Re: Taste: Microwave Heating vs Boiling

[Andy Dougherty <doughera@LAFAYETTE.EDU>]

On Thu, 15 Feb 2001, William Beaty wrote:

> But seriously folks, it would be interesting if the organization of
> water's crystalline microstructure was affected by different heating
> methods.  The "Mpemba effect" (where hot water freezes faster than cold)
> probably involves the degree of supercooling that water will support
> before spontaneously freezing.  If a recent history of heating can affect
> later supercooling, maybe it can also affect how our taste receptors
> respond.

Superheating and spercooling are extremely sensitive to impurities, be
they dissolved metals or dissolved air bubbles.  At the temperature (and
pressure) of a nice cup of hot tea, I am unaware of any study indicating
any sort of persistent "crystalline microstructure" in liquid water.

The concentrations of impurities, however, can be very different depending
on the history of the sample preparation.

--
    Andy Dougherty              doughera@lafayette.edu
    Dept. of Physics
    Lafayette College, Easton PA 18042