Magnesium and Adjuncts

[VikeMan]

I think it's fairly well established (or at least believed by many) that if you are building water from distilled or RO, that you don't normally need to worry about magnesium (needed for good fermentation), because your wort will get it from the grains in the mash. My question is...is the amount of Mg typically derived from the mash at a bare minumum level, and if you were going to supplement your fermentables with say, 20% table sugar, would the wort then be magnesium deficient? TIA!

---VikeMan

 

[ajdelange]

Probably not. Malt is about 0.15% magnesium by weight (IIRC). One pound of malt in 2 L water (a loose mash) would yield 340 mg/L.

 

[VikeMan]

Probably not. Malt is about 0.15% magnesium by weight (IIRC). One pound of malt in 2 L water (a loose mash) would yield 340 mg/L.

So I guess I shouldn't bother adding another 8 or 9 ppm? Thanks!