Adjuncts, starches, and sour beer.

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metic

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Dave Marliave was on the Sunday Session recently talking about adjuncts in sour beer. One interesting thing he mentioned was the ways in which they try to get starch into their wort. A traditional turbid mash will do this, but he also mentioned getting starches by adding adjuncts, in particular by steeping flaked oats after the mash so that their starches do not convert.

I was rereading Wild Brews recently, and I noticed that Jeff Sparrow mentions something along the same lines with respect to the use of corn in Flanders Reds and Browns. This is from pp.122-3 (my bold):

Maize (a.k.a. corn) can comfortably make up around 10% of the grist of a wild beer and can go as high as 20%, although that amount can cause the lauter to seize up. Generally used for both economical and flavour considerations, maize will add starch, considered beneficial to lactic acid bacteria over the course of fermentation. According to Peter Bouckaert, beer brewed with a starch adjunct such as corn is lighter and more digestible.

Two types of maize exist: corn grits and refined corn grits. The former is cheaper, dry milled, and requires cooking times of up to forthy-five minutes, while the latter is wet milled, nearly pure starch (very desirable to bacteria), and requires only about fifteen minutes. As a substitute, flaked maize comes already gelatinized and can be ordered from your brewing supplier, although it will not add as much starch as raw grain with an adjunct mash.

The idea behind all of this is that the starches take a long time to break down, which gives the souring bacteria more food over the course of the fermentation. Dave Marliave also mentioned that, since these starches will initially breakdown into sugars, and this itself might take a long time, the overall effect can be one of slight sweetness and body in a beer that is already a year or more old---a flavour profile he seemed to like. (This seems to go a little against what Peter Bouckaert says int he quote from Wild Brews.)

Presumably these sugars will eventually be fermented as well, and you'd have to keep that in mind if you were bottling a year old beer. But the overall effect seems to be a more complex and developing flavour profile over the course of the beer's lifetime. Dave Marliave says that this is something you won't get from maltodextrin (or, I presume, from mashing high) because even though the saccharomyces won't be able to break down these sugars they will be broken down and fermented over the course of a year by the brett and bacteria, long before you would think about bottling. (You would still get added sourness though).

Anyway I'm curious if anyone has tried anything along these lines, beyond a typical turbid mash, and what effect its had. I'm brewing a beer this evening, to be fermented with what's left of a vial of bug county, and I think I'll steep some flaked oats in the wort just after mash out to see how it effects the final product.
 
Subscribed. Eager to read about the results.

I wonder if adding wheat starch to a basic mash would have a similar effect?
 
On my last sour brew I scooped out 1 gallon with grains from the mashtun 5 minutes after mashing in and brought it to a boil. I kept this separate till it was time to mash out. I added the 1 gallon back to the mashtun and drained it before batch sparging. It's not a true turbid mash but it should supply some unconverted starches. I also added maltodextrin in the boil. I don't know what the results will be like but it seems like a good idea in theory.
 
That is a very good idea indeed.
Think I may use this on my next sour brew.
 
On my last sour brew I scooped out 1 gallon with grains from the mashtun 5 minutes after mashing in and brought it to a boil. I kept this separate till it was time to mash out. I added the 1 gallon back to the mashtun and drained it before batch sparging. It's not a true turbid mash but it should supply some unconverted starches. I also added maltodextrin in the boil. I don't know what the results will be like but it seems like a good idea in theory.


I did something like this when I brewed a lambic-style wort a month ago. I couldn't do a proper turbid mash, so I took a couple of litres of milky liquid from the mash at the start, and boiled it along with a small adjunct mash of unmalted wheat, then added it back to the main wort at mashout.

Also, few months ago before I read any of this stuff about adjuncts, I was thinking about turbid mashes etc. and decided to try something with a pale sour I was brewing. I usually do 3 gallon BIAB batches, crushed with a corona mill, and that leaves me with a fairly cloudy wort. Whirlfloc usually takes care of that, but I decided to leave it out to see if this changed the fermentation at all. This is different from the process I used to day, because I was not adding any starches after the mash. It's only a few months old at this point, so it's hard to tell if this is making any difference.

Today I steeped about 200g of flaked oats after mash-out---so at about 180-190F---while the wort was on it's way to boiling. I also skipped the whirlfloc again. The result, as expected, was a very cloudy wort.
 
I've also heard on one of the radio shows that wheat flour can be used in place of adjucts to the tune of about a tablespoon in 5 gallons added directly to the boil. This would give the starches that brett and bacteria can feed on to assist in the souring process.
 
They were referring to beers like pseudolambics and saisons that don't get flaked wheat in the mash. Their yeasts don't flocc out and the bacteria chew those starches.
 
I'm brewing 10 Gal of a blonde sour tomorrow. Any idea on what percent maize and/or steeping oats might be beneficial? I'll be fermenting with ECY20 and bottle dregs...
 
I'm brewing 10 Gal of a blonde sour tomorrow. Any idea on what percent maize and/or steeping oats might be beneficial? I'll be fermenting with ECY20 and bottle dregs...

The recipes in Wild Brews have about 10% maize. That is included in a cereal mash though. I can't remember if Dave Marliave gave figures in the Session podcast, but I tried around 4% flaked oats, and ended up with a very cloudy wort.

If one were to steep the oats separately, at what temperature would be a good temp? Perhaps 168F for 20 minutes or so?

I think that would be fine. I steeped them in my wort after the temperature was high enough to denature any enzymes from the mash, so at around 190. Dave Marliave said they put them in the grant between the mash tun and the kettle. Here's a link to the original show if anyone is interested:

http://thebrewingnetwork.com/shows/1027
 
I've actually followed Dave's process twice so far and have documented it -

http://onlinebeerscores.com/blog/sour-belgian-brown-ale-write-flat-tail-process-take-ii/
http://onlinebeerscores.com/blog/belgian-sour-stout-brew-day-write-up/

The first link is about as close to their process as I was able to get.

I've been thinking about this for a while after making a fairly sour Berliner Weisse (https://www.youtube.com/watch?v=_hClp9huB1M). I couldn't ever think of a reason not to let the Lacto sit for a few days before pitching yeast in any other sour beer style. I recently pitched the Wyeast Lacto at the same time as the yeast and didn't get nearly the sour level that I've been able to get from cultured commercial bacteria/yeast.

I don't have much space to store things, so my sour brewing is slow, but the next time I have a chance to brew a sour from a pure Lacto culture, I am definitely using this method. Good to know I am not the only one thinking on these same lines.
 
Could you suspend the oats in a large hop bag in your kettle?. Then after sitting for 20mins at whatever temp you want, Pull them out and boil as usual??.
 
Ok cool, I might try that. I just need to wait 12 months to get my oud bruin out of my glass carboys. I need a cellar!
 
...I tried around 4% flaked oats, and ended up with a very cloudy wort.

I don't suppose you've enjoyed the results just yet?

My brewing partner and I are having an extended debate on how to handle our next round of sours. I'm interested in this whole unconverted starch thing and he insists on adding simple sugars way down the line.

Normally we'd just split the batch into two 5g Carboys and do both, but not sure how to get those unconverted starches into only one half.

Looks we're doing like a double batch this week!
 
i wonder how important it is to steep/mash the oats/grains at a given temp, vs. just boiling them. it's not like you are converting the starches. you're just getting them out of the grain and into solution.

i recently did a split batch, based on jamil's oud bruin recipe. half is being soured as a flanders brown, the other half is on its way to becoming a BDSA (2 beers 1 brew!).

for the oud bruin half, i boiled up a mix of steel cut and flaked oats in a pot for 10 mins, strained, and poured the resulting oat-juice into the secondary along with the bugs. i'm not convinced that 180*F is any better, or worse, than a full boil. boiling takes less effort :mug:
 
i wonder how important it is to steep/mash the oats/grains at a given temp, vs. just boiling them. it's not like you are converting the starches. you're just getting them out of the grain and into solution.

i recently did a split batch, based on jamil's oud bruin recipe. half is being soured as a flanders brown, the other half is on its way to becoming a BDSA (2 beers 1 brew!).

for the oud bruin half, i boiled up a mix of steel cut and flaked oats in a pot for 10 mins, strained, and poured the resulting oat-juice into the secondary along with the bugs. i'm not convinced that 180*F is any better, or worse, than a full boil. boiling takes less effort :mug:

I'd be inclined to think that it doesn't matter that much. For me, it's super simple to just toss in a mesh bag of oats when it gets over 180F and take it out just before it boils. The overall idea is to get unconverted starch in to the beer for the brett and lacto to eat over time.
 
Yes, I think so.

Yep. Turbid mashing is a way to produce a starchy wort with barley and wheat. The Cantillon method is to basically do a few step mashes, and for each step you take a portion of the wort and boil it, adding it back in. Because of all the extra water used, you end up having to boil for like 6 hours... why do all that work when we can just steep some oats and not allow their starches to convert? :)
 
I'm following with interest.

I'm pleased with my sours, but would be interested in trying this to see if there is any significant difference (maybe it will end up too sour).

I'll be brewing a sour in a couple of weeks. Not sure whether to toss in a tablespoon of flour, or a cup of oats in the boil.

Anyone care to say why one may be better than the other? And, is that enough, it will be an 8 gallon batch.
 
I'm following with interest.

I'm pleased with my sours, but would be interested in trying this to see if there is any significant difference (maybe it will end up too sour).

I'll be brewing a sour in a couple of weeks. Not sure whether to toss in a tablespoon of flour, or a cup of oats in the boil.

Anyone care to say why one may be better than the other? And, is that enough, it will be an 8 gallon batch.

My thoughts is that it would be a bit funkier as the months/years go by, and probably not as sour (at least from the Brett breaking down the oats/flour). For example, I recently drank a 2012 and 2013 Cantillon Oude Gueuze. The 2012 was perhaps a bit more sour, but more over it was considerably funkier than the 2013.

I would also be interested in the difference between flour and oats. Perhaps one is easier than the other for the Brett to break down, which could cause some differences over time?
 
i believe that brett can't break down starch. the idea behind adding starch is that lacto and pedio can eat them, but brett can't. the bugs take a lot longer to do their thing, and while they get set up typically brett has already eaten all the sugars. so by adding some starch you're ensuring there is food left over for the bugs.
 
i believe that brett can't break down starch. the idea behind adding starch is that lacto and pedio can eat them, but brett can't. the bugs take a lot longer to do their thing, and while they get set up typically brett has already eaten all the sugars. so by adding some starch you're ensuring there is food left over for the bugs.

I can't claim to know much about this, but from what I've read I don't think that's true. For instance, in Wild Brews Jeff Sparrow says this:

Brettanomyces are superattenuating yeasts. They will continue to slowly consume sugars---even dextrins that are unfermentable to Saccharomyces---for many years. The behavior of superattenuation is attributed to, in part, the ability of beta-Glucosidase inherent in Brettanomyces to break down starch and dextrins and liberate glucose. (p.107)

Chad Yakobson also talks about this in these slides. If you go to page 6, he talks about beta-glucosidase being able to break down glycosidic compounds, which I think means starches.
 
Yeah, I've read a lot of posts on here saying that Lacto and Pedio break down the longer chain sugars and starches, but from what I have heard from Mike T and Chad Y, it's the Brett that does this. According to Chad, Brett is so strong that it can even break down cellulose (oak). Here are some talks Chad gave about just how aggressive Brett is:

https://www.youtube.com/watch?v=AjVOzBtE27Y
https://www.youtube.com/watch?v=Swv294Xkbq8

In addition, I've experienced and read about people who pitch Lacto later in secondary or at the same time as the primary yeast, and it always seems to result in not much sourness. Perhaps the Lacto is dieing due to the alcohol, and is too slow to consume the sugars, but in my experience Lacto eats the simple sugars just fine when it's by itself. That's why the method of pitching Lacto for 1 week before pitching Sacch in Berliner Weisse works so well for getting good sourness. If you pitch them together, in my experience the Sacch out competes the Lacto and consumes all of the simple sugars, leaving the Lacto with not enough food to make the beer sour enough. It's the same reason people use the method of pitching Lacto 4-7 days before they pitch Sacch in Berliner Weisse.

I don't know as much about Pedio, and need to do more reading, but I have read that Pedio contributes more sourness longer term than Lacto, which leads me to believe it can break down the more complex molecules. Anyone have more detailed information on Pedio in particular on this subject?
 
I don't know as much about Pedio, and need to do more reading, but I have read that Pedio contributes more sourness longer term than Lacto, which leads me to believe it can break down the more complex molecules. Anyone have more detailed information on Pedio in particular on this subject?

I'm curious about this too. Wild Brews just says that it ferments glucose into lactic acid.

Perhaps the reason pedio contributes more sourness in the long term is that it is more resilient. Lactobacillus stop reproducing at a ph of 3.8, whereas pedio can reproduce down to 3.4.
 
Good way to test this might be to do a regular 5 gallon type mash, steal a gallon for steeping oats, one for a half teaspoon of flour in the boil, one for nothing as a control, the rest with your preferred adjuncts and see what happens. I just might do this as my first single gallon experiments.
 
Good way to test this might be to do a regular 5 gallon type mash, steal a gallon for steeping oats, one for a half teaspoon of flour in the boil, one for nothing as a control, the rest with your preferred adjuncts and see what happens. I just might do this as my first single gallon experiments.

If you do, please let us know what happens in a year! :)
 
Here's something I'm unclear about.

Will flaked oats steeped in the kettle at 180F contribute any fermentables to the beer? Should I include them when calculating the OG of the recipe?
 
Here's something I'm unclear about.

Will flaked oats steeped in the kettle at 180F contribute any fermentables to the beer? Should I include them when calculating the OG of the recipe?

Eventually, yes, once the brett breaks the starches down into sugars and they are fermented by whatever is active in the wort at that point. I've no idea how to factor that into calculating the OG of the recipe though, and I don't know if starches in the wort contribute to its gravity at the start of fermentation?

But with the amount of oats we are talking about, the difference should be fairly small---a few points at most.
 
Eventually, yes, once the brett breaks the starches down into sugars and they are fermented by whatever is active in the wort at that point. I've no idea how to factor that into calculating the OG of the recipe though, and I don't know if starches in the wort contribute to its gravity at the start of fermentation?

But with the amount of oats we are talking about, the difference should be fairly small---a few points at most.

That's sort of what I was thinking. I'll list them as unfermentable for purposes of determining the post boil OG, knowing that the beer will finish lower since those starches will eventually be broken down.
 
I'm brewing a sour tomorrow. I'm going to try this. Worst that can happen is that it all drops to the bottom over the year+ of storage and makes no difference.

Questions I have are:

- What to add (flour, or oats, ...... or is there some other grain that might even be better; rice flour, buckwheat, millet, etc)?

- How much to add? I've seen a tablespoon of flour, and a cup of oats. Seems like a wide variation.

- When to add? Start of boil, near end of boil, at flame out?

Anyone any thoughts?

Without any further guidance/suggestions, I'm thinking of a couple of tablespoons of flour added to the boil about 10 minutes from the end.
 
I'm brewing a sour tomorrow. I'm going to try this. Worst that can happen is that it all drops to the bottom over the year+ of storage and makes no difference.



Questions I have are:



- What to add (flour, or oats, ...... or is there some other grain that might even be better; rice flour, buckwheat, millet, etc)?



- How much to add? I've seen a tablespoon of flour, and a cup of oats. Seems like a wide variation.



- When to add? Start of boil, near end of boil, at flame out?



Anyone any thoughts?



Without any further guidance/suggestions, I'm thinking of a couple of tablespoons of flour added to the boil about 10 minutes from the end.


I've used both oats and flaked wheat. My beers aren't done yet, but Flat Tail said they use oats. They also said to steep the oats at 180F when you're approaching the boil. They use a grant or something like that and I'm not quite sure what that is but he suggested using a strainer bag.

I don't recall them mentioning exactly how much to use, but I used 8oz for a 6 gallon batch.

.
 

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