All Oat Bitter/Keptinis

Plan is to bake portions of the mash (like the keptinis descriped here: http://www.garshol.priv.no/blog/394.html) to achieve a darker wort and more complex flavor.


-----------------------------------------------------

Some results and lessons learned:

1. While the mash converted, eventually, as evidenced by an iodine test, I have the feeling it was mostly larger unfermentable dextrines. While the wort was sweet, it definitely wasn't as sweet as I would have expected. When I baked the mash I got plenty of browning, some burning, but little actual caramelization - my Chemistry-fu is weak (something I should correct one of these days), but that seems like it would be indicative of more maillard reactions than caramelization. Finally, the Voss I pitched (@102f, held at 95f for the duration) chewed through the wort to 1.020 in just a few hours (lag time was maybe 45m), and then stuck there solidly. Next time, mashing with some glucoamylase alongside the alpha amylase might be in order. If only I could find some enzymatic oat malt...
   
   
2. In retrospect, a step mash would probably be appropriate here; the oat malt is almost certainly under modified, and dealing with some of the beta-glucans would be a good idea. Next time, maybe rests at 113 and 122 would be a good idea?
   
   
3. When baking the mash, I preheated the oven to 500f (with several baking stones on the bottom for thermal mass), before turning it down to 380f with convection right as I put the mash in. The mash itself was split between two aluminum roasting pans, a pyrex baking bowl, and a cookie tray, and baked for about two hours. While the mash in the roasting pans thickened and browned nicely, albeit with less caramelization than I had hoped for, the cookie tray just burned and the baking bowl remained fairly liquid inside. Roasting pans all the way next time.
   
   
4. Next time I need to remember to allow the yeast more time to clean up; by the time I check the next morning, after brew day, this had already reached it's terminal gravity of 1.020, so I allowed it 24 hours to make sure it wasn't going to move, and then cold crashed. That was almost certainly too fast, even for kviek.
   
   
5. Results: the pre-carb sample I pulled, after closed transfer to a serving keg, wasn't bad. The beer evidenced some harsh burnt toast flavors, but it seemed like it would be drinkable, especially after a little bit of mellowing with age. After a few days force carbing though, it developed a highly medicinal, hard to describe, backtaste - perhaps the carbonation just made some compounds (phenols?) more accessible to taste, or maybe I got an infection during the transfer or in the new keg? I'm going to let this keg hang around at room temperature for a few weeks before tossing it, on the off chance those flavors clear up, but I don't have high hopes.