在各种烤条件下制备的脱咖啡因和普通咖啡中分析挥发性和非挥发性化合物
Hyunbeen Park1, Eunjeong Noh1, Mingyu Kim1
1Department of Food Science and Biotechnology, Dongguk University-Seoul, 32, Dongguk-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 10326, Republic of Korea.
Food chemistry
|September 24, 2023
概括
没有咖啡因的咖啡豆显示出改变的非挥发性化合物,包括较低的甘和碳水化合物,但与普通咖啡豆相比,含有更高的原酸. 关键的风味化合物,如3-乙基-2,5-二甲基pyrazine也减少了无咖啡因咖啡.
科学领域:
- 食品化学 食品化学
- 农业科学 农业科学
- 感官科学 感官科学
背景情况:
- 咖啡的质量受到咖啡豆的来源,加工和烤条件的影响.
- 脱咖啡因过程可以改变绿色咖啡豆的化学成分.
- 了解这些变化对于优化无咖啡因咖啡质量至关重要.
研究的目的:
- 调查条件对普通咖啡豆和无咖啡因咖啡豆的影响.
- 分析无咖啡因咖啡与普通咖啡的化学成分 (挥发性和非挥发性化合物).
- 确定负责普通咖啡和无咖啡因咖啡之间的风味差异的关键化合物.
主要方法:
- 来自四个来源的绿色咖啡豆 (普通咖啡和无咖啡因咖啡) 经过轻,中和深烤.
- 分析非挥发性化合物,包括三角蛋白,总碳水化合物和酸.
- 气色谱-质谱 (GC-MS) 和气味影响比率分析,以确定挥发性化合物及其对风味的贡献.
主要成果:
- 没有咖啡因的豆比普通豆显著降低甘氨酸 (25%) 和总碳水化合物 (16%),但含有较高的酸 (10-14%) (p < 0.05).
- 鉴定出的关键风味化合物包括3-乙基-2,5-二甲基pyrazine,5-甲基furfural和guaiacol.
- 与普通咖啡相比,无咖啡因咖啡中的3-乙基-2,5-二甲基酸的度降低了58%.
结论:
- 脱咖啡因显著改变了咖啡豆的非挥发性化学特征.
- 降低了关键挥发性化合物的水平,如3-乙基-2,5-二甲基酸盐,有助于脱咖啡因咖啡的风味差异.
- 这些发现为改善无咖啡因咖啡制品的质量和风味概况提供了洞察力.
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