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Topic: Chemex pH (10 msgs / 172 lines)
1) From: David Yeager
Oddball question for the chemists and Chemex fans:
I was demonstrating a Chemex to a friend the other day and was 
talking about how smooth the coffee was.  As he examined the (white) 
filter, he sniffed it and remarked, "Bicarb!"   He said that it 
smelled like bicarbonate of soda and suggested that the filters had 
be impregnated with that acid-neutralizing substance.  I told him 
that I had never heard of that and would look into it.
I Googled "Chemex" and "pH" and got a lot of references to "ALS 
Chemex Labs," but nothing about this possibility.
Has anyone else noticed this smell or characterized it this way?  My 
nose is certainly not good enough to tell one way or the other.  If 
it turned out to be true, it would certainly give a new slant on 
Chemex's slogan, "It's in the paper."
David Y

2) From: raymanowen
Easy one, David- interesting too. When "He said that it smelled like
bicarbonate of soda," it made me think. I couldn't remember how this
occasional odor neutralizer actually smells. A filter that imparts or
deletes  flavor is a bad filter.
If you dip one of the suspect filters into a cup of soda pop and see bubbles
evolve on the surface that continue when you withdraw it, you know that it
has some sort of base compound in it. As soluble as baking soda is, if any
were in the filter, I would expect it to wash out rather than just buffer
the acidity of the coffee solution.
I really don't think the theory will hold water. If the filter weren't
absolutely neutral, where's the control mechanism for the degree of
neutralization vs an unknown volume of coffee? And exactly how much bicarb
would be the right amount for the correct pH?
I suggest it would be a kindness if you keep a large supply of pre-moistened
wipes on hand- Not for filters but the hygiene of visitors, be they infants
or whatever. When I make dough for Irish soda bread loaves, nothing is
automatic. The recipe calls for a specific quantity of baking soda,
depending on the loaf size and number.
Cheers -RayO, aka Opa!
On 6/10/06, David Yeager  wrote:
"When the theme hits the bass, I dance the Jig!" - -Virgil Fox at the Mighty
Wichita WurliTzer- 1976

3) From: Ralph Rosen
Interesting thread about Chemex filters. The brown ones always seem 
to have a distinct smell. I usually run boilinh water through them 
before brewing, partly to warm the pot, but also to tame the smell a 
bit; it definitely throws off something, the water always seems to be 
ever so slightly brownish, and has that woody smell to it. I still 
love the Chemex as an occasional alternative to a vac pot, but the 
filters do worry me a bit.

4) From: Kit Anderson
The notion that Chemex filters contain Na2CO3 sounded really suspicious 
to me. So.... a little digging....
1)Sniffed a box of Arm & Hammer. There was no smell. Maybe, its just me.
2) I got out my pH meter and some pH 7 calibration water. I put a piece 
of Chemex filter in the water and left it for an hour. pH was 7. But pH 
meters aren't the most accurate things in the world.
3) Then I found the MSDS sheet. "Appearance and Odor: White crystalline 
powder with no odor."  http://www.delta-education.com/msds/Sodium_Bicarbonate.pdf4) If you mix an acid (coffee) with a base (sodium bicarb), you get a 
salt. I put a small pinch of the stuff in a cup of coffee and it tasted 
salty. So Chemex filtered coffee should taste salty and it doesn't. Not 
to me, anyway.
Runs with scissors and plays with food
Ralph Rosen wrote:

5) From: David B. Westebbe
Kit said:
Really?  How did I get the idea that a salt was made from the effect of an
acid on a metal?  
And BTW, folks, Kit is the guy who taught us BBQ fanatics more than all of
together knew about what happens when we burn wood, including, among other
things, what creosote is and how it is formed, and how to avoid it. So now
that we have him in our caffeinated grasps, we should all pump him for

6) From: miKe mcKoffee
Hmmm, does creosote form if you take coffee to third crack....?! Do I

7) From: Kit Anderson
David B. Westebbe wrote:
I made it up. Sounded believable, didn't it? :)  Is Na2CO3 a metal?
Would that be a 16 bar pump?

8) From: Kit Anderson
You'll have to ask *$s.

9) From: Brian Kamnetz
On 6/11/06, miKe mcKoffee  wrote:
Yes, otherwise known as Roastium....

10) From: raymanowen
"How did I get the idea that a salt was made from the effect of an acid on a
OK, I'll bite- how? NaOH + HCl -> NaCl + H2O.
 With Na and Cl being so reactive in the elemental state and NaCl a very
abundant salt, one wonders which one was waiting for the other to pass by...
On 6/11/06, Kit Anderson  wrote:
"When the theme hits the bass, I dance the Jig!" - -Virgil Fox at the Mighty
Wichita WurliTzer- 1976

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