The Cluster Analysis of Indonesian Coffee at Two Different Brewing Temperature Using FTIR-ATR (Fourier Transform Infrared –Attenuated Total Reflectance) Method Coupled with Chemometrics

Abstract

Coffees is an agricultural commodity that widely cultured at different region in Indonesia. From all Indonesian coffees, the best known coffee are from Aceh Gayo, Flores, Kintamani, Mandheling, Papua, Sidikalang, Toraja, Kerinci and Lampung. Those coffees have characteristic flavor that can only distinguish by the expert coffee taster. This study attempts to classify nine types of Indonesian coffee, therefore the different of those coffees tastes were studied from chemical aspect. For such purposes, the Fourier Transform Infra Red (FTIR) combined with chemometrics was used. In this case, FTIR was used to classify the coffees from various regions in Indonesia. The classification was conducted to the filtrate and residue of nine Indonesian coffees that was brewed at two different temperatures. The coffees samples studied were taken from nine regions in Indonesia, namely Aceh Gayo, Flores, Kintamani, Mandheling, Papua, Sidikalang, Toraja, Kerinci and Lampung. The chemometrics model used was principals component analysis (PCA) and cluster analysis (CA). From this study, the classification and similarities among the coffees that were brewed at two different temperatures can be known.