Late addition to the fermentation

[MinnMoose]

I am making an oatmeal stout recipe called grandma's hidden stash. The recipe calls for rum soaked raisins, which I initially added. When I transferred it into the carboy for fermentation, I was having all sorts of problems with the raisins getting stuck in the hose and the spigot on the bucket, so I just siphoned the rest, leaving behind the sludge in the bottom, and the raisins. This didn't occur to me until later, so after about 36 hours I added some more rum soaked raisins, being careful to sanitize everything. I noticed that after the addition, the foam on top almost completely disappeared. The beer is still very active and bubbling like crazy. Still, I'm wondering if I might have done any damage to the beer by adding later into the fermentation?

 

[McKnuckle]

You fermented in a bucket for primary and had raisins in there, then transferred to a carboy as a secondary vessel - right? And when you did that, the raisins didn't transfer, so you added more. Just trying to clarify.

Normally, one adds fruit or other solids to the secondary vessel, not the primary. Not that it's necessarily an issue, but one purpose of transferring from primary to secondary is to leave sediment behind. The raisins, being solid, would settle to the bottom - along with trub and gunk - so you can see how this is a self-defeating technique.

As for adding more raisins a day later to the secondary, no big deal. They are full of sugar, which the yeast will happily dispense with regardless of when they are added. Now, just leave it be for a while and late nature take its course.

 

[ReaperOnefour]

Whats up Dave? I agree with McKnuckle. You would usually add the raisins in secondary, but it's cool. No harm done. As long as you properly sanitize everything, im sure the beer will come out great. Happy Brewing, & welcome to the forum.

 

[RPh_Guy]

The raisins, being solid, would settle to the bottom

Raisins float.
It takes months for them to sink. Or maybe a few cold crash cycles.

 

[Abhishek Dewan]

If you add a shot or two of vodka to a fermenter, you will notice no Krausen or foam and hence no blow offs. Something to do with surface tension and it doesn’t negatively impact fermentation. The rum soaked raisins might have had the same impact, depending upon how much liquor was in them.

 

[MinnMoose]

Thanks for the comments everyone.
An update on the beer. It has started to calm down a bit now. It has probably been the most active beer that I've made so far. Even with a blow off hose, it still blew off the bung about 18 hours in. The raisins are floating and everything else seems to be starting to settle nicely. It's a little lighter in color than I expected for a stout.
To answer a couple of questions,
First the rum soaked raisins are specifically supposed to go in the primary (according to the recipe anyway), and rum soaked vanilla beans will be going into the secondary.
Secondly, the reason I was transferring the beer from a bucket to the carboy was only because I had been pouring the beer between two buckets to aerate it after adding the yeast. This was a method that an instructor used in one of the homebrewing classes I attended.