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Water dilution for mash only


Master Brewer
May 21, 2016
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Hi Brad

Currently, the water tab seems to calculate the additions on the assumption that mash and sparge water base is the same.  A user cannot indicate where the base water is used.

For example, I usually dilute my tap water with distilled water for the mash only.  This means I can get my mash adjustments right, while reducing costs by needing to buy less distilled water (it may be cheap, but it is still an avoidable cost).  I then just use the tap water (acid addition only) for sparge and add the extra salts to the boil.

This cannot be done in BS3.  The water entered is treated as though the user collects the total volume, then splits it into mash and sparge water.

Although the flavour contribution of the salts depend on the final concentration, using a different process to the way that BS3 requires it will affect pH estimations - which is one of the major purposes of salt additions

I tried just setting the volume of water to be the same as my mash water, but BS3 still wants sparge salt additions, and then calculates the water profile based on the smaller, diluted mash volume only (ie, the adj sparge water profile is also diluted, and therefore the total water profile is out).

Is it possible to direct the water additions to be either mash or sparge?  In the current beer that I'm doing, it would be 4.4L distilled (mash), 13.2L tap (mash) and 15.9L tap (sparge)

Also, is it possible to direct the salt additions to all be in the mash?  I can see a workaround by getting the calculations, then editing the mash additions to be equal to the total and deleting the sparge additions.  However, with a tool as powerful as BS3, that seems like a very manual process