deionised water?

[evilhorse]

We have a scource of deionised water.


If I were to brew a light pale ale (97% pale + 1.5% crystal and 1.5% melanoidin) with bittering aimed around 30-32 IBU without making salt adds to the water.

What would my mash ph be in the range of?
Would there be consequences for fermentation in terms of yeast nutrition?
Any further implications?
How would the bitterness taste?

 

[Beerrific]

Let's assume 5 SRM. According to Palmer, you needs a RA between -61 and -2 for that color. With no minerals, that is very close.

However, calcium is necessary for proper starch conversion and yeast health. While there is some Ca in the malt, you really would be doing your beer a disservice by using water with 0 Ca, IMO. Add something back to target 50-100ppm Ca. Yeast need cations (namely Ca and Mg) to bind and flocculation. Leaving them out could give you issues will clarity.

The ratio of SO4 to Cl can change the malty/bitter balance. While equal make it balanced, I am not sure what 0 of both would do.

All in all, I would recommend reading Ch. 15 of How to Brew and add back some CaCl, gypsum, epsom, etc. and properly build the water. It is really not that hard.
The ratio