酵母对于咖啡豆在湿发酵过程中的粘液降解至关重要
Hosam Elhalis1, Julian Cox1, Jian Zhao1
1Food Science and Technology, School of Chemical Engineering, The University of New South Wales, Sydney, New South Wales, Australia.
Yeast (Chichester, England)
|July 19, 2023
概括
在湿发酵过程中,咖啡粘液的分解主要由内源性酶驱动,其次是酵母. 特定的酵母菌株,如Hanseniaspora uvarum和Pichia kudriavzevii显示出对受控咖啡加工的希望.
科学领域:
- 食品科学 食品科学 食品科学
- 微生物学 微生物学
- 农业科学 农业科学
背景情况:
- 咖啡桃的湿发酵需要完全去除粘液.
- 现有的关于粘结物降解的假设缺乏全面的动力学理解.
研究的目的:
- 为了阐明咖啡湿发酵过程中粘液分解的动力学.
- 确定内源性酶和微生物在粘液降解中的作用.
主要方法:
- 软质咖啡豆的湿发酵,经过7次不同的处理,持续36小时.
- 选择性抑制内源微生物,并添加乳酸或乳酸.
- 使用无添加剂的自发发酵来控制发酵.
主要成果:
- 内源性解活性在12小时内启动了粘液分解.
- 添加了pectinase和乳酸加速了降解到8小时以下.
- 酵母,特别是Hanseniaspora uvarum和Pichia kudriavzevii,对于完全的粘液降解至关重要,而细菌起到了轻微的作用.
结论:
- 粘液降解是一个两阶段的过程:最初的酶分解,然后是微生物的作用,主要是酵母.
- 汉塞尼亚斯波拉卵子和Pichia kudriavzevii被确定为有效的粘液分解的关键酵母物种.
- 这些酵母代表了优化咖啡湿发酵的潜在初始培养.
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