I vote for adding tannins to the boogeyman list

... along with hot side aeration and several other homebrew myths.

What I'm referring to is this pervasive fear that grains should never go above 170. It seems like you can't have a discussion about sparge water temps without someone solemnly throwing this into a conversation (and then crossing their heart, checking for the Devil behind them, and throwing salt over their shoulder).

Yes, I believe the experts when I hear that you get more tannin extraction above 170. But how bad are we talking here? I mean, it's not like your beer is going to turn into a dry Bordeaux.

And plenty of people will add hotter water as a substitute for mashing out with direct fire, but you can't tell me that some of those grains aren't higher than 170 during some of that.

Anyway, just thought I'd rant about something that I'm tired of reading over and over.

I accidentally let my last extract batch get over 170 while my wife was adding to my honey do list. The steeping water got to 180 or so. I quickly cooled it with cold water as soon as I saw this. Ya know what? The beer tastes like tannins pretty bad and I don't like it. Don't poo-poo them just yet.

I had no idea what they even tasted like until now. Not good IMHO.

Dude, I already added it to Revvy's Myth list.

Both for boiling AND squeezing the grain bags.

https://www.homebrewtalk.com/f39/dont-squeeze-grain-bag-21712/#post2449055
https://www.homebrewtalk.com/f39/boiled-grains-too-long-210131/#post2455565

Tannins are both good and bad. They add some great flavor and depth, but if you get too many you get a harsh astringent terrible flavor.

For the most part, unless you are getting your entire grainbed up above 175 or so, you will have minimal impact on the flavor. But if you end up boiling some shredded husks or getting the grainbed above 175, you may notice a serious astringency that can be attributed to tannin extraction.

I've had some terribly tannic beers submitted to competitions, and trust me- tannins are a real issue.

If you follow the "rules" and don't oversparge or get the entire grainbed over 175, it shouldn't be an issue in anything except the lightest beers. A big roasty stout can hide a ton of tannic flavor, but a classic American pilsner cannot.

I think it has more to do with the pH + grain temperature.

SwampassJ said:

I think it has more to do with the pH + grain temperature.

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That's EXACTLY what is its....temps alone won't do it, nor will squeezing...But if you have the right combo of ph and temp then you will get them.

Tannin extraction from over-sparging (fly) is real. The good news though, is that gelatin is great at removing tannins.

shelly_belly said:

Tannin extraction from over-sparging (fly) is real. The good news though, is that gelatin is great at removing tannins.

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But that is due to the change in PH that occurs when you over sparge.

Not a lot of benefit to going over 170 though, is there? Better rinsing of the grain bed maybe? But we're talking about fractions of percents, if that.

I say we also add oxidation and the fallacy of proper fermentation temperature to the boogeyman list. Come on, who's with me?!?!

EBloom97 said:

Not a lot of benefit to going over 170 though, is there? Better rinsing of the grain bed maybe? But we're talking about a fractions of percents, if that.

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Look at all the new brewer panic threads where the brewer's did, or boiled their grain and freaked out about it.....It's good to have information that shows them their beer is not instantly ruined by doing that, or the countless other things they are afraid of in their first few batches.

sudsmcgee said:

I accidentally let my last extract batch get over 170 while my wife was adding to my honey do list. The sweeping water got to 180 or so. I quickly cooled it with cold water as soon as I saw this. Ya know what? The beer tastes like tannins pretty bad and I don't like it. Don't poo-poo them just yet.

I had no idea what they even tasted like until now. Not good IMHO.

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What temperature does the grain get to during a decoction mash

SwampassJ said:

I think it has more to do with the pH + grain temperature.

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It's both. A little extra heat isn't a big problem but combined with a pH rising out of the desired range it is.

Hermit said:

What temperature does the grain get to during a decoction mash

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Once again, we should be talking about pH and not temperature. A thick mash is what boils- mostly grain and very little liquid. The low pH is the reason you aren't pulling out tons of tannins. BUT- there are definitely some. Again, that's why a decoction pulls out some of the grains, not all. Some tannin extraction adds flavor, depth, etc, but too much is harsh and astringent. It's a balancing act of pH and volume in the instance of a decoction!

Yooper said:

Once again, we should be talking about pH and not temperature.

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That was kind of my point to the poster. If it was only temp then decoction mash's would not be done. His temp rise should not have caused as much problem as indicated IF his water was in a good PH range.

Water chemistry was kind of the last piece of the puzzle for me, but thanks to AJ that is starting to come together for me now. If I was ambitious enough I'd run a poll on just how many of us are even paying attention to water/ph right now. Probably most learned to brew from a friend using the available water and the beer was good enough so they never went any further with it.

Hermit said:

What temperature does the grain get to during a decoction mash

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Yeah, but my ph was 8.1 because that's my city water and I was only steeping, thus tannins were extracted.

A mash is much lower ph.

sudsmcgee said:

Yeah, but my ph was 8.1 because that's my city water and I was only steeping, thus tannins were extracted.

A mash is much lower ph.

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Then why did you leave that out of the original post and blame the temperature?

Because it was the temperature that was the variable at hand. I said I steeped, no? You don't adjust ph for steeping extract kits, and city water is almost always alkaline. Therefore, for beginning extract brewers, temp will probably be the only factor that affects tannin extraction. I assumed experienced brewers would know this. Sorry....

sudsmcgee said:

I assumed experienced brewers would know this. Sorry....

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I think adults acting like adults is the real myth here.

Actually if your pH is high enough and you steep in the "recommended" amount of water it should be trivial to extract excess tannin from steeping grains.

Thanks. I did use more than the recommended amount of steeping water. See, I learned something.

https://www.homebrewtalk.com/f37/10-tips-better-extract-brewing-100861/
Here's some good recommendations for improving extract brewing, they specifically mention steeping in much less water than I've seen recommended by various merchants.

Even thin decoctions are fine depending on ph. I've done thin decoction pilseners with soft water and not had a problem. Tannins are created by multiple factors.

However it happens, tannins in beer are not good.

For instance, morebeer's extract with steeping grains instructions have you steep the grains in 2-3 gallons of water. Many of their kits have ~1.5 pounds of grain, this comes in at a ratio of 1 pound per 8 quarts of water in the worst case. If you started with soft water your grain is going to contribute very little buffering capacity.