Crystal malt with oats?

[CHansen6]

I've been playing with the idea of some 100% oat beers, but there really isn't a lot of variety out there. I can't really find anything other that malted, flaked, and golden naked oats. Golden naked oats look to be a light crystal depending on who you ask, or at least is often listed as a light crystal.

I was wondering if anyone has ever tried to make caramel malt out of malted oats? I've read plenty on brewers toasting flaked oats or occasionally oat malt for more of that oatmeal cookie type flavor. I was hoping to introduce more color and more darker caramel flavors.

The process doesn't seem too hard. Hydrate grains, rest at mash temperatures to liberate sugars, roast/caramelize the sugars, and rest for a few weeks to mellow.

This thread is about as close as I've seen, but still doesn't offer much information. https://www.homebrewtalk.com/showthread.php?t=245101&page=3

 

[Homercidal]

I don't think oats have any diastatic power, so you will need to find a way to covert their starches. I think there are maybe some additives that can help with that.

 

[CHansen6]

I've read very conflicting information about that. Several homebrew suppliers list the diastatic power at 0 lintner, but that doesn't mesh with the reports of a handful of 100% oat beers I've seen. There is even a paper from the Journal of the Institute of Brewing on making 100% oat malt. It lists the amount of alpha amylase 25DU vs. 50DU for a Sebastian barley (pale I presume). Further digging shows that sebastian barley has a diastatic power of 92L (307WK).

Oats clearly have alpha amylase, and presumably other enzymes important for starch conversion. If you assume that the diastatic power scales approximately with alpha amylase content, that would put malted oats right around 46L. That is far from a perfect approximation. Ball park, it puts oats right on the edge of full conversion capabilities though. This is consistent with some of the accounts of 100% oat beers I've read about. Most notably that long mash times are suggested, which would be consistent with a borderline amount of enzymes.

You're right though, it'd probably be a good idea to include some barley or extra enzymes to help out. Adding caramelized, roasted, flaked, etc. oats will just put you more downhill. That's kind of a side point though. If I can't make a 100% oat beer, that's fine. However, I'm still interested in seeing if anyone has tried to convert oats into caramel oat or roasted oat type of grains.

http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.2011.tb00487.x/epdf
http://onlinelibrary.wiley.com/doi/10.1002/star.201300152/pdf

 

[Homercidal]

Amylase Enzyme is easily had, and won't affect the flavor in the same way that a portion of malt would. It's a curious experiment. I've never heard of a 100% oat beer.

 

[BrewerinBR]

The study in the link indicates that 100% Malted Oat Beer is possible. Need to deal with two factors A) the lipid (fat) content of malted oats is almost twice as high as malted barley and B) proteins are higher so you may not be able to get clarity and the beer may be a little "chewy". If you want to add a caramel flavor you can add caramelized sugar which would help to counteract some of the "chewyness". I have toasted oat meal in oven for brewing but never used straight malted oats. They are available. You could try roasting a lb and add that for roasted flavor.

http://waset.org/publications/7906/optimization-of-enzymatic-activities-in-malting-of-oat

EDIT: Located another study that is even more informative for the brewer!
http://onlinelibrary.wiley.com/doi/10.1002/j.2050-0416.2011.tb00487.x/pdf

 

[CHansen6]

It seems grains high in oats were popular during the medieval times for cost reasons. Apparently 100% oat beers are not all that interesting on their own, thus my interest in roasting the grains. Very oaty and grainy, but somewhat delicate from what I've read, which really isn't surprising. There are also prone to residual sweetness, and weird mouthfeel if you don't mash them right. Those often had flaked oats or golden naked oats, which might not be totally converted from the malted oats and leave a viscous sweet beer. I included a couple of links in case you or anyone else is interested.

By the way, I found at least one mention of caramel and roasted oat grains. It seems like they're a one off, but at least doable. http://valleymalt.com/maltofthemonth/

http://ryanbrews.blogspot.com/2009/12/100-oat-malt-mt-rainier-hops-smash-beer.html
https://kenanddot.wordpress.com/2012/12/02/100-oat-malt-beer/
http://www.thebrewingnetwork.com/forum/viewtopic.php?f=&t=27346
https://www.homebrewtalk.com/showthread.php?t=536635
https://www.homebrewtalk.com/showthread.php?t=536635

Something very different, but interesting.
https://books.google.com/books?id=X2lHAAAAYAAJ&q=Oat+Ale#v=snippet&q=Oat Ale&f=false