Found this information on another forum:
LACTIC ACID 88% : 0.1ml per litre removes 52ppm alkalinity
maximum rate of about 0.3ml per litre of water
CRS 0.5ml per litre of water will remove around 95 ppm of alkalinity.
Now you know what the alkalinity is, you need to adjust it to roughly the correct level. Sparge water should always be adjusted to a low alkalinity, about 30 ppm or less preferably, but for the mash water, the following is a very general target to aim for.
For a pale beer - 20 ppm
For an amber beer - 35 ppm
For a brown beer - 75 ppm
For a black beer - 120 ppm
Don't worry about being exact, most of the time a mash will naturally end up pretty close to where it should be but this step will give it a little push in the right direction.
To reduce alkalinity, there are various methods of doing so, however I'm only going to discuss reduction through acid addition, specifically lactic acid and CRS, because it's the simplest way and both are commonly available in most home brew stores.
Firstly lactic acid; now this can have a flavour impact on the finished beer if used in large quantities, therefore I would recommend using it only for relatively minor adjustments. I would err on the side of caution and suggest a maximum rate of about 0.3ml per litre of water, because a lactate flavour can be unpleasant in some beer styles. Lactic acid added at 0.1ml per litre will remove about 52 ppm of alkalinity.
As for CRS, it is more flavour neutral in beer and so can be used in higher quantities. Adding CRS at a rate of 0.5ml per litre of water will remove around 95 ppm of alkalinity.
When using acid to treat the water, always be sure to add it before you heat the water to strike/sparge temperature, and stir it in well to
No need to go elsewhere
- just have a read of
@strange-steve's
Beginners Guide to Water Treatment (plus links to more advanced water treatment in post #1) and the excellent further articles.
From the first one:
(...) Now you know what the alkalinity is, you need to adjust it to roughly the correct level. Sparge water should always be adjusted to a low alkalinity, about 30 ppm or less preferably, but for the mash water, the following is a very general target to aim for [see note 5 and exception 1]:
For a pale beer - 20 ppm
For an amber beer - 35 ppm
For a brown beer - 75 ppm
For a black beer - 120 ppm
Don't worry about being exact, most of the time a mash will naturally end up pretty close to where it should be but this step will give it a little push in the right direction.
To reduce alkalinity, there are various methods of doing so, however I'm only going to discuss reduction through acid addition, specifically lactic acid and CRS, because it's the simplest way and both are commonly available in most home brew stores.
Firstly lactic acid; now this can have a flavour impact on the finished beer if used in large quantities, therefore I would recommend using it only for relatively minor adjustments. I would err on the side of caution and suggest a maximum rate of about 0.3ml per litre of water, because a lactate flavour can be unpleasant in some beer styles. Lactic acid added at 0.1ml per litre will remove about 52 ppm of alkalinity.
As for CRS, it is more flavour neutral in beer and so can be used in higher quantities. Adding CRS at a rate of 0.5ml per litre of water will remove around 95 ppm of alkalinity.
When using acid to treat the water, always be sure to add it before you heat the water to strike/sparge temperature, and stir it in well to release CO2.