I was about to buy some quick oats for a white IPA and realized I have a big Costco bag of old fashioned oats. Is there any reason I couldn’t just use the old fashioned oats? Should I mill them? Or should I just buy some quick oats?
You don’t need to mill them, but you do need to precook them to gelatine the starches and make them available for conversion.
Why? AFAIK, they are steamed when they are rolled, the same as quick oats. I thought that gelatinized the starches. I’d thought the only difference between quick oats and old fashioned oats was that the quick ones were chopped up and the old fashioned oats were intact. But I guess I won’t chance it and will just buy some quick oats.
I have used old fashioned oats without cooking them and have had no problems with conversion. I think Denny may be thinking of steel cut oats.
Old fashioned oats are rolled but not steamed or not completely steamed like quick oats. If the directions on the bag say to cook for under three minutes, they’ve been steamed enough it’s no problem. If the directions call for a longer period, they may benefit from cooking them before mashing them. You’ll find lots of homebrewers use old fashioned oats and do not pre-cook them. Just depends on how much you care about reaching full conversion from your oats.
Don’t need to cook old fashioned oats. Just mix with your other grains. I have used up to 25% old fashioned oats in the grain bill no problem with no rice hulls or pre cooking.