Advice/questions for my Imperial Stout brewday tomorrow

[TBC27]

Hi All. Looking for some advice/answers for an imperial stout I’m brewing tomorrow. Here is a link to the recipe - https://www.homebrewersassociation.org/homebrew-recipe/kaos-returns-imperial-stout/ . You need to be an AHA member to view this, I believe. If true, I attached a screen shot of my grain bill below.

1. When should I add the DME and brown sugar to the boil? Normally I add sugars towards the end of the boil for Belgians and IIPAs. 15 minute mark?
2. If I fall short of my OG, can I add more DME to boost gravity? When and how do I do that since I don’t measure OG until after cooling the wort?
3. I read somewhere that it is a good idea to hit the wort with a second round of oxygen 12 hours post pitch. Anyone do this and is it recommended?

 

[RM-MN]

1. When should I add the DME and brown sugar to the boil? Normally I add sugars towards the end of the boil for Belgians and IIPAs. 15 minute mark?
2. If I fall short of my OG, can I add more DME to boost gravity? When and how do I do that since I don’t measure OG until after cooling the wort?

It doesn't matter much when you add the DME and sugar. If this was a light colored beer you would want to add the extract at the end of the boil to prevent some darkening but for a stout?? As long as the wort is still above about 145 degrees it will be pasteurized.

Adding DME to boost gravity is a decent idea. I'd dissolve it into a bit of boiling water first and then add the mixture.

 

[HTH1975]

If you add DME and sugar at the end of the boil, you will get slightly better hop utilisation too. I’d maybe just take off a litre or so of wort, then dissolve the sugar and DME in it before adding to the main boil.