When to Add LME and Dextrose to Boost Gravity in an Imperial Stout

[philm63]

I'm limited to what'll fit in my 10-gallon vessels in my eHERMS setup and I'm looking to brew an Imperial Stout. I can comfortably mash grain for most of the gravity points I need (want) and will use LME and some dextrose for the remaining gravity points. I've worked it all out and am happy with the recipe, so my only question is when to add the LME and sugar - before I start the boil, at flameout, somewhere in between...?

I can calculate the hop additions to work out any which way, but it seems to me I can boil for a shorter time if I add the sugar and LME at the front-end and end with the same OG as I would if I added the sugar and LME at the end of a longer boil. For a stout, is there any risk to adding the LME and sugar at the beginning?

 

[lumpher]

No, there is not. I've made many LME (and DME) Stouts over the years, and added all the extract at the beginning.

 

[DBhomebrew]

Adding the extract late will preserve its light color and increase hop utilization. Color is obviously not an issue here. Your recipe software should account for the hop utilization.

 

[RM-MN]

Just a wild thought going through my head. Hold off adding the LME until day 2 or 3 of fermentation. Let the yeast build up in a lower gravity beer first, then with plenty of yeast in the beer, feed them some more sugars. Watch for explosive fermentation.