A very dark, full-bodied, roasty, malty ale with a complementary oatmeal flavor.
Generally between sweet and dry stouts in sweetness. Variations exist, from fairly sweet to quite dry. The level of bitterness also varies, as does the oatmeal impression. Light use of oatmeal may give a certain silkiness of body and richness of flavor, while heavy use of oatmeal can be fairly intense in flavor with an almost oily mouthfeel. When judging, allow for differences in interpretation.
Samuel Smith Oatmeal Stout, Young's Oatmeal Stout, McAuslan Oatmeal Stout, Maclay's Oat Malt Stout, Broughton Kinmount Willie Oatmeal Stout, Anderson Valley Barney Flats Oatmeal Stout, Tröegs Oatmeal Stout, New Holland The Poet, Goose Island Oatmeal Stout, Wolaver's Oatmeal Stout
You can view the complete style details on the BJCP website. The 2008 style guide is obsolete but there is a similar 2015 style that you can view below...