Distilled water usage

[johnydrink]

Hello, can someone explain me how is supposed Distilled water to be stored and used. I mean the following: some stores around me sell distilled water in a bottle of 2 liters and buying 2L instead of 250ml is much cheaper. But on the 2L bottle is written than it will expire 48 hours after opening. So, if I want to use a PH meter for example once a week (and this requires rinsing the probe with distilled water after usage, etc ) if I open one such bottle one day, then after a week the distilled water is expired and I can not use it and as a consequence I can not use the PH meter. What do you do in such situations, how do you store and buy in a cheap way distilled water?

 

[bailey mountain brewer]

As far as I know distilled water won't expire or go bad, there's nothing in it to go bad. However contaminants could get into it, so store in a cool dark place, I think if you use it in a couple weeks as opposed to a couple days it should be fine... try not to leave the lid off when not using.. I typically pour out what I will use, put the lid back on immediately and store it. On average I use a jug per month and I feel like this is sufficient for the equipment I'm using it on, my Anton Parr easy dens is probably my most sensitive piece of equipment and it's been fine with the distilled water process I use.

 

[wallyLOZ]

IMHO, you'll be fine. I brew with distilled and my wife uses a gallon over a 2-3 week period. No ill effects here.

 

[Peebee]

Once you've had the lid off, the manufacturer can no longer assure you that the water is "distilled". Or "contains nothing at-all". Gases from the atmosphere start dissolving in the water. The most notable being Carbon Dioxide.

Not much, there's only 0.04% of the gas in the air, but there's no alkalinity in distilled water either that might subdue its effect: The Carbon Dioxide readily reacts with water to create Carbonic Acid ... the pH drops readily. About pH5.5 is attained in no time. Without going into what else might be formed, I think you can agree it's not strictly "distilled water" (contains nothing) anymore. But I think you can make up your own mind as to how much that might affect what you're doing with it? Brewing beer? ... no effect at-all wouldn't be far off the mark.

I'm sure anyone worried about such things, wouldn't be buying their distilled water from the local store.

 

[mabrungard]

Agree that distilled water will not 'expire' for brewing usage. However, there are some users that require purer water with a relatively neutral pH. An opened container would be subject to CO2 ingress along with dust and spores that would affect purity.

For brewing: ignore any expiration date!

 

[johnydrink]

So all of you tell to forgot the expiration date of distilled water for brewing purposes. I got this. But is it ok to rinse the probe of PH meter in distilled water with passed expiration date? I mean if ,for example, I aim PH accuracy of 5.75-5.76(accuracy to the second sign after the decimal point) , wouldn't using distilled water with expired date affect such accuracy?

 

[RM-MN]

So all of you tell to forgot the expiration date of distilled water for brewing purposes. I got this. But is it ok to rinse the probe of PH meter in distilled water with passed expiration date? I mean if ,for example, I aim PH accuracy of 5.75-5.76(accuracy to the second sign after the decimal point) , wouldn't using distilled water with expired date affect such accuracy?

The point of rinsing the probe in distilled water is to avoid any mineral deposits. Just because the distilled water is past its expiration period does not add any minerals.

The point of using distilled water for brewing is to start with a blank slate, no minerals in the water, then add just the mix that you want so you can mimic a particular profile and brew exactly the beer that a particular brewery produces or to create water that is better for general brewing than your local water supply. Being expired does not affect either of these goals.

 

[Peebee]

But is it ok to rinse the probe of PH meter in distilled water with passed expiration date?

It's okay to rinse the probe in distilled (or low TDS) water ... but do not soak the probe in that water! It will literally wear the probe out and hasten its demise.

I'm only beginning to appreciate the reasons myself, perhaps some others here can chip in with a proper reason? The fluid in the probe contains ions, the distilled water does not; so, the ions will migrate (osmosis) from the probe to the water it soaks in. It's this to-and-fro that the probe measures, and as the ions leave the probe becomes less sensitive, then unreliable, then fails completely. Hence probes have a finite life and can possibly be rejuvenated (but I don't think reliably so?).

But I'm not clear enough understanding the reasons to offer definitive guidance!