I was looking for the answer in this forum, because I thought it should be covered, so sorry if it is but I couldnt find it and this new topic is a duplicate.
The question which bothers me is how I should calculate my salt additions. I know the method of calculating particular salt addition, but the question is should I divide it by proportion for mash water and sparge water?
For example, I know that for my 20 l brew I need 30 l of water and to put 10 g of gypsum into the water, how should I do it if I am using grainfather and i am firstly pouring 19 l for mashing and after 11 addition for sparging?
Should I put 10g into the mashing water or divide it for mash and sparge water by proportion?
As you can probably see, I have never done water treatment before, so quite of trying to get the idea how to do it Maybe someone has some good references for this topic?
A member on here, mabrungard, is a water expert and has created a spreadsheet, Bru’n Water, that many on here use. It’s a great simple tool that does exactly what you’re looking for, and also does a good job of explaining what’s going on under the hood.
You should download a copy of Bru’n Water, read the water knowledge tab, and play around with it.
It really depends on your water and what you are brewing, but you can do it either way.
If you add all the gypsum to your strike water rather than dividing it between the strike and sparge water, you will have more calcium in the mash. This will lower the pH more as the calcium interacts with the malt phosphate. That may or may not be desirable for you.
Since I brew mostly pale beers with distilled water, I add all my salts to the strike water. This helps pull the pH down to the acceptable range and reduces the amount of additional acidity I would otherwise have to add. I then use distilled water with no salts for my second infusion (I haven’t been sparging recently but rather using a second infusion of boiling water to step mash) which actually pushes the pH back up a bit.
If I was brewing a darker beer and didn’t need as much calcium in the mash, I’d hold some of the salts back and add them to either the second infusion water or to the kettle during the boil.
It is a good question, since there isn’t truly a right answer.
You could add all the salts for the batch in the mashing water, add them all to the kettle after mashing, or split them between the mashing and sparging water. But there are differing impacts in each case. The good thing is that most of the ionic content that you’re targeting with your salt additions will make it into the beer. But there are definitely mashing impacts that need to be addressed and accommodated in any of the cases.
Add all to the mashing water: Most helpful when you are targeting a low ionic content in your wort, like a Pilsen water. Adding all the salts to the mashing water can help drive up the calcium content which reduces mashing pH and can increase the calcium content above 40 ppm which helps remove oxalate (beerstone potential) from the wort.
Add all to the kettle: Some think that this helps avoid ionic losses in the mash, but it doesn’t. It just delays the precipitation reactions until the wort is in the kettle. Adding all salts to the kettle can help avoid an overly low mashing pH by keeping the calcium and magnesium out of the mashing water. But this trick doesn’t help too much since the kettle wort pH will drop when those salts are added in the kettle. For most brewing, utilizing the beneficial pH lowering effect of including the calcium and magnesium in the mashing water, is preferrable and this is the reason I can’t recommend this approach in typical brewing situations.
Add proportions of salts to mashing and sparging water: This works well when your targeted calcium content is already above 40 ppm and there is little worry that your wort won’t precipitate its oxalate. This method provides some pH reduction in the mash from calcium and magnesium additions and that may reduce the amount of acid that would be needed in the mash.
For light lagers, I use/add all salts in the mash - but added to the strike water before adding the water to the grain (by underletting). Martin’s Brunwater program has a simple toggle for adding all to the strike water/mash for calculation purposes. The pH has been so consistent that I rarely check it anymore…Easy Peasy and backed by science!
One of the reasons I moved from partial mashing and sparging in a cooler with a large kettle top-up was that I couldn’t figure out how to do the water treatments (there were other reasons, too). Now I do full-volume BIAB so no worries anymore because there is no sparging. I Use Bru’nWater to calculate for the mash and that’s it.
There is one situation that I didn’t anticipate. Some brewers have systems that require them to use more water in their system than they will actually use to make wort. For example, HERMS brewers that have extra water in the system to keep the exchanger submerged.
In that case, it might be enough of a reason to not treat the water initially and add the mineral salts to the kettle in proportion to the actual water used to make the wort. I can’t recommend this approach, but this is the brewer’s choice.
Maybe someone has some good references for this topic?