Svarrogh said:
I have one question about water. What is the difference between hard water that I added lactic acid to adjust ph (let's say 5ml for ph5.3) of the mash and RO water which i didn't had to put lactic acid to get ph5.3?
Lets start out with a few definitions (again
)
Water hardness
This is the amount of calcium and magnesium ions in the liquor, usually combined with carbonate, but also found in conjunction with sulphate and other anions.
Alkalinity this is a measure of the amount of bicarbonate (hydrogen carbonate) ions in the liquor
Water hardness IS NOT THE SAME AS alkalinity, the confusion is caused because the water companies often report the alkalinity as if it is all derived from calcium carbonate, which is the way they report water hardness. This is further compounded by the various calculations in books and calculators on the net, that purport to derive an alkalinity figure from the hardness value. Any calculated value, without taking into account the other anions in the liquor is a pure guestimate, and cannot be considered 'adequate'
The only proper way to determine alkalinity is to measure it.
Reverse Osmosis
This is a process whereby water is purified, by passing it through a semi-permeable membrane. generally any dissolved ions in the liquor are too small to pass though the membrane so the output is almost pure water
Svarrogh said:
Let's say that Ca, Mg, Na, Cl and SO4 are the same. Only difference will be at residual alkalinity, right?
Wrong!! The concentration of everything that is dissolved in the liquor will be significantly reduced. Some ions are reduced by as much as 99.9%, others are only affected by up to 65%. So while the alkalinity will be reduced, so will the levels of calcium magnesium etc etc.
Svarrogh said:
What impact will have those 2 examples on finished beer? Thank you very much! :
Acid Treated
Will have a low alkalinity, which means less tannin harshness in the final beer. As the only thing removed is bicarbonate (replaced by lactate), there will be sufficient calcium, magnesium and trace elements present for the 'brewing processes' so the beer should ferment well, and the yeast will flocculate, you will have an effective hot break etc etc
RO
This liquor is not ideal for brewing without adding additional salts as the levels of calcium magnesium and trace elements are much to low for the brewing processes, plus although the mash should be considered to be a self buffering state, it does rely on calcium to achieve this. as there are low levels of calcium it is possible (probable) that at some stage in the brewing process the pH will crash to a lower than ideal level. Fermentation will be sluggish, the yeast will flocculate poorly, the hot and cold break will be poor, leading to a cloudy, difficult to clear beer with a very short shelf life.
