Comparison of chemical and fatty acid composition of green coffee bean (Coffea arabica L.) from different geographical origins

摘要

This study aimed to quantitatively screen and compare the chemical compounds including protein, lipid, sucrose, total phenolics (TPC), and total titratable acidity (TTA) along with the fatty acid profile of green coffee beans from various geographical origins (China, Indonesia, Ethiopia, Kenya, Guatemala, Honduras, Brazil, and Colombia). Meanwhile, partial least squares discriminant analysis (PLS-DA) was used to investigate whether the analyzed parameters' data can be successfully applied to differentiate the geographical origins of green coffee beans. The levels of protein, lipid, sucrose, TTA, and TPC in all samples were in the range of 13.06-15.98 g 100 g(-1), 12.88-16.29 g 100 g(-1), 7.30-11.45 g 100 g(-1), 231.43-361.21 mL 0.1 mol L-1 NaOH 100 g(-1), and 37.56-50.57 mg GAE g(-1), respectively. The fatty acid composition was dominated by C-18:2, C-16:0, C-18:1, and C-18:0. The major fatty acid group was unsaturated fatty acids (USFA), accounting for 51.66-54.28% of total fatty acids. Statistical analysis showed significant differences in the chemical and fatty acid composition of green coffee beans from eight geographical origins (P<0.05). Moreover, the PLS-DA results revealed excellent discrimination between the different geographical origins of green coffee beans, highlighting lipid, C-24:0, C-22:0, C-18:3, C-17:0, C-18:0, C-20:0, C-16:0, and protein as discriminatory features.