Viscimation is the
turbulence
In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between ...
when liquids of different viscosities mix,
particularly the formation of
vortices
In fluid dynamics, a vortex ( : vortices or vortexes) is a region in a fluid in which the flow revolves around an axis line, which may be straight or curved. Vortices form in stirred fluids, and may be observed in smoke rings, whirlpools in th ...
(also known as "viscimetric whorls") and visible separate threads of the different liquids.
The term viscimation is archaic and idiosyncratic to
whisky
Whisky or whiskey is a type of distilled alcoholic beverage made from fermented grain mash. Various grains (which may be malted) are used for different varieties, including barley, corn, rye, and wheat. Whisky is typically aged in wooden c ...
tasting; their study (or appreciation) is called viscimetry, and the capacity of a whisky to sustain viscimation (which is predominantly its alcohol percentage) is viscimetric potential or viscimetric index.
Causing viscometric whorls by adding water to liquor is colloquially called "awakening the serpent".
References
* https://web.archive.org/web/20070930102236/http://www.smws.ch/downloads/Newsletter-Xmas2004-en.PDF
Fluid dynamics
Turbulence
Vortices
Whisky
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