the nose's sensors. The unit determined its ripeness nondestructively.

Researchers also are conducting experiments using a prototype hand-held nose developed by Cyrano Sciences Inc. (73 N Vinedo Ave., Pasadena, CA 91107), the production version of which may be available later this year, we're told. At Warwick, research has been carried out on the use of thin- and thick-film semiconducting materials for odor sensing. Research is centered upon the use of arrays of metal oxide and conducting polymer odor sensors. The latter are of interest because their molecular structure can be engineered for a specific odor-sensing application.

A number of electronic noses have been developed by the group. There are several laboratory-based instruments, one employing an array of 12 metal oxide sensors, and another employing an array of 24 conducting polymer sensors. The conducting polymer instrument is fully automated with three separate flow-injection lines and three vessels for odor samples. Several portable instruments also have been built, including a four-element tin oxide device, a six-element tin oxide electronic nose and four 12-element polymer electronic noses.

Warwick scientists are open to collaborating with industry on the development of new odor sensors, materials and algorithms. The University of Warwick also will license some of the technology.

Further information. Julian Gardner; phone: [phone]; fax: [phone]; email: [e-mail]; URL: http://eng.warwick.ac.uk/srl. At Cyrano Sciences: Saskia Feast; phone: [phone]: fax: [phone]: email: [e-mail]; URL: http://www.cyranosciences.com.