I’m brewing a BoPils today for which I’ll do a Hochhurz decoction mash (Beta @ 145, Alpha @ 158). I did a lot of searching on the web last night for thoughts on decoction and I’ve noticed that there seems to be a lot of variation between how long brewers recommend boiling the decoction. I’ve seen a general range of 15 - 45 minutes. And I’ve read that one should aim for the low end of the range for lighter beers (e.g., helles); the high end should be used for darker beers (e.g., dunkel). But then I came across some posts on another homebrew forum where a brewer that I know to be fairly well-versed in decoction indicated that you basically won’t get any flavor benefit from doing a decoction unless you boil it for at least 45 minutes.
For all of you brewers out there who do decoction mashes, how long do you boil the decoctions. Is it style/color dependent? Do you do a one-size-fits-all boil time? Should I be boiling my thick decoctions longer/shorter than my thin decoctions?
It takes me about 8-10 minutes to get a decoction up to a boil. That’s all I do, then I add it back. But then I’m only expecting a decoction to raise the temperature of the mash.
I just mashed in at my beta rest temp. I think I’m going to do a 15 minute boil for the first decoction and a 30 minute boil for the second one. For something like a dunkel, I might do 30 minutes for the first boil and 45 for the second.
In the experiment I did, a single decoction with a 30 min. boil was found to make no significant difference in beer flavor. Given that, I’d recommend a longer boil and/or multiple decoctions.
I get better efficiency with decoction, plus it seems to result in more body. After bringing the first decoction through an alpha rest and then to boil, I don’t think you need to cook it that long to get your results.
I ended up boiling the first decoction for 20 minutes and the second for 30 minutes. Hit all my numbers so far (knock on wood). I’m currently about halfway through a 90 minute boil.
I’ll be brewing a dunkel in a few weeks. Thinking I’ll boil the first decoction for 20 minutes again, but I’ll boil the second one for 40 minutes. I just brewed this dunkel a few weeks ago with a single infusion mash. I’ll be doing some side by side tastings when the double decocted one is ready.
I made a very nice Vienna lager with a triple decoction where the boils were only 10 minutes each. It scored upper 30s and a 2nd place ribbon in a BJCP competition. 10 minutes was plenty to get the job done, and it only added like 30-45 minutes to the brew day (this was a 3-gallon batch, mind you), which was totally doable. I’m not the type who enjoys brewing for 6+ hours – no thanks. Git 'er done.
I think that this question, this discussion, presupposes that decoctions deliver a flavor impact. I think that while there is a large impact as a result of decoction mashing the portion of that impact that relates directly to flavor is small.
When I do decoction mashes the beers they produce, to me, taste the same as stepped mash beers where I hit the same steps. I do think there is an impact of decoction. I like Eric Warner’s reasoning in German Wheat Beer:
[quote]A single or double decoction mash is used when brewing a Weissbier wort for three main reasons. First, it supplies the yeast with an adequate amount of amino acids. Second, it breaks down the higher-molecular-weight proteins […] Third, […] it reduces chill haze in the final product.
[/quote]
That’s it, those are the only reasons mentioned. I would add two reasons - 1. Further breakdown of starches than with a traditional mash, ensuring full and complete conversion and, potentially, a higher extract yield and 2. The residual body benefits of a stepped mash procedure (really dry and yet really malty).
I actually heard Charlie Bamforth of the brewing with beersmith podcast say (paraphrasing) that the only reasons large breweries step-mash is to improve runoff and on a homebrew scale it makes no difference. Of course, he then went on to say that he has never homebrewed and tries to avoid drinking homebrew, so what does he know about it?
You’re right, I am assuming that. And I admit that I haven’t done enough comparisons between step-mashing w/decoction and straight step mashing to validate my assumption.
Going forward, I think I will try varying my thick decoction boil times (between 20-40 minutes, depending on the style), which, for me, is the decoction step between the beta and alpha rests. My second decoction – the thin one – will only be heated to boiling and will then be added back to hit a mashout temp of 165-167.
What I’d like to see (what everyone wants) is a definitive experiment. I’m talking controlled, double-blind, triangle-tested, standard-deviation-recorded, ACTUAL experiment. An experiment upon which one, at a homebrew level, could draw a definitive conclusion. My constant rant about homebrewing is that so called experiments don’t stand up to scrutiny (i.e. I brewed two beers and one tasted better - really?). Let’s go after this like we’d go after FDA approval – where’s Mashweasel? Who knows how to structure and experiment? Who knows statistics? I know that my data points are insufficient. I’ll help in any way I can if someone can tell me how to factor out randomness and bias. Let’s actually produce something.
thcip, it’s already been done. Denny will tell us where to find the results of his blind triangle test that proved no discernible benefit of decoction versus infusion.
That being said… I’m still not convinced any way or the other that there’s not a taste difference, as my triple decocted beer was the finest lager I ever made compared to using regular infusions. I’ve made some good lagers, but never THAT good as when it was decocted. Was it a fluke? I don’t know. I was actually running an experiment with two brews back to back with the one triple decocted and the other single infusion, but alas… the single infusion beer got contaminated for whatever reason and had to be dumped. So I’ll need to run the experiment again one of these days. So many experiments I need to run, so little time…
If I accept that step mashing makes a difference for my German lagers, I’m not really concerned with whether infusion step mashing or hitting my steps with a decoction makes a difference. On my system, I’ve found decoction mashing to be the most efficient way to hit my step temps. If it adds a flavor component, that’s great. If not, no big deal. So while an extensive and properly conducted experiment might yield an interesting data point, it probably wouldn’t change my current practices much, if at all. If such an experiment conclusively determined that decoction does not contribute to a beer’s flavor, the only thing I might do differently is to apply a standard, shorter decoction boil time across the board. But I wouldn’t likely stop doing decoctions altogether.
