Home Brew Forums

Home Brew Forums (http://www.homebrewtalk.com/forum.php)
-   Brew Science (http://www.homebrewtalk.com/f128/)
-   -   Sparging with distilled water (http://www.homebrewtalk.com/f128/sparging-distilled-water-204795/)

RichBenn 11-07-2010 07:32 PM

Sparging with distilled water
 
Now that I'm moved to a new house, I find my water supply is variable, from soft to hard due to mixing that goes on from three different sources. So I just bought some distilled water and have worked on the mash water only with TH's spreadsheet(thanks, BTW) to get the water where I want it.

But I only treated the mash water, mixing a little of the de-chlorinated tap water back in to get a mash and CL:SO4 ratio I am happy with.

My question is, for batch sparges, does not having certain ions in the sparge water have much of an impact on how much of the sugars are washed out, and/or astringincy?

Thanks
Rich

pjj2ba 11-08-2010 02:50 PM

The issue with sparging with distilled water is that it has no buffering capacity. The danger is that the pH might get too high and you could get some tannin extraction. However, when doing a batch sparge, there probably is still enough organic acids, etc. on the grains that is shouldn't be a problem. Now fly sparging is a different matter, and here distilled water would not be a good idea. As you wash away the organic acids, etc., the pH will rise.

ajdelange 11-08-2010 03:47 PM

Quote:

Originally Posted by pjj2ba (Post 2391050)
The issue with sparging with distilled water is that it has no buffering capacity.

True but it seems to me that's a good thing since there is nothing acidic in nominal water (the calcium/phosphate reaction is complete at this point and at normal sparge water pH carbonic content will be low and at normal sparge temperature its solubility will be reduced) but there is something basic (bicarbonate) that pulls it up. IOW there is nothing in typical water that can help but there is something that can hurt.

cookinwood 11-08-2010 10:12 PM

I had the same problem... weird smelling water in the summer, good water in the winter, I just bought a whole house filter and a good filter that takes 99.9% of all contaminants and smells out of the water. I hooked a quick connect up to my kitchen faucet with 2' of tubing on each side and have had great success, no contaminated or slow yeast and my beers are tasting pure!

RichBenn 11-09-2010 04:19 AM

Quote:

Originally Posted by cookinwood (Post 2392189)
I had the same problem... weird smelling water in the summer, good water in the winter, I just bought a whole house filter and a good filter that takes 99.9% of all contaminants and smells out of the water. I hooked a quick connect up to my kitchen faucet with 2' of tubing on each side and have had great success, no contaminated or slow yeast and my beers are tasting pure!

I have a nice filter under the sink. Water tastes great now, any time of year. But it is not a reverse osmosis unit, just a step up from a taste and odor filter that takes out 95% of chlorine. But that won't give me a known base water for adjusting. Might usually give me good beer, but I don't like not knowing where the acid is going to wind up, whether I have enough Ca, or the where the sulfate and chloride levels are. Thus making most of it distilled water to start gives me a known starting point.

Plastered_Marble 11-10-2010 06:26 AM

Water that's completely devoid of minerals and salts is not as suited for extractions as "normal" water. Your efficiency will be a bit lower if you use distilled water.

That's a bit, not a lot. For reference, you could make coffee with distilled water, ordinary tap water and water with some sugar added in advance. The difference is noticeable, but small.

ajdelange 11-10-2010 01:39 PM

I think this is a bit of stretch. When material moves from one phase to another it will do so until its chemical potential is the same in both phases. With water with some ion content the potential of the extracted material is lowered slightly as the other stuff lowers the activity coefficient and hence the chemical potential of the desired solute in the solvent phase somewhat but as most of what we are extracting is not ionized and the ion content in tap water is so low (WRT having an effect on ionic strength) I'd be surprised if the difference in efficiency of extraction were measurable (but I've been surprised before). I think any difference in taste in the experiments suggested would be because flavor contributions of the ions in the solvent. Not because more essence is extracted.

RichBenn 11-10-2010 07:39 PM

Quote:

Originally Posted by Plastered_Marble (Post 2395547)
Water that's completely devoid of minerals and salts is not as suited for extractions as "normal" water. Your efficiency will be a bit lower if you use distilled water.

That's a bit, not a lot. For reference, you could make coffee with distilled water, ordinary tap water and water with some sugar added in advance. The difference is noticeable, but small.

I just finished doing the mash two days ago, using "mostly"(75-80%) distilled water for the sparge, and adjusted distilled water for the mash.

I hit my refractometer/hydrometer numbers right on the mark, assuming the 75% extraction efficiency I usually get for IPAs. In other words, within my measurement accuracy, and allowing that it's only a sample size of one, there was no difference in efficiency. (I love it when efficiency is consistent!)

As for taste, sure, coffee tastes better with the right water. I don't know if it's quite comparable, though. I'm not using pure distilled water for the beer and never would. I was just unclear about how the salts leach out of the grains during a batch sparge, how much pH change happens, and what the effect of that is on the beer.

In my case, both the mash and "overall" water profile are in the range I wanted, and I expect a great IPA out of it.

After doing more reading about water, the Kaiser's scientific experiments, and posts by Ajdelange, I'm convinced that the spreadsheet is a nice step: an evolution, not an endpoint. It gives useful "approximations" that should get one into the ballpark for what they desire. It's worked for me (so far), and the times I've checked pH it's been very close to predicted. (I should have checked the sparge pH this time, but I was out of calibration solution.)

And I also agree that for most people with soft water, on most beers, Ajdelange's simpler set of guidelines will accomplish the same task as the spreadsheet.

SpanishCastleAle 12-02-2010 04:18 PM

In Kai's Overview of pH article he mentions that distilled water has a pH of 7 but if it is allowed to stand in air it will pick up CO2 and the pH will drop to about 6.5.

This seems like it would be desirable for sparge water. True? How long does this lowering of distilled water pH take?

ajdelange 12-02-2010 04:33 PM

Quote:

Originally Posted by SpanishCastleAle (Post 2446629)
In Kai's Overview of pH article he mentions that distilled water has a pH of 7 but if it is allowed to stand in air it will pick up CO2 and the pH will drop to about 6.5.

This seems like it would be desirable for sparge water. True? How long does this lowering of distilled water pH take?

It is not enough that the pH be lowered. The "buffer" formed must have sufficient buffering capacity and with dissolved CO2 enough does not dissolve (at normal atmospheric partial pressure of CO2). Thus the lower pH is of no benefit.

Unfortunately, the same is true of 5.2. It has insufficient buffering capacity to be effective for much of anything plus it adds substantial sodium if used in the recommended dose. It is interesting to note that there are 2 groups of people when it comes to 5.2. It seems to work well for people who don't have pH meters and not at all for those who do.

If you think you need to lower the pH of your sparge water use some phosphoric or lactic acid (both available at LHBS stores). Add only enough to bring pH down to 6 or so. pH test strips are sufficiently accurate for this application.


All times are GMT. The time now is 11:36 PM.

Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.