Hey brewers, I just found out that I officially suck at decoction mashing. I brewed a hefeweizen last weekend and I decided to do a decoction to mash out. I was reading that you can extract more melanoidans and achieve a maltier character if you do a decoction mash out. I pulled about one third of the thickest part of the mash with a strainer. I gradually heated the decocted portion to 212 degrees and boiled for 15 min. I poured it back into the mash tun but it only heated the mash to 158. This isn’t hot enough to stop the enzymatic activity.
My question is how thick should the decocted portion be? I feel like when its too thick it doesn’t retain enough temperature. Any tips on decoction thickness would be great. Thanks
I use a large strainer to pull the decoction. I let it drain most of the liquid but you’ll need some liquid or the decoction will just burn. If you don’t have enough thermal mass to heat the mash to mashout temp then supplement a small amount of additional boiling water to get the temp up.
In short the main body of the mash was too thin so the part you pulled out simply didn’t have enough thermal mass to raise the temperature to that desired. I used to have that problem with every decoction step until I learned that a decoction mash has to be much stiffer than I thought. Gregory J. Noonan’s “New Brewing Lager Beer” recommends doughing in with between 24 to 40 ounces water per pound of grain with the larger quantity being for larger, mechanized system. So we’re talking less than one quart per pound. And yes, boiling water infusions are allowed, but the mash still will be much stiffer than its single-infusion or step mash cousins at every stage.
If you pull a decoction to mash out you want to pull liquid only otherwise the boiling of the grain will release additional starches that will require mashing.
Also, the higher the temperature of the mash, the more boiling liquid you will need to raise it. The closer it is to boiling, the larger the decoction. Usually the last (mash out) decoction is mostly liquid and much more than the mass of lower temp decoctions.
Anyway, it doesn’t matter much whether the enzymes were deactivated because they were most likely finished working by the end of the mash and I understand that raising the temp to mash out doesn’t make much difference in efficiency.
Thanks guys, I think next time I do a decoction mash out ill take a really thin portion to boil. I feel like that was my biggest problem. Though I was wondering if any grain husks get into the thin decoction boil would that leech out tannins? This is one question that is bugging me seeing as this is the main reason why we lauter, to keep out grain husks from the boil. Any input on that?
The difference in tannin extraction relies on pH. As you lauter, the pH will rise to a point that you want to stop, but during the mash the pH will deter tannin extraction.
+1 on this, with a shorter protein rest. and use soft water especially if you’re doing a Czech Pils. If you are coming up light on your rest temps, pull a little more next time. I usually fall short a couple degrees and apply direct heat (RIMS), but you just need to have some boiling water at the ready. IMO, decoction is well worth the time and effort akin to fly fishing versus “bait n wait”.
I do decoction mashing fairly often, and just used it yesterday for a Maibock. I think it’s a useful (though certainly not necessary) technique that is often discouraged by myth and misconceptions. I use the technique because of its historic use for certain beer styles as much as I do for its results.
If it’s something you’d like to learn about, I’d suggest you check out this section of Kai Troester’s Wiki site Decoction Mashing - German brewing and more Make sure to scroll down the page and watch the videos. Kai does an excellent job of describing the history, process and some of the science of decoction mashing. His videos really do a great job of illustrating the process.
Once you get used to the process, it’s really not very difficult. You can find decoction volume calculators like this one http://www.quaff.org/cyberbrau/DecoctionCalculator.htm to help. I also always pull about 10% more mash for the decoction than calculated in case the main mash drops a few degrees while the decoction is going on. If you end up with too much boiling decoction, you can always let it cool before adding it back to the main mash. As well, you’ll have boiloff as you do the decoction, so I add some water to the decoction to compensate for that. And, as others have mentioned, have some boiling water handy in case you need to add a little extra heat to boost to your targeted step or mash-out temperature.
Congratulations! You made beer. By boiling the decoction, you likely accomplished your goal of getting those pesky melanoidens.
My first decoction, I did a modified the Hoschkerz (sp) route: Mash in at 142, decoct and add back for 159, decoct again for mash out. I missed my 159 rest when I added back in, added some water to get there, and probably didn’t hit the mash out temp either. The result was a magnificent BoPils.
In the end, it was fun to try. But I think you can achieve much of it in other, less time consuming ways. That’s not to say I might not do it again when I forget that long brew day or others that followed with just doing the mash out like you did.
For the original poster - tell us how that beer turned out when it is done. You might be surprised at how it is. Let us know. If it is good you do not suck at decoctions.
Given the limitations of my system (namely, not having a direct-fired mash tun), I have started only doing decoctions to hit mashout temps. If there are additional starches released during the mashout decoction, they haven’t been a problem in my beers. My beers clear very quickly without finings.