Amount of base malt to convert adjuncts?
 

I understand, from "How to Brew", that many adjuncts (I'm especially thinking oatmeal here, for a porter) require mashing with an enzymatic base malt to become fermentable. My question is, what's an appropriate ratio of base malt to oatmeal, given that I'm only doing a partial mash rather than an all-grain batch? I don't recall seeing this info anywhere; if there's an online calculator or guide somewhere, link away...

I'd go a pound of base for a pound of oatmeal or rye. And it's always a good idea to precook/boil oatmeal before adding it to the mash.

Are you doing all grain or partial mash? If your adjuncts don't go over 10% (and why would they?) you should be fine. If you're extra-paranoid, you can add some amylase to the mash.

-----edit-------
well, if i would've read your post carefully, I would have seen that you're doing a partial mash. so listen to the others who read your post more carefully :) i need some sleep. good night cruel world!

1 to 1 ratio. Just match all your specialty malts and adjuncts pound for pounnd with a base malt. Even more base malt won't hurt. If your total grain bill is less than 3 pounds, add base malt to reach 3 pounds. This helps with heat retention and filtering in the mini-mash.

For what it's worth, 6 row has greater enzymatic power than 2 row. While some say the 6 row will lend more of a grainy taste I've never noticed it (though I do usually stick with 2 row anyway). Anyhow, if you're concerned then you could try using 6 row base malt.

I wouldn't go above 20% fermentible adjuncts. (Source: Papazian - The new complete joy of home brewing),

Assuming you flaked oats, they should not need precooking as they were cooked during the flaking process (Numerous sources including Papazian).

Good luck.

-a.

peatreek, try www.promash.com. it's a very good brewing software that you can down load a free sample or order it on-line. almost any HBS will have the software too ($25). ifyou download the trial version, it will let you save three recipes. or, you can use it to calculate, write it down, then just don't save it and you can use it over and over. helps w/ water calculations, grain bill, IBU's, etc. i love it!