Electronic Nose and Tongue for Herbal Products

The electronic nose is an array of gas sensors which measure the frequency changes of volatile vapors on its surfaces. The 'electronic tongue' consists of lipid polymer membrane electrodes (to mimic human tongue) for the analysis of liquid samples.

Title of project: Combined Electronic Nose and Tongue for the Verification of Herbal Products

Prof. Zhari Ismail
Prof. Bahruddin Saad
Assoc. Prof. A.R. Othman
A.K.M. Shafiqul Islam
Prof. Mohd Noor Ahmad (KUKUM)

Novelty and Inventiveness
A combination of an electronic tongue and an electronic nose dedicated for the classification of medicinal plant extracts using data fusion technique has been developed. The electronic nose consists of an array of gas sensors based on piezoelectric principles using lipids and gas chromatographic stationary phase materials of different selectivity patterns. The sensors measure the frequency changes due to adsorption of volatile vapors on its surfaces. Meanwhile, the 'electronic tongue' consists of lipid polymer membrane electrodes (to mimic human tongue) for the analysis of liquid samples. The measurement principle is based on potentiometric principles, where the voltage difference between the electrodes and the reference electrode are monitored. Data from the electronic nose and tongue were analysed separately using multivariate data analysis based on principal component analysis and information from both the sensors were extracted. The sensors containing important information are merged together to improve the performance of the combined sensors. Multivariate statistical methods such as Principal Component Analysis (PCA) is used for classifying the samples, although techniques such as Discriminant Analysis (DA), Principle Component Regression (PCR) analysis, Artificial Neural Network (ANN) could be used for the Detection, Classification and Quantification of the samples.

Usefulness and application of the instrument

The instrument is to be of particular significance for the detection of taste and smell. Possible application of the instrument could be in the
- The herbal and pharmaceutical industries to verify raw materials, intermediates and finished products at various stages of manufacturing process.
- The food industry including quality assessment in food production, control of food processing, inspection of fish, checking rancidity of edible oils, monitoring of food and beverage odor,
- The cosmetic and toiletries sectors for quality monitoring of flavors and frangances.


- the device could be fabricated as hand-held prototype
- rapid and real-time detection of product quality
- cost effective and user friendly
- less precaution and greater safety
- suitable for field application

For more information, please contact
Prof Zhari Ismail

(Contact details available to logged in journalists)

Published: 04 Oct 2006

Contact details:

Universiti Sains Malaysia 11800 Minden Penang

++604-6533888 (Main Campus), ++609-7651704/00/11(Health Campus), ++604-5937788 (Engineering Campus)
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