From Water Into Liquor
How to read your water analysis
You've got your Analysis from your Water Board and, unless you had a good chemical education it looks pretty daunting but, in fact, we don't really need to get confused.
The analysis records how many samples were taken over the period of the analysis, the number and percent which are above the maximum concentration permitted by law (shown as PCV, the prescribed concentration value, or MAC, the maximum admissible concentration), the lowest and highest values recorded during that period, the average (mean) value, and will give the PCU value and the units in which it is measured. All of the minerals we are interested in are measured in milligrams per litre (mg/ L) which for all intents and purposes is the same as parts per million (ppm). We need to look only at a few lines in the analysis, under Parameter and the Mean Value or Concentration.
Get a sheet of paper and note down the following record:
|
Total Chlorine |
Not recorded as such in my analysis but believed to be recorded as: | |
|
Residual Disinfectant |
mg/1 |
(in my case .30) |
|
Hydrogen Ion |
pHval |
(In my case 7.9) |
|
Total Hardness as Ca |
mg/1 |
(mine is 122) |
|
Alkalinity as HCO3 |
mg/1 |
(mine is 256) |
|
Calcium as Ca |
mg/1 |
(mine is 110) |
|
Magnesium as Mg |
mg/1 |
(mine is 4.7) |
|
Sulphate as SO4 |
mg/1 |
(mine is 53) |
|
Chloride as Cl |
mg/1 |
(mine is 37) |
Now put your analysis away, you don't need it anymore.
A note of caution should be sounded here. Please do not use bottled water for brewing. It is subject to much less stringent checks than domestic water and may have many undesirable components which ccannot be removed. For example, some bottled waters have been shown to contain very high levels of bacteria, chemical pollutants or even uranium. Secondly, beware of water softeners of the type fitted into the water supply to your house. They soften water by removing calcium and magnesium and replacing them with sodium. This has two effects, the first is to add salt to your water which can make your beer unacceptably salty, and the second is to permanently solublise bicarbonates which then can't be got rid of.
First check for the level of Total Chlorine. My analysis does not list Chlorine as such but as Residual Disinfectant' . It is present in most public water supplies. It is added to water to kill off bacteria but interferes with brewing since chlorine (NOT chloride) can combine with components from both malt and hops to form medicinal tastes ("TCP-like"). We must get rid of any chlorine in our water before brewing, whether using a kit-can, full mashing or any method in between.
Getting Rid of Chlorine
The simplest water treatment of all is to remove chlorine.
|
a. |
You can use a active-carbon filter which has an anti-bacterial silver component. However these require replacement of the element or the whole filter from time to time as they obviously trap chlorine and other substances. Most homebrewers use one or other of the following methods. |
|
b. |
Aerate the water, use a shower head fitting when filling whatever you use from the tap, and leave it to stand for 24 hours uncovered, or |
|
c. |
boil it vigorously for 5 to 10 minutes, uncovered. |
This will remove chlorine and is probably the only water treatment you require if you do not mash your beers.
Chlorine may also be removed by adding sodium metabisulphite to the water. This can be in the form of Campden tablets. The recommended procedure is to add 1 tablet per gallon of water and leave to stand overnight One level teaspoon of sodium metabisulphite = 1 Camden tablet, so don't rush out to buy Camden Tablets if you don't need to. This method is imprecise and results in the addition of salt to your water. The proceeding two methods are to be preferred, i.e. aerate and leave for 24 hours or boil for 10 minutes.
Is your Water Acid or Alkaline?
