A while back I was making a NEIPA and trying out Imperial's A38 Juice (it came out great by the way, very similar to my favorite Wyeast 1318 but slightly less sweet). On their website they said the yeast did best with higher DO levels of 20-25 PPM. From reading other experiments and other literature, I knew I needed to use bottled oxygen through a stone rather than my aquarium pump through a stone. My "process" for wort aeration has (had) been to just put the stone in the wort in the fermentor, and let it sit for 12-15 minutes when using my aquarium pump, and if I used bottled oxygen with its stone, I would let it sit for 3 minutes.
On the NEIPA I brewed, I used my new Milwaukee MW600 Dissolved Oxygen meter (hands on review here), and only read 8.1 ppm of DO after the 3 minutes of bottled oxygen through the aeration stone. I reached out to Imperial Yeast, and they were good enough to get back to me as we discussed my aeration process. After talking to Jess Caudill (Imperial's technical guy), the conclusion was I needed to "stir" my aeration wand/stone in the fermentor to get better oxygen levels. Even though I'm sure Jess is way more competent and experienced in the ways of yeast wrangling than me, I had a hard time believing that would make a difference.
So as a part of my review process of the MW600 meter, I set up a little experiment where I split my wort into 3 fermentors and then oxygenated them 3 ways. First was my aquarium pump that was left mainly stationary, other than shifting its position 3 times during an 18 minute aeration session. That got 7.1 ppm. Next was bottled oxygen and wand, with just putting the wand in the bottom of the fermentor and letting it sit for 3 minutes- 9.6 ppm. The last fermentor I used the bottled oxygen again for 3 minutes, but I continually moved the wand around in various directions continually- 19.6 ppm.
In hindsight I felt dumb to question the expert, but I just assumed everything was getting all mixed up with the stone on the bottom and bubbles rising to the top. Anyway, I thought I'd pass along this technique in case there were other out there unaware like I was.
On the NEIPA I brewed, I used my new Milwaukee MW600 Dissolved Oxygen meter (hands on review here), and only read 8.1 ppm of DO after the 3 minutes of bottled oxygen through the aeration stone. I reached out to Imperial Yeast, and they were good enough to get back to me as we discussed my aeration process. After talking to Jess Caudill (Imperial's technical guy), the conclusion was I needed to "stir" my aeration wand/stone in the fermentor to get better oxygen levels. Even though I'm sure Jess is way more competent and experienced in the ways of yeast wrangling than me, I had a hard time believing that would make a difference.
So as a part of my review process of the MW600 meter, I set up a little experiment where I split my wort into 3 fermentors and then oxygenated them 3 ways. First was my aquarium pump that was left mainly stationary, other than shifting its position 3 times during an 18 minute aeration session. That got 7.1 ppm. Next was bottled oxygen and wand, with just putting the wand in the bottom of the fermentor and letting it sit for 3 minutes- 9.6 ppm. The last fermentor I used the bottled oxygen again for 3 minutes, but I continually moved the wand around in various directions continually- 19.6 ppm.
In hindsight I felt dumb to question the expert, but I just assumed everything was getting all mixed up with the stone on the bottom and bubbles rising to the top. Anyway, I thought I'd pass along this technique in case there were other out there unaware like I was.