The bubble-induced population dynamics of fermenting yeasts
The bubble-induced population dynamics of fermenting yeasts
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气泡诱导的发酵酵母群体动态
DOI：
10.1098/rsif.2020.0735
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发表时间：
2020
影响因子：
3.9
通讯作者：
Ishikawa Takuji
中科院分区：
文献类型：
--
作者：
Srivastava Atul;Kikuchi Kenji;Ishikawa Takuji
气泡诱导传输是一种普遍存在的自然和工业现象。在啤酒厂中，由于酵母厌氧发酵产生的气泡而发生这种运输。两种主要的发酵，即顶部（麦酒）和底部（储藏）发酵，在糖肉汤中显示出它们的酵母分布的差异。这种差异的原因被认为是由于酵母细胞壁的表面疏水性引起的酵母泡粘附;然而，物理机制在很大程度上仍然是一个谜。在这份报告中，通过体内实验，我们开发了一个新的理论模型，酵母分布的基础上的一般守恒定律。这项工作澄清了气泡诱导的扩散是主要的运输机制，在底部发酵的拉格啤酒，而酵母气泡粘附起着主导作用，在顶部发酵的啤酒运输，从而证实了几个世纪以来的信念，在两种发酵酵母菌群的分布差异。
Bubble-induced transport is a ubiquitous natural and industrial phenomenon. In brewery, such transport occurs due to gas bubbles generated through anaerobic fermentation by yeasts. Two major kinds of fermentation viz. top (ale) and bottom (lager) fermentation, display a difference in their yeast distributions inside a sugar broth. The reason for this difference is believed to be yeast–bubble adhesion arising due to surface hydrophobicity of the yeast cell wall; however, the physical mechanism is still largely a mystery. In this report, throughin vivoexperiments, we develop a novel theoretical model for yeast distribution based on the general conservation law. This work clarifies that bubble-induced diffusion is the dominant transport mechanism in bottom-fermentation by lagers whereas, yeast–bubble adhesion plays a leading role in transporting ales in top-fermentation, thereby corroborating the centuries-old belief regarding distribution difference in yeast population in two kinds of fermentation.