Hej
Jeg surfede lidt på nettet for at finde noget info om den
vandfilterkeddel jeg havde set Magasin. Og det ser faktisk ud som om
amerikanske håndbryggere bruger den i stor udstrækning - ikke blot til
at fjerne klorforbindelser med men også til at fjerne hårdhed.
Den koster ca. 300, så det tror jeg at jeg vil prøve.
/Bo
Date: Thu, 29 Feb 1996 10:28:47 -0600
From: [EMAIL PROTECTED] (David M. Muzidal)
Subject: Brita water filter info
A few months ago I asked for information regarding using a Brita water
filter to treat brewing water. There were very few responses, and since
that time fellow R.C.B. reader Ian Smiley and I have been experimenting
with this very subject. Below is what we were able to gather about the
Brita filter from the product literature, from talking with Brita and
from actual hands-on use in our brewing sessions. We initialy bought
the Brita filters to remove chloramines from our water, but found out
that the Brita filter removes much more than that. We hope you find
this information useful!
a. The Brita filter is a combination of activated carbon and ion
exchange resins which exchanges H+ for cations and OH- for anions.
The filter contains a small amount of silver to prevent bacterial
growth.
b. The Brita filter removes sufficient water-hardness ions to render
the water very soft (at least Plano, TX and Ottawa, ON tap water),
without adding sodium.
c. The Brita filter removes up to 90% of chlorine compounds. It also
removes up to 93% of lead and copper. The Brita filter is is
certified by NSF International under the following standards:
- Standard No. 53: Lead Reduction
- Standard No. 42: Taste, Odor and Chlorine Reduction, Class I
Particulate Reduction, Class V
Bacteriostatic Effects
Copper Reduction
Zinc Reduction
d. The Brita filter is designed to filter 1/2 US gallon of water at a
time, which takes about 3-4 minutes. The manufacturer recommends
that no more than 2 US gallons of water be processed each day in
order to maintain filter efficiency. One Brita filter can process
up to 35 US gallons of tap water. The Brita filter pitcher costs
around $20.00 US and replacement filters cost around $7.00 US.
e. The comparitive pHs are as follows (all samples were measured
at 20C):
Ottawa, ON Plano, TX
i. Tap Water pH ~8.0 ~8.0
ii. Brita water pH ~5.5 ~5.2
iii. Boiled Brita water pH ~7.0 ~7.0
iv. 1 tsp CaSO4/10L Brita water pH ~5.5 NA
f. The water analyses before filtering are as follows (mg/l or ppm):
Ottawa, ON Plano, TX
Calcium (Ca) 17 30
Magnesium (Mg) 2 3
Sodium (Na) 3 9
Bicarbonates (HCO3) NA 92
Carbonates (CO3) NA 0
Sulfate (SO4) 27 27
Chloride (Cl) 5.5 12
Total Alkalinity 28 75
Noncarbonate Hardness NA 19
Total Hardness 58 94
Chlorine residue NA 2.8
pH 8.4 8.0
g. Imperical mashing experiments attest to the Brita's suitability
for brewing. The all-grain NA Pilsener batches (2-row pale malt
used), I believe, would be the most unforgiving beer style of
anomolies in the water. And, I'm satisfied that the water has
performed excellently in this capacity. - Ian
h. The Brita filter produces water that is practically ion free, at
least for the water tested, and should be treated like pure
(distilled) water. This is supported by the fact that the pH of
the Brita water rose from pH ~5.5 to pH ~7 after boiling (due to
dissolved CO2 being driven off).
All in all, I would say the Brita filter is an excellent water treatment
system for any homebrewer who has a less-than-ideal source of brewing
water and who is prepared to take pH measurements and make mineral
adjustments with various water salts. - Ian (Ottawa, ON)
The Brita filter is a low-cost, low-flow unit that produces fairly high
quality water (at least from my tap water). Partial mashes using pale
two row and Brita water resulted in a mash pH of ~4.9. I feel that the
Brita filter is best used as a supplemental water treatment system (given
the flow restrictions and ion content of the filtered water), but can be
used to treat all of the brewing water. - David (Plano, TX)
Many thanks to A.J. deLange for his chemistry help!
David Muzidal [EMAIL PROTECTED]
Ian Smiley [EMAIL PROTECTED]
