Magnesium in brewing water question.

[Pehlman17]

Should I be concerned with having any magnesium in my water if I also plan to add yeast nutrient (Wyeast) toward the end of the boil?

I build my water from distilled and typically just use gypsum and calcium chloride for pH and flavor. I picked up some epsom salt recently because I've heard about potential benefits of a small amount of magnesium besides what little bit comes from the grist. Is there likely magnesium in the Wyeast nutrient and adding it to my water would just be redundant?

 

[AlexKay]

I’ll preface this by saying that I use Epsom salts and usually target 5-10 ppm magnesium. I think it’s probably a waste of my time, though, and an equivalent amount of gypsum would produce indistinguishable beer.

The few times I targeted significantly higher magnesium levels I felt it gave me an unpleasantly bitter/astringent taste. So don’t do that.

And I think there’s plenty of magnesium in malt for any of the yeast’s nutritional needs.

 

[MaxStout]

^^Agree.

The mash already provides more than enough Mg needed by the yeast. In Palmer & Kaminski's Water (p148), they state that yeast only need about 5ppm Mg, but typical barley wort provides around 100ppm.

 

[Pehlman17]

That’s good to hear. I’ll probably skip it on my next batch and just toss in a little yeast nutrient for insurance and see how it goes.

 

[dmtaylor]

It's too easy to use too much magnesium. It's not a very important brewing ingredient. You're better off not using it at all.

 

[BrewnWKopperKat]

I build my water from distilled

toss in a little yeast nutrient for insurance

Zinc and RO Water (link to Bru'n Water article)

 

[mabrungard]

For bittered beers, adding a magnesium salt is not a bad idea. But do recognize that it's easy to overdo magnesium in your water. Make SURE that your water supply doesn't already have a significant amount of magnesium already in it. I've heard of people adding it without knowledge of their existing water quality and they end up overdosing.

 

[RM-MN]

Since you already have purchased the epson salt and may not need or want it for your brew, you might want to use it in your garden as it can supply some nutrients to plants.

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/epsom-salt-gardening.htm

 

[cire]

Barley contains a significant amount of magnesium, largely because good quality barley requires an adequate source of magnesium to grow. Similarly, yeast requires magnesium for growth, but a good proportion of the magnesium supplied by barley is, or becomes, bound with phosphate and be deposited during the boil. I don't add magnesium to my liquor, but only because it already contains up to 40 ppm magnesium.

My advice is that if you don't wish to have magnesium in your brewing liquor, consider pitching more yeast.