Mineral Additions for Kettle Top Up?

Hey folks. I'm going to be sour'ing a Stout by filling my 5 gallon glass carboy to the brim with wort and adding a couple ounces of malted grain and hold it at around 100F for 36-48 hours before boiling and adding hops.

From what I understand, it's best to reduce headspace to near zero during the lactic fermentation pre-boil. In order to do this, I have to use my 5 gallon glass carboy. This means that I will have to add top up water to account for trub loss and boil-off rate. I'll have to add roughly 1.25 gallons of water to the kettle before boiling to make sure I have the appropriate volume at the end.

When I'm using the Bru'n Water calculator, it doesn't account for top up water. Just mash and sparge water. I am using distilled water with all salts/minerals added. My concern is that if I add 1.25 gallons of distilled water to my kettle, the mineral balance now becomes off by 1.25 gallons and the finished product may not have the appropriate level of minerals for taste/mouthfeel/bitterness/malty/etc.

Am I over thinking this and it will be ok? Is 1.25 gallons negligible to effect the levels? Should I treat my top up water the same as my sparge water? As my mash water?

Any pointers would be greatly appreciated. Thanks!

In most cases, the mineral content of the water is not in the forefront of flavor perception. So having a little less mineralization won't matter much. With that said: if you are concerned about the reduction, add the minerals to make up for the dilution effect.

Well I was thinking about this early this morning and came up with this....Using the Bru'n Water sheet, it tells me how much of each to be "in profile" and I can adjust for the volume to make the 5 gallons that is going in the carboy. Adding distilled water to top up does dilute these minerals, however, the boil-off is essentially "distilling" off 1-1.25 gallons, essentially bringing me back toward the desired mineral content. Right?

mabrungard said:

In most cases, the mineral content of the water is not in the forefront of flavor perception.

Click to expand...

I understand this differently. For example certain minerals in certain quantities enhance the perception of bitterness along with other flavors. I know you don't "taste" the actual minerals, but they do affect the profile of the beer at drinking time, not just mash, right?

USMCPayne said:

Adding distilled water to top up does dilute these minerals, however, the boil-off is essentially "distilling" off 1-1.25 gallons, essentially bringing me back toward the desired mineral content. Right?

Click to expand...

Only if you are boiling off that extra water volume in addition to the normal boil off volume. That may not be a reasonable assumption in all cases. The other consideration is the reduction in gravity due to the top off water.

In any case, I look at only the starting water quality as the criterion. There are too many things like boil off rate, contributions from the malt, precipitation in the mash and boil, and yeast uptake that alter the ionic content of the finished wort. Focusing on only the starting water ionic content is probably the best way to maintain your focus on 'things you can change'.

Ah, that's another factor I hadn't accounted for. I'll have to look at BeerSmith and see what the numbers say. I'm sure it accounts for gravity decrease due to dilution with top-off.

So, what would your recommendation be? Don't sweat it? Just use whatever water I have?

The approach in the OP seems risky and elaborate. Why not just use some sauermalz in the grist or add lactic acid to the finished beer or make some sauermalz or sour mash separately in order to be sure its not spoiled and add that to the grist. Here are instructions on how to make some for a current thread

ajdelange said:

Yes and making a bit is a fun project. Take some low colored (doesn't have to be pale) malt, put it in a pot or pan and add enough water to just cover it. The pot should be nearly full so that if you put a lid on or cover with Saran wrap there isn't much air. Put in a warm place (ideally 47 °C - modern ovens will actually serve for this purpose) and let it sit for a few days. Lactic acid bacteria on the husks will go to work to ferment some of the sugars producing lactic acid. After a few days this 'sour mash' will either stink (some spoilage organism got in there) in which case throw it out or smell a bit acidic in which case things went well. Dump the grains and liquid out onto a cookie sheet (with a rim!) and toast in the oven until dry. Taste. Pretty tasty actually.

Or you can by it at your LHBS. That stuff is usually made by spraying sauergut (lactic fermented wort) onto grain and drying.

Click to expand...

If you want to use sour mash (which makes more sense here) don't do the drying step.

ajdelange said:

The approach in the OP seems risky and elaborate. Why not just use some sauermalz in the grist or add lactic acid to the finished beer or make some sauermalz or sour mash separately in order to be sure its not spoiled and add that to the grist. Here are instructions on how to make some for a current thread

If you want to use sour mash (which makes more sense here) don't do the drying step.

Click to expand...

Risky and elaborate? It's the method that many people use for "no boil" Berliner Weisse. Mash, rack to carboy, add grains, ferment for 36-48 hours, boil and add hops as usual. Your quoted method is exactly what I am doing, except I'm doing it with the whole batch. I don't see the real difference except size.

USMCPayne said:

Risky...

Click to expand...

If the grain contains a spoilage bacterium and the 'sour mash' goes rancid you have ruined the beer. If you make the sour mash separately and it goes rancid you throw it away and start again. You have not ruined the beer. Clearly you want to start the sour mash a couple of days before you brew so that when you actually do brew you have the sour mash ready to add to the main mash.

USMCPayne said:

...and elaborate? It's the method that many people use for "no boil" Berliner Weisse.

Click to expand...

Does that make it easier than adding some sauermalz (or even sour mash) to the mash?

USMCPayne said:

I don't see the real difference except size.

Click to expand...

I can point out what the differences are. If you don't see them or think them insignificant then ignore my comments.

True, there is a risk of ruining the whole batch. Something I had considered. In using your method, how much sour mash is needed to add a significant sour character to the beer?

That's a really tough question. There are so many variables and what you do depends strongly on what you are after. Do you want just that hint of tartness that one finds in Guiness or do you want something really tart? Remember that yeast are pretty good at leveling pH at the value they like. If the wort you feed them is at high pH they will try to secrete enough acid to get to the lower pH they prefer. If you feed them acidic wort they will devote less energy to acid production. Thus if you want just a hint then you really only need enough sour mash to get the overall mash pH into the right range for mashing and the yeast will do the rest. The roast barley gives that subtle hint of tartness you want. If you want something assertive then I think it might be better to wait and add sauergut at the end of the fermentation or blend some sour beer (finished beer that has aged exposed to air - i.e. by the methods used in the old days) or lactic acid with the fermented beer. I think that is something you will have to determine by experiment.

I have never done this (though I have made experimental sauermalz) as I find my stouts are tart enough for me without having to do anything like this. I can see a whole bunch of interesting experiments here though.

I'm honestly looking for that punch in the face "wow that's sour" effect. HAHA. Thats why I was planning on just sour'ing the whole batch. I've read up on some folks doing the BW beers and I think I'm gonna attempt those methods this round. I can always go buy more malt and water if I ruin it. I appreciate you taking the time to talk me through this, even if we sort of go OT from the original question.

Speaking of, do you have any recommendations for how to approach the Kettle Top Up question? Suppose I wasn't trying to sour a beer, and was simple topping up because I couldn't get the volume I needed in my MT.

The easy answer is that, assuming you have 4.5 gallons of water in the undiluted wort and increase it to 5.75 that would result in a decrease in the mineral concentrations of 1.1 dB. I'm making very bold here and assuming that since your body's response to things like light and sound level and indeed the chemical potentials of ionic species are all measured on a logarithmic scale so too would be your flavor perceptions. The dB is a logarithmic measure scaled so that 1 dB is just barely noticeable and 3 dB is noticeable. Thus, based on this reasoning, you don't need to worry. Of course you could always just increase the minerals by a factor of 5.75/4.5 and be assured that the concentrations would be the same after dilution as before.