Water Chemistry

Water Chemistry is optional, but can be a great way to really brew the best possible beers.

Many brewers will not use Brewing Salts to adjust their water, and it is not always necessary to create great beer. However, for advanaced brewers or brewers that wish to adjust their brewing water profile there is a powerful and simple to use water calculator in the Editor screen. This is hidden by default - simply select the dropdown arrow to open the Water Chemistry Calculator.

To get the best possible brews, familiarising yourself with and using brewing salts to adjust the water chemisty is a way to really get the best possible beers!

There is a great primer on using Brewing Salts here

A Brewing Salts starter kit is also available here

To use the Water Chemistry Calculator you need to know and input your Source Water Profile.

Typically your water provider will have the required information on their website.

Once you have input the correct data, remember to check the Default and the Source Water boxes.

Adjusting Water Chemistry is normally the final step when creating or amending a recipe. In part, this is because as well as the chemical makeup of the water, the grain used will also have a significant effect on the water chemistry. This is automatically calculated by the RAPT Water Chemistry Calculator.

The easiest way to use Water Chemistry is by using the built in profiles. First, you need to input and select your Deault Water Source Profile

If you do not have an accurate Source Profile then the Water Chemistry Calculator may not give accurate results.

Once the recipe is finalised, click the arrow to display the Water Chemistry Calcultor. We want to work through this step by step for the best and easiest result. While it may look quite complex, there is a lot of automation built in to make this quite easy to use.

Fermentables

You will see that the selected malts for your recipe have been automatically added to the Water Chemistry Calculator.

Each grain will also have a malt type assigned. Check that this is correct as the type of grain (base, raosted, crystal etc) can have an effect on the estimated pH level. If eny of these are not correct select the correct type of malt from the drop down menu.

Volumes

This is pre-populated based on the recipe as entered. These values can be manually amended - for example, you may decide to do a no sparge brew day.

Source Profile

The currectly selected Default Source Water Profile will be selected here. The displayed values will reflect this profile. If you wish to change the source profile click the Details button to bring up a menu of currently available Source Water Profiles.

Target Profile

To calculate the water adjustments for your recipe, click the Details button in the Target Profile section. This will bring up a list of suggested water profiles for various styles of beer. Select the target profile that best suits the current recipe.

For example, if you are brewing a Pale Alew you would select Pale Ale as your Target Profile. Not all beer styles are represented so in some cases you will need to select a Target profile that best matches your recipe.

For example, for a Begian Dubbel you might select the Balanced Target Profile or the Amber Strong Balanced profile - experimenting with different water profiles can be a great way to make subtle improvmednts or changes to your beers!

Additions

Once you have selected the Source Water Profile and the Target Water Profile it is time to calculate the salt additons for your recipe. This is performed in the Additions section.

Before we do this, you need to select which Brewing Salt additions you have to hand. The typically used Brewing Salts are listed with a toggle for Mash and a toggle for Sparge. Before calculating trhe salt additions, go down the list and select the Brewing Salts you wish to use ands whether you will modify the Mash water, the Sparge water or both. You do not need to select all the Salt Additions.

A typically Brewing Salts kit for homebrewers might include some or all of:

• Gypsum (Calcium Sulfate) CaSO4 x 2H2O

• Calcium Chloride (dihydrate) CaCl₂ x 2H₂O

• Epsom Salt (Magnesium Sulfate) MgS0₄ x 7H₂O

• Slaked Lime (Calcium Hydroxide) Ca(OH)₂

• Baking Soda (Sodium Bicarbonate) NaHCO₃

Select the salts you wish to use for brewing from the list, and toggle these on for mash and/or sparge as desired. Generally Mash would always be enabled as this is the most important water profile to adjust.

In the above example, we will only be calculating Gypsum, Calcium Chloride and Epsom Salt additions for the mash.

Once these have been selected your choices will be remembered and saved for subsequent recipes so that you do not need to toggle these every time.

Now you have your Source Water Profile, your Target Water Profile and your Additions selected, simply hit the Calculate Additions button!

The Water Chemistry Calculator will calculate the correct salt additions to best emulate the selected Target Water Profile based on the Source Water Profile and display the correct salt additions.

In this example the Source Water Profile is Reverse Osmosis (RO) water, the Target Profile is Hazy IPA. Once the calculations have been made we need to add 3.11g Gypsum, 7.77g Calcium Chloride and 3.11g Magnesium to the mash water to acheive the desired water profile.

To use this information, whe preparing the strike water for brewing carefully weigh out and add the salt additions to the strike water. It is best to do this well before adding the grains as this allows time for the chemicals to fully dissolve.

NOTE: When a Salts field is toggled n, the salt additions will be automatically calculated. For Salt Additions that are not toggled on, you can enter a valuein that field.

This value will be accounted for when the Salt Additions are calculated.

For example, you might want to add a pre-determined amount of Sodium Chloride (if brewing a Gose, for example), but still use the calculator for the other brewing salts.

Simply enter the amount of Sodium Chloride in the text box, then hit Calculate. The correct Salts will be calculated allowing for the entered quantity of Sodium Chloride

Acid Additions (Mash)

Once the Water Chemistry calculations have been performed, the Acid Additions (Mash) section of the Water Chemistry Calculator will be unlocked. Mashing in the correct pH range can help acheive the desired flavour profile and increase brewhouse efficiency through better conversion.

The ideal mash pH range for most beers is between 5.2 - 5.5pH

The calculator will account for the Water Source, the salt additions (as calculated) and also the grain bill. Ensure that the type of malt is correct in the Fermentables section of the calculator, as this will have quite an effect on the acid calculations.

The current pH adjustment will be displayed here - this is the effect on the mash pH from the Water Source Profile and the grain bill.

Below this we have the currently calculated Mash pH with a breakdown of the Mash, Sparge and Total water pH, with a breakdown of the calculations. This is the unadjusted pH of the mash

To calculate the required acid addition, choose your acid type (Lactic or Phosphoric) and set the concentration (default 88%) to match the strength of the acid.

Enter the amount of acid to be added in mLs and hit the Calculate button.

Both the change in pH and the Calculated Mash pH will change to reflect the acid addition. This can be readjusted as required - simply enter a different value and re-calculate.

Increasing pH

In most cases it will not be necessary to increase the mash pH as for most beers the mash pH will be higher than desired.

However, if the grain bill has a large amount of dark or roasted malts, then it may be necessary to use Baking Soda (Sodium Bicarbonate) NaHCO₃ to raise the pH.

To calculate how much Baking Soda is required to raise the pH level of a dark mash, then simply perform the water calculations as normal. Once this is done trhen manually enter the required amount of Baking Soda (Sodium Bicarbonate) NaHCO_{3 i}n the Additions section of the Water Chemistry Calculator. Do not toggle this as we will be entering this manually.

Once the necessary amount of Baking Soda has been added select the Calculate Additions button again. This will recalculate both the brewing salts addtions and the mash pH, adjusted by the Baking Soda addition. If necessary, change the amount of Baking Soda and recalculate until the desired pH is reached.