[ccfoo242]

I completely forgot to add yeast nutrient to my starter and wort.  It's been in the fermenter for 24 hours now. Is it too late to add any? The OG was 1.078.

[edit]
It is actively fermenting...

[bluesman]

I usually add it during the last ten minutes of the boil, and you can also add it pior to fermentation, although I wouldn't worry about it at this juncture, because the yeast consumes most of the nutrients during the lag phase which is typically during the first 12 to 24hr of the fermentation schedule.

[Hokerer]

I've always wondered about the sanitation aspects of not boiling the nutrient.  Always been afraid to mess with it post-boil.

[jlap]

I think yeast nutrient is clean enough to add without boiling.  Adding at the 1/3 and 2/3 sugar breaks is a very common technique in wine, mead, and cider.  I think you'd be fine doing it now although you may want to dissolve it a little in some clean water before adding it to avoid nucleation - been there done that. 

[richardt]

I add Fermax (DAP, DPP, MgSO4, autolyzed yeast) to the starter wort (extra-light DME) and a few drops of FermCap-S.  I tend not to add the nutrients to the boil kettle or the fermenter.  IMO, the key lag phase I'm interested in is when the yeast are in the starter flask. 

[ccfoo242]

Well I went ahead and boiled a cup of water, mixed in the nutrient then cooled and threw it in the fermenter. I probably did enough wrong that it will taste like crap anyway, so I figured it wouldn't hurt.

[richardt]

When would the yeast benefit most from the yeast nutrient? 
I think the answer would be: In the starter.
Yeast can spend time utilizing the nutrients towards cell growth before they get pitched into your wort.

[jlap]

I guess my point is that they also benefit as the alcohol level builds in the fermentation and the nutrients needed for metabolism are depleted.  I suspect that in lagers, as in wine, proper nutrient levels could help limit sulfur production late in the fermentation as well as ensure full attenuation.  One of the potential problems of adding nutrient to the boil is that any wild yeast or bacteria that have not yet been out-competed by the brewer's yeast also get the benefit of the nutrient.  Obviously this is more of a concern with wine/mead/cider where there hasn't been a boil.  All I'm saying is that there's more than one way to slice this...