Hi guys. I'm having a tough time with this yeast and am trying to figure out what's going wrong. Over the past year I purchased three PurePitch packages from two reputable retailers. All three packages had different manufacture dates, and all had at least two months remaining until their respective "best by" dates when I used them. As far as I know, all had been refrigerated properly in storage.
My plan was to do a couple of bitters and a brown. All recipes were in the 1.050-60 (OG) range.
For each of these, JZ's pitch-rate calculator suggested making around a 2L starter, so I did that with DME (1.040) and a pinch of urea/DAP. I did the starters in an Erlenmeyer flask on a stir plate. Sanitized aluminum foil cover. Pitched yeast into starter at 70F and stirred for 18 hours. Stopped the stir and let the starter remain at 70F for another 24 hours to build up glycogen reserves. Placed flask in refrigerator overnight to cool.
In all three cases, there was never any krausen that formed in the starter. I thought this to be odd. Plenty of CO2 bubbles, though. After cooling overnight in the refrigerator, there was far less healthy yeast than I'd expect to see at the bottom of the flask. And what was there was quite powdery. There was also quite a bit of brown, dead yeast.
I probably should have run these through another starter stage, but I didn't. Pitched into my primary wort. Just like with the starters, there was no krausen whatsoever during fermentation. A lot of CO2 bubbles, but only after a relatively long (48-hour) lag phase. I don't think there was any problem with my fermentables. The beers all under-attenuated (1.020-ish FG) and there wasn't much live yeast in the trub.
I didn't do these sequentially. I brewed other batches with different yeasts in between, and didn't have any problems with those. It's only when I used WLP023.
I keep reading about what a good top-cropper WLP023 is, so I'm not sure why I'm consistently seeing this behavior from it. I'm obviously under-pitching, but I don't understand why I can't even get decent growth in a starter. Wonder if this particular strain has a short shelf life. Or perhaps my three packages were mishandled in some way before I purchased them.
Anyone else have this experience with WLP023?