|
What is the best water for Coffee?
Well, that's a good question! After visiting
with many coffee people, I have gathered the following as a basis for
recommending the "perfect water" for coffee.
- All oxidants removed. (Chlorine or other
such sanitizers".)
- All organics removed. (You know, dead
fish, tadpoles, THM's, insecticides, pesticides, etc)
- TDS (total dissolved solids) from 60
to 100 ppm (parts per million)
- Hardness of about 3-4 grains per gallon.
(51.3 to 68.4 ppm)
- Low sodium water, i.e., less than 10
mg/L.
- pH depends on the Bean you are using,
plus the method of extraction.
- Iron, Manganese and copper gone, or
less than 0.02 ppm.
What is the best way to get this
type of water?
There is no single answer for this question,
however, if we assume you are getting your water from a municipal supply,
we *assume* the Iron and Manganese problems are taken care of by the city
plant. (Some towns may not solve these problems -- you be the judge!)
Copper *may* come from the supply itself, or, if the water is aggressive
enough, it may actually be picked off the copper plumbing in your house
as it sits overnight in the pipes. (Lead can also be leached out of the
older "sweat" joints that may have used solder that contained lead.) It
is best to "clear the pipes" the first thing in the morning before using
any water for ingestion. Simply run enough water to clear your pipes of
the 'overnight' standing water that *may* have picked up the harmful metals
from your pipes -- use it to water your houseplants. If we use a good,
properly sized carbon filter, we will substantially reduce the organics
and oxidants in the water, as well as remove most of the particulates.
However, we still have TDS and Hardness to worry about. If we soften the
water, we do not reduce the TDS, we simply *exchange* the hardness minerals
for Sodium -- which we don't want for coffee! The best answer (usually)
is the reverse osmosis system. This *system* usually has a particulate
and carbon filter (organics, oxidants and particulates are reduced); and
a membrane (reduces the TDS by about 90% -- including hardness, sodium
and others as well); all linked together in one flow path.
We can greatly improve the coffee by using any one of the above mentioned
methods, but if we combine them, we get, for all practical purposes, the
*best* water for your coffee! Rule of thumb: With an RO System, whatever
impurities were in the water are typically reduced by 90% or more, leaving
only water behind, which is what we really wanted, anyway!
How much sodium does Ion-Exchange
add to my water?
For every grain of hardness in your water,
7.5 mg of Sodium will be *added* to each quart of water by the ion-exchange
method. If you have water that is 10 grains per gallon hard; you will
add 75.0 mg of Sodium per quart of water softened by ion-exchange. To
put that in perspective, one 8-oz glass of milk contains 120 mg of Sodium,
one slice of white bread contains 114 mg of Sodium. You must also remember
that there is *probably* Sodium in the raw water, too. If your city supply
treats your water by a "hardness reduction" treatment plant, you can be
sure that the Sodium level in your water has increased as a result --
how much? Call your plant operator and ask -- it is information free to
the public.
[ Back to Table
of Contents ]
|
Filtration