I am prepping to make a mini-mash Biere de Garde this weekend and I will be using a new fermenter which increases my volume from 5L to 2 Gallons (roughly 7.5L). I increased my grain/hops without considering that I might need more than 1 Wyeast pack. OG is supposed to be 1.067, ABV 6.34. My yeast has a date of 2/16 (which is a bit older than I'm used to from this supplier). Mr Malty says I'll need 1.2 packets w/o a starter. For various reasons I'd prefer not to do a starter. As I see it I can 1) Underpitch by about 12% 2) Reduce OG to 1.059 by reducing DME addition and keeping volume the same. ABV=5.57% 3) Reduce batch volume to 7L and OG would then be 1.064, ABV 6.05% Thoughts? Comments? Advice? Right now I am leaning toward option 3. Thanks!
I think you might be fine under pitching, but I'll also state that as a professional brewer I always over-pitched. I'm not sure why you wouldn't have just done a starter though, you could have had it going already.
I think you can somewhat ameliorate the effects of an underpitch with good oxygenation. I would shake the fermenter more vigorously or longer than usual, just generally try to get a lot of oxygen in there. But in truth, what I would really do is relax, don't worry, have a homebrew, because a 12% underpitch wouldn't concern me much at all. I guess I would make a little more effort than usual to get every last bit of yeast out of the package, rinse it with pre-boiled (and then cooled) water or whatever, to get those last few hundred million cells out.
I agree with the above, that is not a significant underpitch from my experience and I have never noticed anything notable. The yeast will have to work a little harder, but it's the least they can do for the free meal.
