Lactose and FG estimate question

[Pelican521]

I know that lactose adds some gravity points but is there a way to figure how much?

I brewed an oatmeal stout 2 weeks ago and just checked the gravity. According to the brewing software, the OG should be 1.055 and the FG 1.014. I'm using brewtoad and it doesn't adjust for the for the lactose addition so I don't know what it really is after I added 3/4 lb.

My FG was 1.022 tonight. Does it sound like it could be finished fermenting?

 

[McCoy]

The potential of lactose is 35 points gallons per lb, multiplying by 3/4 lb and dividing by 5 gallons you get 5 points. I wouldn't be surprised if your FG came to about 1.022, especially if you're using extract and a low attenuating yeast. That said, you should always check your gravity twice over the course of a few days to make sure it's stable.

 

[Pelican521]

Thanks McCoy, I did use some DME, as it was a partial mash recipe. I was planning on racking to my secondary with 4 oz cacao nibs for two more weeks.

I was hoping to do this tomorrow and wanted to soak my nibs overnight in vodka, I'm wondering if I could go ahead and keep to my plan...

 

[McCoy]

I add cacao nibs directly to the primary. It's becoming popular these days to do most dry hop type additions in the primary, and secondaries are beginning to be regarded as unnecessary in almost all cases (notable exceptions seem to be lagering our other long term aging
and when the volume of the addition is large like when adding fruit).

To answer your actual question, there's no problem with sanitizing and adding the nibs now.you don't really need to be at FG to do that, although it is a good idea to at least wait until vigorous fermentation is done so the aromatics don't get pushed out the airlock.