Using bottled Still Mineral Water

AHarper

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A simple question but one I think needs clarification.

Can you use bottled mineral water - straight out of the bottle - to top up the boiled wort to a required volume - before pitching the yeast in the fermenter? It will alter the OG of course but the calculator on here will solve that problem. You can then adjust for your efficiency being out from the recipe calculations.

I seem to remember reading - somewhere (but I may be mistaken) - that you should only use pre-boiled i.e. guaranteed sterile water but if you can drink the water straight out of the bottle is it not safe to use at any stage - even making a cold starter? The same goes for tap water but then you may not know what the chemical constituency is. Does it matter? Am I going mad due to the covid lockdown? Probably but don't answer that.
 
A simple question but one I think needs clarification.

Can you use bottled mineral water - straight out of the bottle - to top up the boiled wort to a required volume - before pitching the yeast in the fermenter? It will alter the OG of course but the calculator on here will solve that problem. You can then adjust for your efficiency being out from the recipe calculations.

I seem to remember reading - somewhere (but I may be mistaken) - that you should only use pre-boiled i.e. guaranteed sterile water but if you can drink the water straight out of the bottle is it not safe to use at any stage - even making a cold starter? The same goes for tap water but then you may not know what the chemical constituency is. Does it matter? Am I going mad due to the covid lockdown? Probably but don't answer that.
In general, and very general, if it's safe to drink, you can use it to dilute wort. Tap water is generally very clean. You should be able to use it. Boiling is a safety measure though, if I were going to thin my wort, I'd boil it first.
 
I don't see any concerns adding bottled water, whether it is distilled, or just spring water shouldn't matter. If your tap water is from the local water company I would not use due to chlorine/chloromine
 
When I brewed extract I always used bottled water for topping off. I never boiled it first and I never had a problem.
 
Spring water is often high in Alkalinity. It's not generally what the yeast want. What they want is an initial room temperature measured pH of 5.2. (5.1 - 5.2)
 
I have a double filter under my tap and I have used this water (no boiling, straight in the fermenter) in all of my..... 3 batches :p

My filter is antibacterial though (it has active carbon in it)
 
Mineral water has, err..., minerals, possibly a lot of them. If you're fine with that, proceed.

Bottled water in the first world is almost always completely sterile; it'd go bad in a year if it wasn't. Boiling does no harm and certainly will eliminate any possible bacterial contamination, so if not terribly inconvenient, boil it. You might consider non-mineral bottled water, made for babies and such, sold at the chemists or grocery store. Or distilled water. Lidl sells DW here for well under a dollar a gallon.

Tap water is also mostly sterile, but as mentioned chlorine & related stuff might be a problem. Small amounts of mold spores and bacteria are likely present, not a harm for drinking (our gut is remarkably tolerant) but a consideration for cold wort. Try this: Take the strainer off a faucet, like in the lavatory, and wipe it carefully with a white cloth or paper towel or cotton swab. Any black or pink or green? That indicates living stuff.
 
My first 6 or 7 batches were just with warm tap water and LME with a kilo of DME. Nothing else, they all turned out fine.

As Nosy said, it's insurance to boil.
 
All that being said, the only water I've ever used is tap water from the outside faucet. But, my all-grain process includes a boil. The water profile is so 'clean' Reverse Osmosis water doesn't make any sense here.
 
Spring water is often high in Alkalinity. It's not generally what the yeast want. What they want is an initial room temperature measured pH of 5.2. (5.1 - 5.2)
I would only comment that unless you are typing up with a massive amount of water it should not affect the pH very much.
 
I would only comment that unless you are typing up with a massive amount of water it should not affect the pH very much.
The water I would be using has a pH of 7.8 so it could be calculated out with some additional acid I guess - I need to do a spreadsheet I think... excellent, something to do before bed.
 
The water I would be using has a pH of 7.8 so it could be calculated out with some additional acid I guess - I need to do a spreadsheet I think... excellent, something to do before bed.

Alkalinity (as CaCO3) and pH are two quite different and not highly correlating things at typical water pH's (albeit that pH to Alkalinity correlation does improve dramatically as waters pH is reduced below ~pH 6). As opposed to this, Alkalinity (as CaCO3) correlates highly to the amount of HCO3- Bicarbonate ions extant on an equivalent weight correlation basis as follows.

EQ_Wt. Alkalinity (as CaCO3) = 50 g/mole
EQ_Wt. HCO3- (Bicarbonate ion) = 61 g/mole

Alkalinity (as CaCO3) mg/L = 50/61 x Bicarbonate mg/L
HCO3- ion (Bicarb) mg/L = 61/50 x Alkalinity (as CaCO3) in mg/L

When water has had ~94% of its Bicarbonate ions (or alternately, ~94% of its Alkalinity as CaCO3) removed it will be at ~5.2 pH. And when waters pH is 4.3 both Alkalinity mg/L and Bicarbonate mg/L hit zero, but the ideal pH target for Wort leading into fermentation is for the Wort pH to be 5.2 (with acceptability down to 5.0 pH here). The reason for this is that if yeast begin with a Wort at pH 5.2 the finished beer pH will fall into the ideal range of 3.9 to 4.3 pH. If beer finishes at above ~pH 4.4 bacteria can grow in it.

What is really needed is to know the Alkalinity (as CaCO3) of the mineral water in mg/L (ppm) units. Or alternately to know the Bicarb mg/L and calculate the Alkalinity mg/L. Or as another alternative, acidify the mineral water to pH 5.2 and then use this pH 5.2 water for post boil and cooling volume make-up (as well as for all water used if making extract beer).
 
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The water I would be using has a pH of 7.8 so it could be calculated out with some additional acid I guess - I need to do a spreadsheet I think... excellent, something to do before bed.

That pH might be fine, might not- depends on the bicarbonate/alkalinity level.

I wouldn’t use “mineral water”, though- as what minerals and how much of them? Some mineral water brands taste really good, but have added ions to them and wouldn’t be suitable for brewing. Ideally, you’d use reverse osmosis water or declorinated low mineralized water.
 
Did I say simple?

Bicarbonate of the water I use is 135mg/l

Silver_Is_Money said: [What is really needed is to know the alkalinity of the mineral water in mg/L (ppm) units. Or alternately to know the Bicarb mg/L and calculate the Alkalinity mg/L. Or as another alternative, acidify the mineral water to pH 5.2 and then use this pH 5.2 water for volume make-up.]

That's roughly what I was thinking about - I think! - the water I was thinking about using is the water I use to make the beer in the first place.

I plug that water's values into the calculator on here when I do the recipe - and add acid appropriately to get 5.4pH (I use acidified malt or Phosphoric Acid to do this as the calculator suggests) I hope I am doing this right here and I usually get pH near enough after the Mash. I don't often get the volumes I intended after the boil though hence my original question and the need to add water - somewhere.

What I haven't done - yet - is to take the pH after the fermentation has concluded. I'm guessing that by this time what ever pH results is it. Too late for any adjustment. So if we need to get the pH down to 5.2 then this needs to be done before we start the fermentation.
What does the boil do to the pH levels and how do we compensate for this change - if there is one.

There is a bit of the calculation missing here I think. Mash pH = 5.4, Post boil should be 5.2. What do we need to do to achieve this and where in the recipe / water calculation do we adjust for it?

I must have been doing something wrong somewhere and I want to fix it - without having to go back to University to complete that Chemistry section I wish I had concentrated more on.

I may have to change the water I use altogether - but not until I use up the 250lt I have already bought and have stored in my garage - and I don't plan on drinking it all unless it is in beer form!
 
pH drops somewhat across the boil. If you are entering the boil at pH 5.4 there is a fairly decent chance you are exiting the boil at ~5.2 pH.
 
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Water is complex but if I understand your issue, Al, you shouldn't worry. Boiling is insurance, the water is likely sanitary. The beer has already been mashed so the minerals you're adding with the water will only affect flavor and finished beer pH. Taste the mineral water and imagine those flavors in your beer. If it works, use the water! Remember the pH scale is logarithmic and your beer has buffers, resistance to pH change. If you add the mineral water and the flavor goes flat, add a bit of acid. Predicting mash pH is chemistry, what we're talking about is cooking. Add, taste, adjust.

pH of 7.8 is not very alkaline - 7.0 water is neutral. Unless you are adding a LOT of water, you won't be able to notice the movement in pH. Assuming finished beer pH of 4.2, your beer is about 2,600 times as acidic as the mineral water (pH 4.2 is 15,000x more acidic than neutral water, pH 7.8 water about 6x more alkaline than neutral). So if it doesn't adversely affect the flavor, go for it.

RDWHAHB.
 
Alkalinity and pH are two quite different and not highly correlating things at typical water pH's (albeit that pH to Alkalinity correlation does improve dramatically as waters pH is reduced below ~pH 6). As opposed to this, Alkalinity (as CaCO3) correlates highly to the amount of HCO3- Bicarbonate ions extant on an equivalent weight correlation basis as follows.

EQ_Wt. Alkalinity (as CaCO3) = 50 g/mole
EQ_Wt. HCO3- (Bicarbonate ion) = 61 g/mole

Alkalinity (as CaCO3) mg/L = 50/61 x Bicarbonate mg/L
HCO3- ion (Bicarb) mg/L = 61/50 x Alkalinity (as CaCO3) in mg/L

When water has had ~94% of its Bicarbonate ions (or alternately, ~94% of its Alkalinity as CaCO3) removed it will be at ~5.2 pH. And when waters pH is 4.3 both Alkalinity mg/L and Bicarbonate mg/L hit zero, but the ideal pH target for Wort leading into fermentation is for the Wort pH to be 5.2 (with acceptability down to 5.0 pH here). The reason for this is that if yeast begin with a Wort at pH 5.2 the finished beer pH will fall into the ideal range of 3.9 to 4.3 pH. If beer finishes at above ~pH 4.4 bacteria can grow in it.

What is really needed is to know the alkalinity of the mineral water in mg/L (ppm) units. Or alternately to know the Bicarb mg/L and calculate the Alkalinity mg/L. Or as another alternative, acidify the mineral water to pH 5.2 and then use this pH 5.2 water for post boil and cooling volume make-up (as well as for all water used if making extract beer).
So, would it be accurate to say the mixing beer at X pH, and bottled water with X pH, would not necessarily translate linearly by volume?
 
Water is complex but if I understand your issue, Al, you shouldn't worry. Boiling is insurance, the water is likely sanitary. The beer has already been mashed so the minerals you're adding with the water will only affect flavor and finished beer pH. Taste the mineral water and imagine those flavors in your beer. If it works, use the water! Remember the pH scale is logarithmic and your beer has buffers, resistance to pH change. If you add the mineral water and the flavor goes flat, add a bit of acid. Predicting mash pH is chemistry, what we're talking about is cooking. Add, taste, adjust.

pH of 7.8 is not very alkaline - 7.0 water is neutral. Unless you are adding a LOT of water, you won't be able to notice the movement in pH. Assuming finished beer pH of 4.2, your beer is about 2,600 times as acidic as the mineral water (pH 4.2 is 15,000x more acidic than neutral water, pH 7.8 water about 6x more alkaline than neutral). So if it doesn't adversely affect the flavor, go for it.

RDWHAHB.

your beer is about 2,600 times as acidic as the mineral water

You haven't tasted my beer have you?
iu


Yes I'm not talking about adding much - 3 or 4 liters at most bringing 17lt > 20lt approx.
 
So, would it be accurate to say the mixing beer at X pH, and bottled water with X pH, would not necessarily translate linearly by volume?

Waters "initial, or inherent" pH is highly irrelevant with respect to its Alkalinity (as CaCO3). My well water has a whopping 377 mg/L of Alkalinity (as CaCO3), and its pH is only 7.7. This as certified by Ward Labs. Your water might be pH 8 and have only 120 mg/L of Alkalinity (as CaCO3). The Alkalinity (as CaCO3) is the item of real concern. But by about pH 5.4 (pre-boil) it is no longer a concern.
 
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Pepsi and Coke are both about pH 2.52, and the average ale is about pH 4.1, and the average Lager is about pH 4.4.

10^-2.52/10^-4.1 ~= 38
10^-2.52/10^-4.4 ~= 76

Pepsi and Coke are about 38 times more acidic than the average ale and 76 times more acidic than the average lager.
 
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