Thursday, December 24, 2009

Squash Ball Colours And Numbers

Effervescence: The Science of Champagne


Here's an excerpt, which I invite you to savor the very interesting book on the science of champagne, the author Hervé Thalis, "From science in the kitchen," For Publishing Science / Belin (2007).



"In wine laboratory of Reims, Cédric Voisin, Gerard Liger-Belair and Philippe Jeandet showed that the growth of bubbles are primarily not by the fibers, but in them: the textile fibers are hollow, and the payment of champagne flutes, where these fibers came to stick to the walls, leaving pockets in the fibers. Computer analysis of images produced by such an experimental system where the camera is coupled to a microscope revealed that the gas diffuses through the walls probably hollow fibers.

These fibers must be regarded as sets of microfibrils, where the gas dissolved in the liquid diffused. It is enhanced by the bubbles remained trapped in the fibers, so that pockets of gas inside the fibers (it is usually a handheld fiber) grow and eventually "spilling over" fibers: a bubble detaches, leaving a gas pocket in the fiber, which can grow again and cause a bubble . All this in about five milliseconds!

How the bubble detaches Does the pocket of gas remained in the fiber? The theory is not accomplished, but a hypothesis would be played by the Rayleigh effect (named after the English physicist), that an interface such as that between the champagne gas is minimized. It is, in reverse, the same effect as that which separates a regular sheath dew deposited on a spider's web at dawn in a succession of droplets: total surface water / air is lower when the droplets are formed. Here, the surface is reduced when the bubble is formed.
Detached, the bubble finally rises to the surface. Do not forget to contemplate. The next time you will have the good fortune to enjoy the drink given to the monk Pierre Perignon, you will see that the movement is not vertically. Indeed, the movement of a bubble in the liquid disturbs the latter, which deflects the bubble following the train of bubbles from a particular fiber. On the other hand, the wall also alters the upward movement of the bubbles that form trains inclined. The mysteries, however, are not reduced. For example, tracking mounted bubbles reveals that the surfactant molecules that form the surface of the bubbles (proteins, peptides ...) are pushed down the bubbles, during the rise of these. The study is difficult, because the analysis of a few molecules at an interface defies analysis means the most modern. There is a world in a glass of champagne
. "

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