Discrimination of Arabica and Robusta in instant coffee by Fourier transform infrared spectroscopy and chemometrics

被引:159
作者
Briandet, R [1 ]
Kemsley, EK [1 ]
Wilson, RH [1 ]
机构
[1] INST FOOD RES, NORWICH LAB, NORWICH NR4 7UA, NORFOLK, ENGLAND
关键词
coffee; discrimination; infrared; spectroscopy;
D O I
10.1021/jf950305a
中图分类号
S [农业科学];
学科分类号
09 ;
摘要
Two species of coffee bean have acquired worldwide economic importance: these are, Coffea Arabica and Coffea Canephora variant Robusta. Arabica beans are valued most highly by the trade, as they are considered to have a finer flavor than Robusta. In this work, Fourier transform infrared spectroscopy is explored as a rapid alternative to wet chemical methods for authentication and quantification of coffee products. Principal component analysis (PCA) is applied to spectra of freeze-dried instant coffees, acquired by DRIFT (diffuse reflection infrared Fourier transform) and ATR (attenuated total reflection) sampling techniques, and reveals clustering according to coffee species. Linear discriminant analysis of the principal component scores yields 100% correct classifications for both training and test samples. The chemical origin of the discrimination is explored through interpretation of the PCA loadings. Partial least squares regression is applied to spectra of Arabica and Robusta blends to determine the relative content of each species. Internal cross-validation gives a correlation coefficient of 0.99 and a standard error of prediction of 1.20% (w/w), illustrating the potential of the method for industrial off-line quality control analysis.
引用
收藏
页码:170 / 174
页数:5
相关论文
共 13 条
[1]   CHARACTERIZATION OF ROASTED COFFEE BY S-HSGC AND HPLC-UV AND PRINCIPAL COMPONENT ANALYSIS [J].
BICCHI, CP ;
BINELLO, AE ;
LEGOVICH, MM ;
PELLEGRINO, GM ;
VANNI, AC .
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY, 1993, 41 (12) :2324-2328
[2]  
CLIFFORD MN, 1985, COFFEE CHEM
[3]   DIFFUSE REFLECTANCE MEASUREMENTS BY INFRARED FOURIER-TRANSFORM SPECTROMETRY [J].
FULLER, MP ;
GRIFFITHS, PR .
ANALYTICAL CHEMISTRY, 1978, 50 (13) :1906-1910
[4]  
Jolliffe I., 2002, Principal Component Analysis, V2, DOI [10.1007/b98835, DOI 10.1007/B98835, 10.1007/0-387-22440-8_13, DOI 10.1007/0-387-22440-8_13]
[5]   DISCRIMINATION BETWEEN COFFEA-ARABICA AND COFFEA-CANEPHORA VARIANT ROBUSTA BEANS USING INFRARED-SPECTROSCOPY [J].
KEMSLEY, EK ;
RUAULT, S ;
WILSON, RH .
FOOD CHEMISTRY, 1995, 54 (03) :321-326
[6]  
MABBET T, 1992, COFFEE COCOA INT, V6, P22
[7]  
Martens H., 1989, Multivariate Calibration
[8]  
Massart D. L., 1988, DATA HANDLING SCI TE, V2
[9]  
SILVETZ M, 1974, TEA COFFEE TRADE J, V146, P74
[10]  
SMITH AW, 1985, COFFEE CHEM