Flaked grains - Best practices

[Jogurt]

I have several questions regarding flaked grains - be it oats, wheat or others.

I apologize, because I have surely been answered elsewhere, but the information seems scattered and somewhat contradictory.

People here tend to differentiate multiple versions, but where I live, we simply say "flaked oats", "flaked wheat" etc. So I am posting pictures to be sure, that we speak about the same thing.
Wheat
Oats

I ask these questions, because I plan on brewing a beer with 50% flaked grain, so I want to know, what to expect.

1. Is it possible to substitute unmalted grain with its flaked version?
For instance, I want to brew an authentic Witbier. Will there be any difference in result?

2. Mash or steep?
Some people say they need to be mashed, some say they need to be steeped, some say that steep will do, but needs to be an hour long (uh?).
So what is your experience with this? Do you need a base malt with good diastatic power to convert, or not? And if yes, how much?

3. How do they affect lautering?
In one of my oatmeal stouts, I decided to try steeping the oatmeal. However I did not mix it in the grain and then transfer to lautering tun.
Instead I put the dry oat flakes on the bottom and transfered the mash on top of that. It resulted in my worst lautering ever.

Later my friends told me, that I should have used the flakes along the other grains, when mashing in.

So what is your experience with brewing with flakes? What are the best practices? Any useful articles, further reading out there?
Thanks for help.

 

[alane1]

1) Flaked grains are gelatinized so they are usually used to provide mouthfeel, substituting flaked for unmalted will produce a very different result.

2) Flaked grains need to be mashed with grains with diastic power. they won't convert by themselves.

3) They could create a difficult runoff, I wouldn't use flaked grains in excess of 20%

 

[lpdjshaw]

Put the flaked grain on top of your mash for easier lautering

 

[helibrewer]

Unmalted whole grain needs to be crushed and cereal mashed in order to gelatinize it. As stated above, flaked products are already gelatinized and go in the mash.

They will effect lautering because they are very high in B-glucan and proteins.

 

[tootal]

Rice Hulls are your friends. Put a lb. of hulls in if your using over 10% flakes. They don't add any flavor, just a way for the wort to get around all the goo!

 

[brettwasbtd]

Rice hulls definitely can't hurt. I just did a wit this past weekend which was a 50/50 split of pilsner and flaked wheat with no rice hulls and had no difficulties. Some of it depends on your setup (I have a cpvc manifold in a cooler) and some of it depends on your crush - intact grain husks help act as a filter. For what it's worth I have used malted wheat in this same recipe with crowd pleasing results

 

[IslandLizard]

Like Brett said, using rice hulls in the mash definitely helps lautering. You can go as high as 50% (or 70% or even higher) with "flaked" adjuncts as long as the average diastatic power of all the grains in the mash that need conversion is above 35-40L. Pay attention to how the DP was derived, there are different ways to measure or calculate. When in doubt you can do a small test mash. You may need a longer mash time if the DP is borderline. An Iodine test can confirm complete conversion.

I mill all rolled and flaked adjuncts at a relatively narrow gap setting, 0.025-0.028" to allow quick and thorough hydration when mashing in. Just adding rolled adjuncts whole make no sense. Some finely flaked varieties (e.g., instant oats) are very thin and may work as they are, but I'd run everything through the mill anyway.

If you mash in a bag you may have fewer lautering problems, and not need rice hulls, but that bag needs to be squeezed well as the mash inside is just as gooey. I just prefer batch lautering and sparging with a manifold.

 

[RonPopeil]

Skip rice hulls and buy a BIAB nylon. Order your wheat/oat seperate and pour into the BIAB nylon. Or just mash the whole thing in the nylon. Makes life way easier.

 

[dobe12]

1) Flaked grains are gelatinized so they are usually used to provide mouthfeel, substituting flaked for unmalted will produce a very different result.

2) Flaked grains need to be mashed with grains with diastic power. they won't convert by themselves.

3) They could create a difficult runoff, I wouldn't use flaked grains in excess of 20%

This ^^^.

I used flaked wheat, oaks, and rye quite often and really like what they add. Flaked is the way to go since they need to be mashed, but do NOT need to be cereal mashed. When making something like a wheat beer or Wit, I find flaked wheat is needed to get that true wheat flavor and appearance.

I'll also 2nd the BIAB suggestion above.

 

[IslandLizard]

Skip rice hulls and buy a BIAB nylon. Order your wheat/oat seperate and pour into the BIAB nylon. Or just mash the whole thing in the nylon. Makes life way easier.

You do have to add enough diastatic malt to that bag of flakes or nothing good will happen. And the more grains with hulls you add, the easier it is to get the wort out of the gluey grain mass.

 

[RonPopeil]

From what I understand, conversion enzymes are in liquid wort. That's why you strain liquid wort off when you pull decoctions. Prevents denaturing. Being the case, It shouldn't matter if the adjuncts make direct contact with barley or not as the enzyme is suspended in the liquid permeating the bag.

I've used this method a couple of times and haven't had issues with wort volumes or efficiency.

 

[IslandLizard]

Agreed on a large percentage of the enzymes being in the liquid phase of the mash, there's also a significant amount located in the thicker part, adsorbed to the swollen grain bits.

As long as you can get wort to penetrate well inside the bag filled with flaked matter the enzymes should be able to do their work. In that scenario I expect some agitation is needed throughout the mash period. I tend to think more homogenous mashes should return better efficiency, while agitation is less needed.

Hanging a bag with 5 pounds of flaked adjuncts inside a mash tun will be a poor performer.

 

[RonPopeil]

Agreed on a large percentage of the enzymes being in the liquid phase of the mash, there's also a significant amount located in the thicker part, adsorbed to the swollen grain bits.

As long as you can get wort to penetrate well inside the bag filled with flaked matter the enzymes should be able to do their work. In that scenario I expect some agitation is needed throughout the mash period. I tend to think more homogenous mashes should return better efficiency, while agitation is less needed.

Hanging a bag with 5 pounds of flaked adjuncts inside a mash tun will be a poor performer.

I just toss the whole bag in and let it sink. Fish it out after I drain the mash tun. I do poke the bag around a bit with my giant metal spoon to make sure everything gets wet. That's just common sense though. You do the same thing without a bag to break up dough balls.

 

[IslandLizard]

I just toss the whole bag in and let it sink. Fish it out after I drain the mash tun. I do poke the bag around a bit with my giant metal spoon to make sure everything gets wet. That's just common sense though. You do the same thing without a bag to break up dough balls.

Not to argue, but I doubt you're getting all that much out of the flaked grains in the bag that way. Sounds like it may form a huge sticky porridge dough ball. Only you can gauge how efficient that method is.

 

[RonPopeil]

Not to argue, but I doubt you're getting all that much out of the flaked grains in the bag that way. Sounds like it may form a huge sticky porridge dough ball. Only you can gauge how efficient that method is.

No worries man, everyone has their opinions. Using this method and setting the flaked grains to "Mashed" in software, I hit my gravity numbers. I admit that when it comes to understanding sugar conversion and exactly what goes on in the mash tun I'm not the most knowledgeable. There probably is a better way to do it. The only thing I can say is that it seems to work or that it works as well as it's expected to work. The main benefit is no extra money spent on rice hulls and easy clean up of the mash tun.

If you or someone else would like to bring the science into it I'm all ears

 

[stronk]

Anyone suggested a beta-glucan rest yet? This and other rests tackling proteins will probably help your efficiency (including both conversion and sparging) if you are using lots of sticky wheat. Even if you're using BIAB and not sparging, you'll probably get lower efficiency if everything is really sticky.

It does mean doing a step mash, which is a bit of a pain. But someone above has already suggested decoction. If you're doing this, then you've got yourself a method to control the temperature, rather than just doing a single-step infusion at a certain temperature.

See explanation of various enzymes and mashing steps here:

http://www.howtobrew.com/section3/chapter16-2.html
http://www.howtobrew.com/section3/chapter14-1.html

 

[dobe12]

The OP started off asking about flaked grains. Now we have him doing decoctions adding hours to his brew day.

Gotta love HBT