Nutz!

Grape Nuts cereal? As an adjunct? The heck you say‽‽‽
Heck yes! I do say!

Here's the recipe. Inspired by this ancient article in BYO.

Mash
4.5 gallons 163.0° F strike water dechlorinated with 1/2 campden tablet (potassium metabisulfite).

Grain bill:
8 lbs. Breiss American 2-row
3 lbs. Post Grape Nuts Cereal
8.25 oz. American Crystal Malt 60-lovibond
1 oz. British Black Patent Malt
1/2 lb. Rice Hulls (a precaution to prevent a stuck sparge)

Temperature Management
Boiled 4 1/2 gallons of water on Brew Day Eve. Transferred this at near-boiling temperature to the mash tun around midnight and let it sit overnight. 8:30 the next morning the temp in the tun was 109F. Not bad. I was hoping for better.

Dough-in occurred at 9:55 a.m. mash temperature = 150.5° F. Perfect! 1 hour later the temperature in the mash tun was 146°. Again, I was hoping for better.

Next time I'll boil 6 full gallons of water the night before and transfer all six gallons to the tun. On Brew Day, I'll take 4.5 gallons back to the HLT and leave the remainder in the tun until the strike water has been re-heated. Finally I'll drain the mash tun just before draining the full contents of the HLT to the tun one final time. Also I'll be more patient about waiting for the liquor to fall to strike temp. This time I kept recirculating 1 gallon at a time out through the spigot into a pitcher and back into the tun again until I got within a few degrees. Next time I'll stop this process when I'm within 10 degrees of my target strike temp, or even farther.

Sparge
Good thing I included those rice hulls. I've never had a stuck sparge since I started AG brewing about a year ago, probably because I batch sparge. This was the closest I've ever come to a true stuck sparge. Runoff was painfully slow. If I ever get silly and brew with Grape Nuts again, I'll definitely use rice hulls. Perhaps a whole pound of them.

Boil
Hop Additions
1.5 oz. of Tettnanger 6.1% alpha acids @ 45 min
.5 oz. of Tettnanger 6.1% alpha acids @15 min
Irish Moss @ 15 min.
O.G. = 1.050

Fermentation
Pitched directly onto the Surly Furious Clone yeast cake.

Primary fermentation was held at 60°F for the first week. On Tuesday 11/6/2012 (nothing else of import happened that day, except I hear that Halo 4 was released) there was still a good inch of kraeusen on top of the beer. Specific Gravity reading was 1.018. Almost done. Tastes like Grape Nuts, in a good way. A little sweet. Slightly salty--which adds to the interestingness of this experimental brew.

On Thursday 11/8/2012 the primary fermenter was moved to a 69°F environment in hopes that the warmer temperature will stimulate the yeast to finish their job. Hopefully the final product will have an FG of < 1.015. 

Finishing, Bottling, and Drinking
Bottled on 11/18/2012. FG = 1.013-1.014; the extra week at warmer temps did the trick. Used 4 oz. of dextrose dissolved in 2 cups of pasteurized water in a pasteurized Pyrex measuring cup. Bottled directly from primary

Tasting notes:
Christine, having been given a room-temperature un-carbonated sample on bottling day, without any inkling of what she was drinking, said, "A mild sweet red ale. Sweet but not too heavy. It has a little bit of berry-ness to it without being a particular berry, maybe like a strawberry. It's like Pi Common meets an un-hopped Surly Furious Lite."

Knowing what I was drinking made it impossible for me to be as objective as possible. Knowing how much salt they put in Grape Nuts cereal makes me extra sensitive to the saltiness of the finished product. I know I should be pleased that it was able to ferment at all with so much salt in it. And I'm not displeased. It's just that the saltiness is the first and last thing I notice in every sip. The fact that Christine, tasting blindly, didn't seem to notice this flaw is heartening.

That said, the finished beer really does taste like Grape Nuts. This is obviously what I was going for, and the flavor is not out of place in a malt-forward brew such as this. There is more hoppiness here than in, say, a Scottish beer or an English brown or porter/stout, but not too much more. Much less hop flavor than in an American pale ale certainly.

Note to self: do not brew this exact recipe again. For that matter, do not use 3 whole lbs. of Grape Nuts in any future 5-gallon batches.

In the future I will not rule out Grape Nuts as an adjunct if I'm looking for the specific flavor profile it imparts. I will limit the amount I use to 1-1.5 pounds/5 gallons of finished beer. This should make the distracting saltiness practically disappear. Whether or not the delicious grapey-nutty flavor from so many weekday breakfasts of my childhood will still show up at that lower concentration will have to wait to be seen.