On 5/10/2016 11:26 AM, Brooklyn1 wrote:
> Helpful person wrote:
>
>> It seems that with all the rhetoric no one has properly described how a percolator works.
>> Simply put, there is a tube containing hot water with a heater at the bottom. The heater boils
>> the water at the bottom of the tube. The steam produced then forces the water above it up the tube
>
> No steam is produced, It's not a sealed pressurized vessel, water
> vapor is produced. The boiling water is driven up the tube by
> nucleation... water boils and forms bubbles which rise, same as with
> any pot of boiling water.
>
>> So, not all the water in the tube is boiled, just a small amount at the bottom of the tube.
>> Hence some of the coffee is boiled during this process (what percentage I don't know).
>
> All of the water is boiled, all of the coffee is boiled. Heat rises,
> normal people would agree. At the very upper surface of boiling water
> some thin layer of steam may be produced, but there are other factors
> such as altitude, but regardless, the upper surface of boiling water
> is hottest. That curved plate at the bottom of the tube is for
> capturing as many rising bubbles as possible, it's the rising bubbles
> that push water up the tube, not steam.
> https://en.wikipedia.org/wiki/Boiling
> Perculators have a small clear glass knob attached to the lid, by
> observing from just prior to perculation one can readily see how the
> liquid in the pot is pushed to the top of the tube. Very quickly the
> clear water turns dark brown, proving the coffee is boiling.
>

Once again, you don't know how to properly use a coffee percolator.
Maybe that is why drip became so popular - you are no doubt not the only
one who misunderstands how to use a percolator.