History of decoction mashing is... ...wrong?

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Crucial-BBQ

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The history and reasons behind decoction mashing according to many brewers seems to follow that the technique was developed for reasons of under-modified malts and/or lack of thermometers. Through my own research the former seems to hold some truth, with a few caveats mind you, yet the latter seems totally false.

Because of the amount of information collected, I will present my findings here in "bulleted format" for easier reading.

Part 1; under modified malts.

-European malts contain less protein than do North American malts. Sticking with only the U.S., it goes, from highest protein content to least: U.S. 6-row --> U.S. 2-row --> Continental 2-Row.

-Continental (European) 6-row is higher in enzymatic power yet malts with higher protein content have been viewed as "garbage" in Bohemia since at least the 1700s. As an aside, English brewers were to the first to describe American hops as "catty" as early as the early 1800s with references of cattiness to both the piney aroma of American hops and/or to the "blackcurrant" of Cluster hops.

-The barley favored by Bohemian brewers had barley corns with "fine husks". It is most likely that these malts were under modified because well or full modification resulted in brittle corns that turned to dust when milled.

-According to Briess, Rarh, Weyermann, and a few others the end result of the malting process--the modification--has remained relatively the same for hundreds of years. So, the under-modification of Bohemian malts was done on purpose based on advanced malting experience and know-how; not out of stupidity or inferior product/process.

Part 2; the decoction process.

-Decoction is the process of extracting "what is desired" from plants and herbs and as a technique has been around for thousands of years. It was how ointments, tinctures, and other medicines were made as well as how teas and if I remember correctly even coffee were originally once brewed. So, German brewers surely knew of the process and its potential to get "more beer" from the mash.

However:

A. The three earliest references to the more popular German beers I have found so far include a top fermented wheat beer, a bottom fermented wheat beer, and something that was the precursor to what later became Pilsner/Helles/Dortmunder and so on.

I have read through History of German brewing as written by Germans and found that the conclusion of decoction mashing was the result of trial and error. My guess, based on my research, is that decoctions may have originated through the higher usages of unmalted wheat, rye, oat, and so on.

B. I have yet to find one research paper or reference that gives a date of the first decoction mash let alone a ball-park century. The history of decoction mashing seems to be more round-about than historically factual.

B1. Germany is cited as the first Country to do decoctions yet Pilsner Urquell is the first brew/brewery to utilize decoctions. Pilsner Urquell did not come onto the scene until, what, the 1840s?

B2. Sometime in the mid-to-late 1700s mashing techniques went from single step to triple step in Bohemia but it is unclear if this were a direct-fire step mash or decoction. Which came first?

B3. Thermometers were invented in the 1500s, then finally standardized in the 1700s. They were also used in the early roots of what was to become Pilsner Urquell beginning something in the mid-1700s.

C. Pretty much every German/Bohemian brewery and technique that we now refer to as traditional were established in the 1800s; at a time when brewing, let alone agricultural science and science in general, were fairly well understood. Everything prior to the 1800s is simply "old" but not necessarily "traditional".

So, the thermometer reason goes out the window. Also, without thermometers how would a German brewer know how much to decoct, let alone how much decoction to add back, if the goal was to reach the next step temp if the concept of "measured temperature" was purely science fiction at the time? Impossible, right. If they were doing it without thermometers they were simply going of prior knowledge of "hey, if we pull this amount of decoction well get this result. This goes back to trial and error; it was not to reach a specific rest temp.

-There is evidence that English brewers at one point in time were doing multi-step mashes prior to the Industrial Revolution as evidenced by the "Second revolution of English brewery design" that were built specifically for single infusion mashes. The English were also the first to specifically modify barley corn for single infusion (that is, full modification). The merits of step mashing and the various rests have been known about for a very long time, yet, the English never did decoction mashes.

Part 3; cultural and economic influences.

Germany was probably the first country to seriously mass-produce beer for public consumer consumption, yet England was the first to dominate global export of beer. Germans had developed a preference for darker Munich type of beers and other German styles may have been influenced by English porters and ales as early as the mid-1700s, yet, most favored--in particular Bohemian beer drinkers--the bottom fermented beers and beers produced with less protein-rich malts (cloudier).

Also, as beer production increased, demand for a more "clean" product, and costs began to rise it is also possible that decoctions were favored because they tend to help produce a more clear product, and, with the breakdown of cell walls "releasing" more starch, the ability to get more beer from less grain, and, as a technique to help create beers influenced by U.K. brewers.

This was largely posted for fun, as I am a nerd for this kind of stuff, and of course my research has been limited by time and lack of access (some of those antique brewing books are expensive and I don't have journal subscriptions to any brewing journal). My point main points were to dispel the myths of "lack of thermometer" and under-modified malts.

Also, the phrase "today's well-modified malts" and/or "today's malts" goes back in brewing literature to the 1940s as I have found so far and Briess contends that the malting process has not changed in over 100 years despite the advent of newer technology. European malts have more recently been engineered to produce more protein, but this was likely more from pressure of newer breweries who do not have the space, or money, to spend on decoction mashes. Yet, many brewers of yore who once championed triple and double decoctions are now still doing altered double or single decoctions. Sam Adams and Bud, here in the U.S., still employ single decoctions although in the case of A.B. that may just be a separate cereal mash.

Pilsener Urquell is still doing the triple decoction, yet, I found some evidence that suggests they did not even begin doing the triple decoction, or any decoction in general, until the early 1900s.

What do ya'll think?
 
AB does ramped infusions, not decoction.

Some interesting stuff there.

So, the thermometer reason goes out the window. Also, without thermometers how would a German brewer know how much to decoct, let alone how much decoction to add back, if the goal was to reach the next step temp if the concept of "measured temperature" was purely science fiction at the time? Impossible, right. If they were doing it without thermometers they were simply going of prior knowledge of "hey, if we pull this amount of decoction well get this result. This goes back to trial and error; it was not to reach a specific rest temp.

I would think it certainly was to reach a specific temperature. Perhaps they didn't know what that temperature was but they did know that if they followed a specific procedure of adding heat that the beer would turn out how it was supposed to. From tanning to dyeing to preserving by salt or smoke there are many pre-modern methodologies that were discovered and refined over time by trial and error and/or a series of happy accidents. I would not be surprised if many brewing techniques developed the same way.
 
Here are my two thoughts:

1) I doubt that thermometers were widely used until Fahrenheit and Celsius standardized scales. Up to that point, most thermometers were unique and many were open and subjected to atmospheric pressure changes. Which means the 1720s - 1750s for general usage.

2) I think the undermodified malt theory has a lot of merit. If you think about a decoction mash, it's basically a series of cereal mashes. You dough in roughly at the gelatinization temp for barley (140F). If it's a wheat beer, it's 136F and that just also happens to be close to the protein rest range.

Then you pull a portion off and do a cereal mash (boil for 30 minutes) and add it back to the main mash. Then you pull off another decoction and do another cereal mash, etc, etc.

You only need to do cereal mashes when you have under or unmodified malts.
 
As someone who uses a cooler mashtun, I find that decoction is really the best way to do a german style step mash with my equipment. I've wondered if that might have influenced the Germans. You have a larger vessel for the mash with no heating capabilities, and a smaller vessel with direct fire to heat the initial water and the decoctions. In your research did you find equipment limitations to be an influence in the use of decoctions for step mash?
 
Think you can mock up the original with a bit more citations and/or references?

Good piece of work.

Check out New Brewing Lager Beer - Gregory J. Noonan ISBN-13 978-0-937381-82-3
 
This is something that has bugged me most of my life. Not this exactly, but the general idea that "We" the current people of this earth are the only ones capable of figuring anything out and yet at the same time we give credit to some of the most significant discoveries in science to people that lived centuries ago.
ex. experts can't figure out how they built the pyramids.
so what. obviously they did and the people that designed them way back then were probably more intelligent then the experts that can't figure it out today.
Just because we have more knowledge available today doesn't mean that everyone is more intelligent. Engineers with no letters behind their names built structures all over the world that have stood for centuries and yet there are plenty of people with doctorates today that couldn't build an arbor that would stand one season.
Successful growers and brewers back then are probable just like today. Intelligent or lucky. The idea that "trial and error" is an inferior process to scientific knowledge is really laughable and I believe that a lot of what happens today is still really trial and error using the excuse of science and knowledge.
I read everything I could when I got into brewing and I still tried and 'errored'
 
I think they could tell a lot about whether the mash was around the right ballpark by looking at it rather than using a thermometer. Surely it's less accurate, but if you do it day in day out you can tell a lot from the smell, vapours, look of the mash. I'm quite sure I read a written description of what mashes look like in a Georgian / Victorian British brewery somewhere. They adopted thermometers fast, though.

Btw, weren't Scottish breweries the first ones to extensively use single infusion? Most breweries south of the border used multiple mashes till the mid 1800s.
 
So, the thermometer reason goes out the window. Also, without thermometers how would a German brewer know how much to decoct, let alone how much decoction to add back, if the goal was to reach the next step temp if the concept of "measured temperature" was purely science fiction at the time? Impossible, right. If they were doing it without thermometers they were simply going of prior knowledge of "hey, if we pull this amount of decoction well get this result. This goes back to trial and error; it was not to reach a specific rest temp.

But it would be to reach a specific rest temperature; even if they didn't know exactly (in numerical terms) the that temperature was. For any particular brewery the boiling point of water would remain constant. Likewise, the thermal mass of water and grain also remains constant. So while they didn't know the exact temps they were hitting, and had come across those procedures through trial-and-error, heating a consistent portion of the mash to boiling (i.e. a consistent temperature) and reintroducing it to the main mash would consistently raise the temperature the same amount. Physics isn't arbitrary, even if the person using it doesn't understand the physics.

And I snipped the section on the malt quality bit, but I'd be cautious about using modern malt modification information a a proxy for patterns of historical malt modification levels. Malting has undergone a revolution since the early 1900's; a poorly modified malt today is better modified than the best modified malts of the 1800's (never mind the 1700's or earlier). It took the mechanization of the malting process and the development of industrial heating and ventilation before the nicely modified malts of today were anything more than a maltsters wet dream.

Bryan
 
....loads of really interesting stuff, seemingly with a lot of time and effort gone into the research....

Wow. Really interesting stuff there. Thanks

Would you consider submitting this to the Technical Articles and Write-ups Forum. The editors could clean it up (if needed) and @Austin could publish this on the front page of HBT.

What do you think?

+1
 
Would you consider submitting this to the Technical Articles and Write-ups Forum. The editors could clean it up (if needed) and @Austin could publish this on the front page of HBT.

What do you think?
Yes, definitely.

AB does ramped infusions, not decoction.

Some interesting stuff there.



I would think it certainly was to reach a specific temperature. Perhaps they didn't know what that temperature was but they did know that if they followed a specific procedure of adding heat that the beer would turn out how it was supposed to. From tanning to dyeing to preserving by salt or smoke there are many pre-modern methodologies that were discovered and refined over time by trial and error and/or a series of happy accidents. I would not be surprised if many brewing techniques developed the same way.
My understanding is that AB performs a cereal mash, which is a pseudo decoction, which when combined with the main mash raises the temp. So yes, an infusion ramp mash.

My issue is that when we think about past techniques we tend to do so with bias formed by current knowledge. Simply put, we can't speak of things in terms of temperature if even just by correlation. They surely did have some forms of measurement; my guess by measurements in volume (pulled volume of decoction) and time (boil decoction for X amount of time).

Decoctions predate "modern" brewing by a long shot (by modern I mean when brewers moved away from loaves of bread onto mashing the grain itself), and even distillation has been around for a really, really, long time. Realistically, the idea of decocting the mash would have already been known to brewers whether there was a need for it or not.

Malting processes may be the same as 100s of years ago, but is the barley?
Yes, the barely has changed. I am not sure about in other countries but here in the U.S. the #1 use for barely is animal feed. Then of course, brewing. In order to maintain the competitiveness of barely against other grains is to continuously push for the creation of a better and better product.

Malting grain is simply controlled germination. Nothing specialized about it; you could easily do it at home. The earliest known malthouses are some 5K years old. And to this day there are now artesian maltster who insist on malting the old fashioned, labor intensive, way. If they can do this, malt grains in the most basic, pure, manner and still result in well-modified malts then that is evidence that it is not the technique in question.
 
Malting grain is simply controlled germination. Nothing specialized about it; you could easily do it at home. The earliest known malthouses are some 5K years old. And to this day there are now artesian maltster who insist on malting the old fashioned, labor intensive, way. If they can do this, malt grains in the most basic, pure, manner and still result in well-modified malts then that is evidence that it is not the technique in question.
This is, to be blunt, completely and utterly wrong. The history of malting is well known, well researched, and extensively written about. That malting methods have changed drastically over the past few centuries, with concordant improvements in malt quality, is an established fact. Those 'artisan' malsters you refer to use floor malting; a method established only in the mid-1800's, and most roast their malts using kilns developed post-1950's (hence 'artisan' in quotes).

The European malt houses used when decoction appears to have been invented used cistern malting - deep tanks were filled with grain and water and left to soak for 1 to 2 days. The grain was then moved into piles; if the grain got too hot the piles would be spread out, if it got too cold the grain would be re-piled and covered in straw. 9-15 days later germination would be complete, and the malt would be dried in wood-fired kilns. These malts had ~50% less diastic power, ~30% less fermentable yield and were much less friable than modern malts. They also would have a modest smoked flavour/aroma (from the use of wood-fired kilns) and would often have notable lactic character due to the growth of lactobacillus - this was such a problem that in many places laws were passed to block malting in the summer months. This process slowly evolved into floor malting (circa 1750's), although this method didn't become what we would recognize as floor malting until the early 1800's.

Malt houses more than ~1100 years old are not known - malt kilns go back to ~4000BCE, but the oldest known malt houses date to ~900CE. Prior to that, most malting in Europe/Middle east was done in peoples homes by a method called pot-malting; malt was soaked in small quantities and left in clay pots to sprout. Go back far enough (e.g. ancient Egypt) and you'll find malt being made by soaking sacks of grain in water troughs or clay pots. In mesopotemia, apparently unmalted grain was baked into bread, and the bread itself malted.

Even in the modern era (post-1800's), malting has advanced a lot. The late 1800's and early 1900's saw the development of compartment malting, which featured forced-ventilation and agitation machines. Most modern malting facilities use a similar system, but include into that temperature control, dried air, etc. We know, quite well, that changes in barley breeds had little to do with the improvements in malt quality over the same period of time.

Along the way malt quality has changed drastically. Archaeologists have reconstructed many of these methods to see how well they work, and amateurs like myself have (on occasion) tried them ourselves. Even with out modern knowledge, most home malsters would be hard-pressed to produce fully-modified malt.

There are lots of good books on this topic (many with DIY sections). Some freely available ones (check gutenburg.org and archive.org) include 'Malt and malting, an historical, scientific, and practical treatise' by Henry Stopes, and 'A theoretical and practical treatise on malting and brewing' by George Adolphus Wigney. If you're willing to shell out some $$$ for books, 'A History of Beer and Brewing' by Ian Spencer Hornsey is excellent and 'Malt: A Practical Guide from Field to Brewhouse' by John Mallett has a good historical section.

Bryan
 
My understanding is that AB performs a cereal mash, which is a pseudo decoction, which when combined with the main mash raises the temp. So yes, an infusion ramp mash.

Well, a cereal mash and a decoction mash aren't the same thing. Yes they do a cereal mash to cook and hydrate the raw rice. IIRC the cereal mash is added to the main mash providing a main mash starting temp in the low-mid 120sF. The main mash is then slowly and continuously raised in temperature (the ramped infusion) to the main rest stage. After that a very long sparge by homebrew standards sucks every last sugar molecule out of the grains.
 
@Bryan,

The process of malting is simply coaxing the kernel into germination via water followed by a cool drying process; the point where starches are converted to sugars in preparation for sprouting. After this, the grain is then heated to produce the desired characteristics. Yes, the process has changed but that does not change the fact that at its core it has remained the same. I mean take gardening for example. You want to plant tomato and have a good amount of resources at your disposal: seasonal planting guides, fertilizers, gardening tools, a hose, and so on. You get nice, big, tomatoes that win you a ribbon at the county fair. That still does not change the fact that at the end of the day, to grow a tomato plant, only requires you to scatter some seeds and apply some water.

I am not arguing that the process has not changed nor has not changed for the better. I am saying that if you broke the process down into its most basic functional sections it is rather simple.

I beg to differ on the dates of the oldest known malthouse, but will have to check my source for clarification.

I appreciate your response and that link looks like a good read (which I will get to later). I will also check into those dot orgs.

And I'm always looking for new books to add to my collection :mug:

Well, a cereal mash and a decoction mash aren't the same thing. Yes they do a cereal mash to cook and hydrate the raw rice. IIRC the cereal mash is added to the main mash providing a main mash starting temp in the low-mid 120sF. The main mash is then slowly and continuously raised in temperature (the ramped infusion) to the main rest stage. After that a very long sparge by homebrew standards sucks every last sugar molecule out of the grains.
A cereal mash begins in a separate kettle along with a small portion of base malt. It is raised to a sacch rest temp, held there for 30 minutes or so, and then ramped to boiling. If doing grits, as I did just two days ago for a cream ale, the boil is for between 45 - 60 minutes until, as in my case, the grits gelatinize.

So no, technically they are not the same thing since the cereal mash is not pulled from the main mash. Like a decoction pull (which I am also a fan of), the cereal mash is ramped to a rest temp, held, and then ramped again to boiling.
 
I still think decoction adds/does nothing to the beer. Pilsner Urquell might get more of its malt flavor because they boil for like 3 hours, not decoct. That's my theory anyway. Having done decoctions over the past few years, I've never thought, "Oh this is maltier because I decocted this beer. There's just something there that decoction added..."
So I guess with that, the reasons for decoction throughout history doesn't matter much. The undermodified malt theory is a pretty good theory. It boosts extraction. That's good! I've heard a lot that many German breweries don't even decoction anymore, but do step mashes.

Having said all that, I still do them now and then, just for kicks.
 
I still think decoction adds/does nothing to the beer. Pilsner Urquell might get more of its malt flavor because they boil for like 3 hours, not decoct. That's my theory anyway. Having done decoctions over the past few years, I've never thought, "Oh this is maltier because I decocted this beer. There's just something there that decoction added..."
So I guess with that, the reasons for decoction throughout history doesn't matter much. The undermodified malt theory is a pretty good theory. It boosts extraction. That's good! I've heard a lot that many German breweries don't even decoction anymore, but do step mashes.

Having said all that, I still do them now and then, just for kicks.

I've often wondered about the longer wort boil of Pilsner Urquell giving it that extra something. The decoction even adds more boil time so one of these days I'm going to try a long 3+ hour boil time with 100% Pils malt and see what happens.
 
Would you consider submitting this to the Technical Articles and Write-ups Forum. The editors could clean it up (if needed) and @Austin could publish this on the front page of HBT.

What do you think?

As a few people have said, that's a great idea. I understand getting the time and resources can be tricky, but I think this would be a fantastic article if you could cite the sources you used.
 
I'm just curious...how would you go about malting a loaf of bread??

If you google for 'bappir' you'll find the recipe & all the details. Long story short, after cooking the bread was soaked for several days in water along with dates. The residual enzymes in the bread (plus, likely enzymes from the wild bugs from the dates) break down the starches which are then fermented.

Bryan
 
If you google for 'bappir' you'll find the recipe & all the details. Long story short, after cooking the bread was soaked for several days in water along with dates. The residual enzymes in the bread (plus, likely enzymes from the wild bugs from the dates) break down the starches which are then fermented.

Bryan

Breaking down starches=/=malting.
 
I've often wondered about the longer wort boil of Pilsner Urquell giving it that extra something. The decoction even adds more boil time so one of these days I'm going to try a long 3+ hour boil time with 100% Pils malt and see what happens.

This would be great for a brulosophy blog. Do a single infusion (90 vs 180 min boil) vs decoction (90 vs 180 min boil). But that would be a ridiculous brew day and yield a sh!tton of beer. Would make for a good club experiment I suppose. Do post if you ever do such a thing.
 
Breaking down starches=/=malting.
In this context, the processes may be parallel; one thing not clear from history is whether the grain was partially malted in advance. Some reconstructionists claim to get conversion with flour from unmalted grain (I did not achieve this with my attempt, and had to add base malt to complete conversion), which would mean that amylase development/release (i.e. one of the biochemical processes which occur during malting) would occur in the bread. Much of the other modifications that occur during malting (e.g. freeing starch from its matrix) is achieved by grinding grain to flour.

B
 
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