| Summary: | 碩士 === 國立臺灣大學 === 園藝暨景觀學系 === 107 === Chlorogenic acids (CGA) are important bioactive compounds in green coffee beans and affect cup quality. This research examined chlorogenic acid composition of 147 green coffee samples from 2016 Taiwan Specialty Coffee Evaluation and performed correlation analysis between their processing, cultivation altitude, and cupping scores. In green coffee, 5-caffeoylquinic acid (5-CQA) and 3,5-dicaffeoylquinic acid (3,5-diCQA) account for the majority of CGA. Washed coffee displayed a lower 5-CQA concentration at 58.32 mg·g-1 dw in comparison to natural coffee''s concentration of 62.51 mg·g-1 dw. Coffee eliminated in the first round of the evaluation showed a higher 3,4-diCQA concentration at 2.06 mg·g-1 dw and a lower 5-CQA concentration at 37.11 mg·g-1 dw. Cultivation altitude correlated with several CGA groups. In natural coffee, 5-CQA concentration showed a high positive correlation with (r=0.76, P ≤ 0.001) altitude. Cupping scores also showed high positive correlations (r=0.43, P ≤ 0.001) to cultivation altitudes. Although cupping scores were not correlated to total CGA concentrations, 5-CQA and 3,4-diCQA were highly positively correlated (r=0.36, P ≤ 0.001) and highly negatively correlated (r=-0.39, P ≤ 0.001) to cupping scores respectively. By stepwise forward regression analysis, 3,4-diCQA,5-CQA and 3,5-diCQA had been included in the cupping score model. These variables were negatively, positively and negatively correlated to cupping score, respectively, and gave a combined model R2 of 0.331. Concentration of 5-CQA was positively correlated to several attributes during cupping. The most significant one was fragrance (r=0.44, P ≤ 0.001). As such, concentrations of 5-CQA and 3,4-diCQA were better cup quality indicators than total CGA concentration
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