Development of Electronic Nose with High Stable Sample Heater to Classify Quality Levels of Local Black Tea

Abstract

An electronic nose (e-nose) equipped with a stable temperature controller has been successfully developed. Sensor response is very influenced by the temperature of the sample. The performance of the e-nose was then evaluated to differentiate the quality levels of black tea (Q1, Q2, and Q3). The black tea samples were purchased from Tambi Tea Industry in Central Java, Indonesia. Here, the quality is based on the information from the factory. For each quality level, the measurement was repeated 31 times. Therefore, the total of measurements is 93, and only six sensors, i.e. MQ-7, TGS 813, TGS 2602, TGS 826, TGS 2620 and TGS 825 have the highest influence on the patterns. By using linear discriminant analysis (LDA), the e-nose is able to classify the quality levels of all sample almost 100%. The Q1 and Q2 are 100% predicted, while for the 31 data from Q3, total 29 data can be predicted correctly.