Magnesium importance in water

Bubbles

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I've read in "Big Book of Brewing" that magnesium should be in brewing water at a minimal level of 10ppm, but have also read online that mashed grains will provide an adequate level of Mg for the sake of yeast health. My source water has a level of Mg at 1ppm, so I'm wondering whether I need to add epsom salt to get the Mg level up to 10ppm or just assume that mashing will give me the Mg necessary? I ask because I've seen posts that epsom salt will create a detectable and disagreeable taste in the resulting beer, which, naturally, I'd like to avoid. Using calculators, it appears I'd have to add 2 - 3 grams of epsom salt for a 5 gallon batch of beer. It seems hard for me to imagine that this level of epsom salt addition would create a problem, but I'd just as soon not find out the hard way I was wrong.
 
I use this to help with calculations for water additions.

EZwater

adding epsom salts is defintelly recommended, but you do have to balance it with the sulfate it adds as well.
 
Remember that malt has plenty of magnesium, and so it’s never needed in the brewing water. It can be added sparingly (stay under about 25 ppm in all cases) if you want to increase the sulfate without increasing the calcium in certain beers, but it’s never actually “needed” for yeast health.
 
I never add magnesium to beer, there’s really is no need as Yooper pointed out. Water chemistry is difficult the deeper you dive into it. Thankfully, water chemistry for beer is often simpler than some people would make it. An entire book written for beer water chemistry is overkill IMHO and over emphasizes it’s overall impact on beer. Don’t get me wrong, it has an impact, but it isn’t going to make a bad beer good.

Don’t sweat it too much.
 
I never add magnesium to beer, there’s really is no need as Yooper pointed out. Water chemistry is difficult the deeper you dive into it. Thankfully, water chemistry for beer is often simpler than some people would make it. An entire book written for beer water chemistry is overkill IMHO and over emphasizes it’s overall impact on beer. Don’t get me wrong, it has an impact, but it isn’t going to make a bad beer good.


I would respectfully disagree. I have an IPA that I brew on a regular basis. The amount of gypsum added makes a huge influence on perceived bitterness
 
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Agree with @Yooper and @HighVoltageMan!

The only time you really need to concern yourself with Mg is when you have too much of it (over 30ppm). At 1ppm, you're golden.

If you're concerned about yeast health, add a bit of yeast nutrient at the end of the boil (also often not necessary).

Cheers!
 
I would respectfully disagree. I have an IPA that I brew on a regular basis. The amount of gypsum added makes a huge influence on perceived bitterness

I'm relieved to hear that most feel that adding epsom salt is not necessary -- didn't like the idea of it.

Having said that, I tend to believe that some manipulation of water chemistry can be helpful. While I'm not into IPAs, I do intend to increase sulphate and chloride concentration levels (at the correct ratios) to get the results brewers of English Ales have gotten historically. I've used the data from the chart on pages 158 -159 of the book "Water" to guide me in making the recommended water chemistry profiles. I've used the Brunwater calculator in the past, but didn't have the advantage of the table I referred to in "Water." Hopefully, I'll get better results than I did in the past -- for my English Ales, I hope I get a bit more of a sharpened bitterness, but not overwhelming. Those beers I did in the past just seemed a bit too malty/muddy, even though they were still good.
 
The recipe builder has a section where you can invoke the water calculator. Although this is mostly a trial-and-error kind of process, the ionic composition of the brewing water does influence the final beer significantly. If I know the recommended water profile I need for a recipe (there are several 'standard' profiles you can choose from as well) then I will always adjust my water to the extend possible, adding Epson salt, table salt, chalk, calcium carbonate, baking soda, lactic or phosphoric acid, and even lye. Don't fear these additions, in moderation they are like seasonings you add when cooking.

That being said, many many brewers don't add anything and still make great beer.

Water chemistry can be a complex topic, and if you're 'not sure' then doing nothing is a perfectly good option. But many brewers do regularly adjust their water chemistry to good results.

PS: ANY chemicals you add to your brew must be pure, ideally food-grade. Many packages of Epsom Salt for example sold at the grocery or pharmacy have additional stuff, like 'lavender scent', that is not OK to use. Just be aware.
 
I would respectfully disagree. I have an IPA that I brew on a regular basis. The amount of gypsum added makes a huge influence on perceived bitterness
I didn't say it has no impact, it certainly does. What I'm trying to emphasis is that too many people are intimidated by the subject or they place too importance on water over other things that make a bigger impact. Like fermentation, brewing techniques, post fermentation oxidation, etc. Water is not going to fix a poorly formulated recipe or fix a fermentation problem. It should be one of the last subjects tackled.

When in doubt, brew with soft water for lighter beers, darker beers need some hardness to keep the pH from going too low. Pay attention to the amount of chloride/sulfate added to the mash, keep calcium @ 70-150ppm, nail your mash/boil pH and that will pretty much take care of most of your water chemistry.

If your an extract brewer, just use R/O or distilled water. The people who mashed the grain took care of that for you.
 
I'm relieved to hear that most feel that adding epsom salt is not necessary -- didn't like the idea of it.

Having said that, I tend to believe that some manipulation of water chemistry can be helpful. While I'm not into IPAs, I do intend to increase sulphate and chloride concentration levels (at the correct ratios) to get the results brewers of English Ales have gotten historically. I've used the data from the chart on pages 158 -159 of the book "Water" to guide me in making the recommended water chemistry profiles. I've used the Brunwater calculator in the past, but didn't have the advantage of the table I referred to in "Water." Hopefully, I'll get better results than I did in the past -- for my English Ales, I hope I get a bit more of a sharpened bitterness, but not overwhelming. Those beers I did in the past just seemed a bit too malty/muddy, even though they were still good.
a bit more towards the bitter ratio with more gypsum will certainly do that. you just cant go crazy with it. it is supposed to enhance the bitterness the hops already have.
 
I didn't say it has no impact, it certainly does. What I'm trying to emphasis is that too many people are intimidated by the subject or they place too importance on water over other things that make a bigger impact. Like fermentation, brewing techniques, post fermentation oxidation, etc. Water is not going to fix a poorly formulated recipe or fix a fermentation problem. It should be one of the last subjects tackled.

agreed. it is a fine tune to an already good recipe and process.
When in doubt, brew with soft water for lighter beers, darker beers need some hardness to keep the pH from going too low. Pay attention to the amount of chloride/sulfate added to the mash, keep calcium @ 70-150ppm, nail your mash/boil pH and that will pretty much take care of most of your water chemistry.

If your an extract brewer, just use R/O or distilled water. The people who mashed the grain took care of that for you.

I still use RO water with all grain. blank slate to start with and I have nothing to have to compensate for later.
 
The recipe builder has a section where you can invoke the water calculator. Although this is mostly a trial-and-error kind of process, the ionic composition of the brewing water does influence the final beer significantly. If I know the recommended water profile I need for a recipe (there are several 'standard' profiles you can choose from as well) then I will always adjust my water to the extend possible, adding Epson salt, table salt, chalk, calcium carbonate, baking soda, lactic or phosphoric acid, and even lye. Don't fear these additions, in moderation they are like seasonings you add when cooking.

That being said, many many brewers don't add anything and still make great beer.

Water chemistry can be a complex topic, and if you're 'not sure' then doing nothing is a perfectly good option. But many brewers do regularly adjust their water chemistry to good results.

PS: ANY chemicals you add to your brew must be pure, ideally food-grade. Many packages of Epsom Salt for example sold at the grocery or pharmacy have additional stuff, like 'lavender scent', that is not OK to use. Just be aware.

Yes, I've been developing several recipes I've done in the past successfully using water profiles that are appropriate for their styles from the Palmer/Kaminski "Water" book table I referenced above, but more laboriously by plugging in additions that fit those profiles until all aspects of the profiles (Ca, SO4, Ch, alkalinity/bicarbonate, and RA) are within the suggested ranges as well as the SO4/Ch ratios. I can do more of this using BeerSmith 3 (which allows for RA and alkalinity) than with Brunwater where I have to do calculations, which puts it over the top in terms of amount of work for me. While there may not be a GREAT deal of difference in the quality of the resulting beer, at least I know that I've done all I could regarding my water profile and am less likely to compromise the outcome by having, for example, a SO4/Ch ratio out of whack. I have the time to do this until I get all the equipment I need (electric brewing system for step mashing when needed with Pilsner malts which I use a lot) together and tested. After a few recipes, I feel like I'm getting acclimated to the process of emulating the profiles and it becomes easier to do. So, yes, maybe work that's unnecessary, but it feels satisfying to put some of my college chemistry classes to good use.
 
Ha! I also use Palmer for water profiles. Good show!
 
If you think you want to add magnesium (epsom) to your beer, taste a grain of it first. You might change your mind.
 
Ha! I also use Palmer for water profiles. Good show!

Just to help me take the plunge, do you believe that those profiles have been beneficial to the beers you brewed using the profiles? After looking around at the issue, it seems like the most logical way to approach water chemistry. But I realize there's an art side as well. Gordon Strong seems to have a pretty simple approach as well -- using RO water with a pretty simple set of additions. I'm not sure if he's addressed the approach you (and soon, I) are taking. I'm resisting his approach since it would mean one more equipment investment and I think my source water is actually pretty good for all but light lagers (low Ca, Mg, Ch, SO4 and total alkalinity of 64). So, at most, I have to dilute 1:2 w/ RO or distilled water.
 
It really does support some styles. I once thought it wasn't necessary but have changed my mind.

I'm curious, given that there's apparently lots of Mg in mashed grains, in what styles have you used MgSO4 additions?
 
I'm curious, given that there's apparently lots of Mg in mashed grains, in what styles have you used MgSO4 additions?
Most notably, Piwo Grodziskie. I generally try to add to the profile level.
 
Just to help me take the plunge, do you believe that those profiles have been beneficial to the beers you brewed using the profiles? After looking around at the issue, it seems like the most logical way to approach water chemistry. But I realize there's an art side as well. Gordon Strong seems to have a pretty simple approach as well -- using RO water with a pretty simple set of additions. I'm not sure if he's addressed the approach you (and soon, I) are taking. I'm resisting his approach since it would mean one more equipment investment and I think my source water is actually pretty good for all but light lagers (low Ca, Mg, Ch, SO4 and total alkalinity of 64). So, at most, I have to dilute 1:2 w/ RO or distilled water.
Yes, I think my beers taste closer to what I am intending than if I were to not treat the water. My biggest investment was a Ward Labs water report, which showed my tap water is very low in just about everything - nice!

My equipment investment involved a $12 electronic scale precise* to 0.01 gram and maybe $20 on all the chemicals, probably less, so even compared to my hop spider it was quite reasonable.

*Reads to 0.01 gram, but heaven knows how accurate it is. Meh, I can't pour out 0.01 grams of anything anyway.
 
Just to help me take the plunge, do you believe that those profiles have been beneficial to the beers you brewed using the profiles? After looking around at the issue, it seems like the most logical way to approach water chemistry. But I realize there's an art side as well. Gordon Strong seems to have a pretty simple approach as well -- using RO water with a pretty simple set of additions. I'm not sure if he's addressed the approach you (and soon, I) are taking. I'm resisting his approach since it would mean one more equipment investment and I think my source water is actually pretty good for all but light lagers (low Ca, Mg, Ch, SO4 and total alkalinity of 64). So, at most, I have to dilute 1:2 w/ RO or distilled water.
I hate to admit it, but I agree with Gordon Strong’s approach to water. Mostly RO water and simple water salt additions.

The grain brings a lot of its own minerals to the beer like calcium, chlorides and magnesium. The ratio between chlorides and sulfates has been called into question due to the amount of chlorides brought by the malt, which is an unknown quantity to the brewer. It takes a rather large ratio for sulfates to make an impact. I typically use a 4/1 ratio for a German Pils to get the sulfate to dry the beer a bit and bring a more pronounced bitterness.

Water treatments can be kept simple. Blending is also a great option. Just keep in mind that water salts need to be added to help keep the waterborne calcium above 60-70ppm.
 

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