View Full Version : Decoction: any actual benefit?

12-17-2003, 10:15 AM
I usually read the "Brewers Wanted" section here, just in the off chance that a job will come along that is too good to pass up, and one recent posting for a brewpub near me specified that they use "decoction method".

Now, I know what decoction is, and that it was originally developed by German brewers to maximize extract to get around a tax on raw materials. My question is, without any strong financial reason to keep your grain bill down, are there any other reasons to prefer decoction over infusion?

I'd note that, while I'm personally more of an English ale kind of brewer, I've brewed German-style lagers without any problems (fit flavor profiles, tasted good!). I haven't done a decoction, and obviously my comfort level with infusion is high. Based on descriptions of decoction, it seems like a lot of work for unclear benefit...

Please, set me straight!

Cheers, Tim

Chip Tate
12-17-2003, 01:20 PM
Michael Lewis at UC Davis would agree with you, from what I understand. He argues that while decoction can affect wort profiles and taste, these differences can also be affected by using different malt profiles or mash temperature regimines.

I'm on the fence myself. I've done a lot of decoction and I do see some differences in the beer some of the time--particularly where foam is concerned. When I do full decoction regimes with malt bills that contain some light caramel, munich, vienna, etc. The foam seems to be rockier and leave little floating islands of protein in the beer even once the head falls while drinking.

On the other hand, maybe I notice a difference because I want to see one. After such a LONG brew day, I NEED to see one to justify all the extra work.

Best I can tell, the pendulum of consensus seems to be swinging toward the infusion being just as good as decoction side. But I think there are still some big Euro brewers that could save a lot of money in energy costs by doing infusion instead of decoction and have not switched--so they must think there's a difference.

I'd also be really interested to hear what those with experiences with both methods have to say.


12-19-2003, 09:36 AM
Yeah, I figured that the technique itself would produce certain flavor characteristics, but it seemed to me they could be reproduced via recipe/mash temp adjustments in an infusion mash.

And I'm all about being lazy!

Hopefully, someone else who's done decoction will chime in.

Cheers, Tim

12-19-2003, 10:40 AM
Many years back, A VP for a large US malt producer told me that decotion and step mashing was the product of history and homebrewing myths. In the past, european malt was undermodified and thus required the additional steps. US malt houses, and more and more european malt houses produce fully modified malt that does not require the additional steps. Unless you are importing undermodified malt, you are probably wasting your time. In fact, I know of one brewer who uses an extremely short mash time, (he's in, he's vourlaufing, he's out) and produces great beers.

dick murton
12-22-2003, 05:26 AM
I could have sworn I had posted a comment to this already. Unfortunately it is a little longer than space will permit, so please see the attached file for my two penny worth.


12-22-2003, 06:35 AM
Dick- I don't see an attached file. If your message was too long for one post, feel free to split it into two parts and post them sequentially. I'm looking forward to reading it!

Cheers, Tim

dick murton
12-22-2003, 08:04 AM
Part 1
Don’t forget that the reason decoction mashing took off was because temperature control was not particularly good, thermometers being non existant or very expensive. With standard isothermal mashing, the brewer allowed a puddle of hot water in the mash tun to cool down so he could just see his reflection, this giving roughly the right overall mash temperature for the enzymes to work – which was great for darker beers. The desire to produce pale beers meant that malting processes had to be altered, and the beer produced was not perhaps as good as with more highly modified, higher coloured malts. Presumably by trial and error, someone worked out that taking fixed proportions of a cool mash out, boiling it and adding back resulted in suitable temperatures for different enzymes to work OK, and by repeating the partial boil procedure, allowed reasonably efficient production of pale coloured beers.
As for as modern production methods – I have used or worked at breweries using rising temperature infusion mashes (using mash mixers), or single fixed mash temperature only (in mash tuns), producing ales and lagers alike, using pale malts quite happily in all of them. Modern malting allows production of well converted, pale malts that can cope with simple rising temperature infusion mashing or single temperature mashing, producing pale beers. If they need to be really pale like certain American lagers for instance then it may be necessary to use, say maize, rice or sugar syrups to dilute the colour.
Where whole grain is added as adjunct, the starch needs to be gelatinised to allow the malt enzymes access to it, and this is traditionally carried out by boiling. However as these can be obtained pregelatinised, there is no need to boil them up separately and they can be added directly to the mash vessel, normally at mashing in. The lack of boiling also means that extraction of the anthocyanogens in the malt husk is reduced, i.e. less potential haze forming material, and thus reduced post fermentation treatment – cold storage times, silica gels, PVPP etc may be possible.
In other words, I for one, also see very little justification for the end product quality requiring use of traditional decoction mashing. If you want to do purely for marketing reasons, fair enough, but there is extra cost arising from the additional plant, cleaning and time required. One key point is to ensure the mash is stirred and mixed thoroughly, and heated rapidly without burning onto the heating surfaces of the vessel.

dick murton
12-22-2003, 08:07 AM
It appears I don't need a part 2. Last time I tried something this long, it was bounced back.

Hope you have all been busy brewing for Xmas & the New Year. Have a good'n


jason webb
12-22-2003, 01:57 PM
I was the head brewer at Saxer brewing co. for six years. We had a nice range of balvarian stly lagers where we used this method. Portland Brewing co bought our brewey in 2000. If you tasted saxers decoction mash beers and compared them to pbc you would know the differance!!!!! I know you get a unique flavor from decocotion mashing. 100 c transfered to 52 c gives you 72 c.
anyway good luck.


12-23-2003, 08:28 PM
Hey J.W.,

While I'll agree with Jason that decoction brewing may produce sublte taste differences I think it is highly unfair to compare a brand that has been acquired and then brewed at another location. (I worked for Saxer too!!) There are just too many variables like malt supplies, equipment, staff, and different brewhouse characteristics when comparing a lager that was once brewed decoction style and later brewed step infusion. If there is indeed a taste difference(?), I think the malt bill could be adjusted to compensate for flavor differences. Generallly speaking my brewing education has been strongly influenced by the schools and testing programs of the U.K. Generally all the brewing theory from this region of the world (U.S. included) suggests that with high quality, highly modified malts decoction is somewhat unneccasary, therefore I agree with Dick and his post. Ultimately ii will just end up costing more $$ to make beer and possibly shut the doors for a struggling brewery. While it might be great to "tout" your beer as being brewed by laborious Bavarian standards will it really result in selling your product. I doubt it? I remember three decoction brews taking close to 18 hours to produce, can you say cha..ching. The majority of customers simply want clean, consistent, refreshing beer. Hopefully this task will net the brewery some positive cash flow in the process.

12-23-2003, 09:36 PM
Thanks for your imput! Lots of good information here.

Cheers, Tim