crushed oats, no cereal mash

[rhoop]

My wife has a flour mill so we have various whole grains sitting around the house. I made an oatmeal stout, which worked out very nicely if I may say so myself, and rather than use flaked oats, I ran some hulled oats through my barley crusher and threw them in my mash.

I have since learned about cereal mashes, and realized I should have done one to gelatinize the oats. In theory, because the oats were not gelatinized, the oat sugars would not have been fermentable, leading to a sweeter beer than I would have had, correct?

Or would the mash even been able to extract everything the crushed oats had to offer? My OG was a little low...

Can anyone clarify this whole gelatinization thing and it's effect on the mash for me?

 

[BigEd]

I have since learned about cereal mashes, and realized I should have done one to gelatinize the oats. In theory, because the oats were not gelatinized, the oat sugars would not have been fermentable, leading to a sweeter beer than I would have had, correct?

The sugar from the oats comes from their starches being converted in the mash. It is those starches that are and need to be gelatinizied, not the sugars since they have yet to be produced. That said you were probably OK since oats have a fairly low gelatination temperature although there may have not been enough time involved to fully complete the job.

Can anyone clarify this whole gelatinization thing and it's effect on the mash for me?

Mashing converts the starches into sugars. Enzymes need to be in an aqueous solution of the correct temperature and the starches need to be soluble to allow the enzymes to do their work. Gelatination is basically the hydrolyzing of a grain's starches so that they are made available for conversion in the mash by the enzymes. Malted grains and unmalted grains subjected to enough heat during processing (flaked grains and torrified wheat, for example) have already had their starches gelatinized. Raw grains such as your whole oats have not.

 

[Yooper]

The sugar from the oats comes from their starches being converted in the mash. It is those starches that are and need to be gelatinizied, not the sugars since they have yet to be produced. That said you were probably OK since oats have a fairly low gelatination temperature although there may have not been enough time involved to fully complete the job.





Mashing converts the starches into sugars. Enzymes need to be in an aqueous solution of the correct temperature and the starches need to be soluble to allow the enzymes to do their work. Gelatination is basically the hydrolyzing of a grain's starches so that they are made available for conversion in the mash by the enzymes. Malted grains and unmalted grains subjected to enough heat during processing (flaked grains and torrified wheat, for example) have already had their starches gelatinized. Raw grains such as your whole oats have not.

That's a great explanation!

Instead of a cereal mash, you could also simply cook the oats (make oatmeal) with them before adding them to the mash also. I often do a cereal mash if I have corn or rice, but rarely with just oats as my adjuncts. For oats that aren't flaked (like steel cut oats) I will often just cook them before using them.

 

[rhoop]

So if I'm understanding this correctly, gelatization essentially accomplishes the same thing malting does except through a different chemical process? Would you be able to "malt" oats?

 

[BigEd]

So if I'm understanding this correctly, gelatization essentially accomplishes the same thing malting does except through a different chemical process?

No, it does not. Gelatination is just a fancy term for getting the starches properly wet. Malting grain initiates the biochemical processes that yield enzymes and starch conversion. IMO the learning of these basic brewing terms and knowledge is greatly accelerated by having printed information on hand. If you do not own a good homebrewing book I strongly suggest buying one. John Palmer's "How to Brew" is generally agreed to be the best choice.

Would you be able to "malt" oats?

In theory, yes you could but it's probably a lot simpler to just buy them. Oat malt is available from many homebrew suppliers.