Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Wanning, Hainan 571533, China.
Spice and Beverage Research Institute, Chinese Academy of Tropical Agricultural Sciences (CATAS), Wanning, Hainan 571533, China.
Food Chem. 2019 Jan 30;272:723-731. doi: 10.1016/j.foodchem.2018.08.068. Epub 2018 Aug 17.
In this study, room-temperature drying, solar drying, heat pump drying (HPD), hot-air drying, and freeze drying were applied to investigate the volatile profiles and taste properties of roasted coffee beans by using electronic nose, electronic tongue, and headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). Results indicated that the drying process markedly affected pH, total titratable acidity, total solids, and total soluble solids. Significant differences existed among all samples based on drying method; and the HPD method was superior for preserving ketones, phenols, and esters. Principal component analysis (PCA) combined with E-nose and E-tongue radar charts as well as the fingerprint of HS-SPME-GC-MS could clearly discriminate samples from different drying methods, with results obtained from hierarchical cluster analysis (the Euclidean distance is 0.75) being in agreement with those of PCA. These findings may provide a theoretical basis for the dehydration of coffee beans and other similar thermo-sensitive agricultural products.
本研究采用室温干燥、太阳能干燥、热泵干燥（HPD）、热空气干燥和冷冻干燥等方法，通过电子鼻、电子舌和顶空固相微萃取气相色谱-质谱联用（HS-SPME-GC-MS）技术研究了烘焙咖啡豆的挥发性成分和口感特性。结果表明，干燥过程显著影响了 pH 值、总可滴定酸度、总固形物和总可溶性固形物。基于干燥方法，所有样品之间存在显著差异；且 HPD 方法有利于保留酮类、酚类和酯类物质。主成分分析（PCA）结合电子鼻和电子舌雷达图以及 HS-SPME-GC-MS 的指纹图谱可以清楚地区分不同干燥方法的样品，层次聚类分析（欧氏距离为 0.75）的结果与 PCA 的结果一致。这些发现可为咖啡豆及其他类似热敏农产品的脱水提供理论依据。
