Does gypsum and CaCl2 require heat to dissolve in water?

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rhys333

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Hey guys,
I've made the switch to using RO water, and I'm wondering if I need to heat the water to properly dissolve gypsym and CaCl2. Can I just add it to the 5 gal water jug and do the old shaka-shaka? That way everything is pre-mixed, ready for mash and sparge. Thanks in advance!
 
I add both acid and minerals to cool (70ish) RO water before heating. Usually with a good stir everything dissolves. The water gets a little turbid as the heat loads into the liquor and clears by the time I hit strike temps. I do watch for any precipitation when doing something with a lot of hardness minerals.
 
Calcium chloride is hygroscopic, and readily absorbs water, and even absorbs humidity from the air. You'll have no problem dissolving that in any temp water. Gypsum is less soluble but will still dissolve easily in your mash water. Drop in the salts while you're heating your strike water and give it a few good stirs.
 
Calcium chloride is so soluble in water that at the levels we use in brewing it doesn't matter whether the water is hot or cold. Gypsum is much less soluble than calcium chloride but even with it you will not exceed the solubility at brewing levels. Gypsum is, however, more soluble in cold water than hot. Even with cold water it can still take quite a bit of stirring to get it all to dissolve. So add your minerals to cold water and stir thoroughly. If anything settles out on the bottom of the container you did not stir enough.

An exception to all this is, of course, chalk but you won't be using any of that.
 
As I noted in #5 it can take a lot of stirring to get gypsum to dissolve in water, particularly hot water. You can't achieve that level of stirring in mash unless you are a lot stronger than I am. At least in adding it to the water you can see if there is still some undissolved and continue stirring. That you cannot do when mixing it into the grain. Thus I think you would find, if you could see the particles, that the dissolution of gypsum would not be as effective in hot mash as it would be in cold water.

An additional advantage of dissolving it in the water is that it is ready to go to work (the calcium/phytin reaction takes some time) right at strike. If you have to mix it in to the grains that takes some time and, as noted, it will not be as completely dissolved.
 
I add mine directly to my mash tun. It dissolves in there really good

Unfortunately, this has been proven to be false. Adding minerals and acids directly to the grain in the mash tun makes it very difficult to 1) make sure the minerals are dissolved and 2) distribute the ionic content evenly throughout the wort.

ALL MINERALS used in brewing (except chalk), dissolve readily in water at the concentrations we typically use in brewing. ADD ALL MINERALS AND ACIDS TO THE MASHING WATER PRIOR TO ADDING THE GRAINS AND MAKE SURE THEY ARE THOROUGHLY MIXED AND DISSOLVED. If there is still sediment in your pot after adding the minerals, you didn't mix it well enough or long enough.
 
Unfortunately, this has been proven to be false. Adding minerals and acids directly to the grain in the mash tun makes it very difficult to 1) make sure the minerals are dissolved and 2) distribute the ionic content evenly throughout the wort.

ALL MINERALS used in brewing (except chalk), dissolve readily in water at the concentrations we typically use in brewing. ADD ALL MINERALS AND ACIDS TO THE MASHING WATER PRIOR TO ADDING THE GRAINS AND MAKE SURE THEY ARE THOROUGHLY MIXED AND DISSOLVED. If there is still sediment in your pot after adding the minerals, you didn't mix it well enough or long enough.

I have not had problems. I take a ph reading before and after and hit my targets each time. I just mix the mash pretty well.
 
The benefits of dissolving it in cold water have been explained to you. You can choose to avail yourself of those benefits or keep doing things the way you have been. If it ain't broke don't fix it. Better is the enemy of good enough.
 
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