Just a word about the Oats.
The worst possible choice would be "Quick Oats" they are often cut rather than rolled, which makes the starch less available. Rolled oats are fairly well gelatinised in processing but can still be less than fully available. Getting less from oats is a fairly common result.
I had a long hard look at this a couple of years ago while working on an ANZAC Biscuit recipe; this is where I ended up (yes got a beer that tasted like an ANZAC bickie).
1 Not all Oats are created equal.
Quick oats were the worst, selected for very high Glucan content, fine if you want to save 2 minutes at brekky time. Just not really all that good for brewing.
2 Rolled Oats, about what you would expect, good for porridge, fair for brewing...
3 Brewing Oats, surprise surprise the most expensive. Also worked the best. Selected for low gel forming so they don’t glug up your lauter but still give you all the things you are looking for in an Oat addition to your beer.
Making an ANZAC style beer I toasted my Oats to a golden brown and then "Digested" them.
That is mashed in about the same amount of milled malt and toasted oats at ambient (L:G ~ 3:1). Put a big pot on a small element on low heat so it rose in temperature very slowly (about 0.25 oC/Minute). This allowed all the enzymes to have a go on the way through to a simmer (100oC); mostly the Beta Glucan.
A 15 minute simmer meant the starch was also fully hydrated. The yield really was near theoretical and the mush was thin like a mash not like porridge at all.
If you want to use a cheaper alternative to proper brewing oats, at a minimum, use 2 volumes of water to 1 of oats and cook it like you would for breakfast. Best with some added malt. If you don’t want to add malt you really should do a Glucan rest around 46-49oC for 15 minutes or so as part of your mash regime.
Oats can bring a lot of nice silky mouth feel and body to a beer but they really are a bit of a PITA. It’s well worth using flaked Barley instead or even Flaked/Torrefied Wheat both bring a similar slickness and are easier to manage. If not quite as tasty.
Anyhow, have fun.
Mark
