I'm going to be an ass and paste my response from the "other" thread into this one. I really do wonder about this stuff and you fuck

nuts ignored me on that other thread......
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This is kind of an interesting thread. I personally love White Labs but I have noticed that every once in a while I get a vial that is slow to take off. I'm beginning to wonder if it can be TOO fresh.
For example, last time I brewed I made a 2L starter using 001. 24 hrs later there was no activity in the flask. I panicked and dumped the starter and went back and bought another vial of 001. It was from the same batch and same shipment. I did that on purpose to find out if it was my process or the yeast batch. I told the guys at the shop and they said no one else had mentioned a problem with any yeast from that shipment. AND they had received the shipment only the day before I bought the first vial.
Well, the second vial failed to take off after 24 hours also, but I wasn't brewing until the next day so I left it. The next morning when I checked it, it was fermenting like crazy. When I pitched the entire starter into the wort it took right off.
Factors I wonder about with starters:
I've been adding three-five drops of Foam Control to the starter at boil.
I just started adding White Labs yeast nutrient to the starter during the boil.
I use pure O2 and a SS stone to oxygenate the starter and I use a stir plate. O2 for about 45 seconds.
I wonder if White Labs does something to the yeast at packaging that really knocks it out and that if the vial sits for a couple of weeks the yeast sort of recover and are more ready to go? I dumped another batch of 001 and canceled my brew day because the starter didn't take off after 24 hrs, but that time I had to wait about three weeks to brew again. The next starter I made, with a yeast vial that had been in my fridge for three weeks, took right off.
I wonder if the Foam Control effects my ability to notice the very start of fermentation bubbles or if it somehow slows down the initial yeast growth? I don't know why it would, but?
I wonder if adding the nutrient and the O2 causes the yeast to replicate like mad but delays the production of CO2, or at least visible signs of fermentation?
I have learned to trust my process and to have faith in the White Labs yeast. If it hasn't taken off after 24 hours, just wait. Unless you have done something terribly wrong, the yeast will be fine.
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I fucking love ALL of our new high tech yeast products. My LHBS only carries White Labs so that is 99% of what I use, but I do sometimes special order Wyeast.