Zero water jugs

My understanding is that pure water, I.e: distilled, is odourless, insipid and transparent. These are the tree basic characteristics of water. Therefore, the taste you get when drinking distilled water is actually the taste of your own mouth, rather than the minerals in it - as it has none.

Sorry if this has already been answered, 2 questions re Zero water:

• Zero water is NOT recommended for espresso machines WITHOUT remineralisation as espresso machines need some minerals to work correctly. Is this statement correct?
• As zero water removes all minerals, what quantity per litre of Bicarbonate of Soda is needed to create an alkalinity buffer and not prevent corrosion/scaling?

coffeealex I would rephrase your first point more as “coffee needs some alkalinity (and arguably other ions) to taste at its best”. Adding some buffering compound also helps with any corrosion from DI water

Many people like an alkalinity between 40 and 60 ppm (CaCO₃ equivalent), which means adding 67 to 100 mg of NaHCO₃ for every litre of DI water. That will be ample to prevent corrosion; scaling will depend on whether you also add Calcium and/or Magnesium compounds to the water. If you don’t… no scale.

CoyoteOldMan

I think eventually I will go down your route of making a saline solution, and then adding it to zero water. This will make things easier in practical terms. Just a little confused at what is the difference between adding bicarbonate of soda or potassium bicarbonate?

coffeealex - I tried both and I can’t taste the difference. The reason behind is that coffee already contains potassium, so adding a bit more should not distort anything.

coffeealex In addition to MediumRoastSteam reply, two ‘practical’ differences:

1. Sodium bicarbonate is commonly available in supermarkets; potassium is easy to find, but not as easy. Both are very cheap.
2. If you use potassium, then instead of 67 - 100 mg/l you need to use 80 - 120 mg/l to get 40 - 60 KH

CoyoteOldMan Thanks. I take it 40- 60 KH is the generally accepted target levels to aim for. Does adding either sodium bicarbonate or potassium bicarbonate increase the GH level? Sorry if it sounds a stupid question. I am assuming no as magnesium or calcium carbonate do this.

coffeealex Correct. “Permanent” or General Hardness requires Ca or Mg (or other divalent ions, but they don’t scale - or at least not as easily) https://en.wikipedia.org/wiki/DGH

SurreyAlan I’m conversant with mm cm m etc and even gms and kilos but would 100mgs be 0.1 gm

You’ve got it spot on. 👍😊

I remineralise zero water with 64mg of sodium bicarbonate / litre of Zero Water.

I make up 5 litre batches at a time in an old Tesco Asbeck bottle. 320mg sodium bicarbonate to 5 litres. Works well as an easy recipe and tastes good

SurreyAlan what machine do you have and what did you empty?

SurreyAlan along with lots of back flushing and just running it through the head so while there’s bound to be some tesco still there it must be very diluted.

Backflushing will do nothing. The water gets pumped, hits the expansion valve and goes back to the tank :-) - If you want to recycle the brew boiler, then just draw water from the group. 👍

Comes out in the drip tray on mine,?

If it’s a HX there’s no need to empty the boiler. If you’ve got 100mg/l Sodium bicarb then you’ve increased the alkalinity significantly over ashbeck.

CoyoteOldMan If you use potassium, then instead of 67 - 100 mg/l you need to use 80 - 120 mg/l to get 40 - 60 KH

I have ordered some scales and potassium bicarbonate. I am going to use zero water for the time being and then remineralise it with KHCO₃.~

Could I please check the two formulas. the one above is :

80-120mgl = 0.08 - 0.12 grammes per litre of zero water

There is also a bulk formula you mentioned in the past where you add 20ml of it to I think 5 litres? Could you just remind me what that is please of potassium bicarbonate?

Also does it matter that much whether you put 80mgl or 120 mgl or anything in between. I was going to use 100mgl per litre of zero water to keep it simple and easy to remember

coffeealex - the more you put in, the more alkalinity you’ll have. In the cup, it will mute acidity. 100mg/L is what I do. Keep it nice and simple indeed.