该研究采用定量描述分析(quantitative descriptive analysis, QDA)结合主成分分析(principal components analysis, PCA)对不同温度杀青制得的样品进行香气感官品质评价,运用气相色谱质谱联用技术(gas chromatography-mass spectrometry, GC-MS)对样品挥发性化合物进行检测,并计算化合物气味活性值(odor activity value, OAV)以比较不同杀青温度对绿茶香型形成的影响。结果显示,与各香气属性相关,阈值较低的化合物是绿茶香型差异的关键如芳樟醇、香叶醇、β-环柠檬醛等;270、320、370 ℃杀青温度制得样品分别呈现明显的青气,甜香,清香和花香。不同杀青温度可通过影响挥发性化合物组成和相对含量以实现不同香型绿茶的加工。
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