Brewed up 5 gal of this recipe tonight (after brewing 5 gal of bitter this afternoon). I went with this recipe:
0,50 kg Grits (1,0 SRM) Adjunct 12,50 %
3,00 kg Pale Malt (2 Row) US (2,0 SRM) Grain 75,00 %
0,30 kg Rice, Flaked (1,0 SRM) Grain 7,50 %
25,00 gm Goldings, US [3,90 %] (60 min) Hops 15,3 IBU
10,00 gm Goldings, US [3,90 %] (30 min) Hops 3,1 IBU
0,20 kg Sugar, Table (Sucrose) (1,0 SRM) Sugar 5,00 %
I tried a little experiment. After reading on the gelatinization temperatures of the corn grits, I found that it was in the range of the sacch rest. So what did I do ? I skipped the cereal mash and just did a single rest @ 151F for 90 minutes.
Since I hit the OG right on the nose (and thus got complete conversion), I don't think a cereal mash is absolutely necessary for grits, provided you mash for a long enough time in the right range.