Stir plate give me more lag when pitched?

How does that makes sense? I pitched a 1200ml starter of WLP001 into a 1.066 OG IPA that I made last night. The starter was pitched at high krausen from a stir plate. I used to get vigorous activity in the carboy after about 12 hours before I started using a stir plate. I thought you yield the best results with a stir plate due to well oxygenated wort...? I aerate the starter for about 5 minutes with an aquarium pump, then run the stir plate with no yeast for another 5 then pitch. That takes off quickly. within hours most times. When I pitch into the wort though, it takes at least 24 hours. I aerate the wort with the same pump for 30 min using a stone as well. Does anyone have any insight as to why I have such a lag? it seems like most others see activity within hours?

What temp are you fermenting?

What was the temperature difference between the starter and the wort? You might want to add 50 - 100 ml of high gravity wort to the starter for 30 minutes prior to pitching to allow the yeast time to acclimate to the change in pressures.

andyveedub said:

I aerate the starter for about 5 minutes with an aquarium pump, then run the stir plate with no yeast for another 5 then pitch. That takes off quickly. within hours most times. When I pitch into the wort though, it takes at least 24 hours. I aerate the wort with the same pump for 30 min using a stone as well. Does anyone have any insight as to why I have such a lag? it seems like most others see activity within hours?

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Ummm..I'm a little confused on exactly what you did. So, you aerated the starter wort with an aquarium pump for 5 min then you placed it on the stir plate and ran the stir plate for 5 min then you stopped the stir plate and pitched the yeast in the starter wort. Is that correct? I'm assuming you mean the starter wort took off quickly? Did you continue to run the stir plate once you pitched the yeast in the starter wort?

sjbeerman said:

Did you continue to run the stir plate once you pitched the yeast in the starter wort?

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Of course. I understand how to use the stir plate. Yes, the starter wort took off quickly, due to the low gravity I assume.

I ferment at 68 degrees in a chest freezer with temp control.

I wait to pitch the starter till its at the same temp as the wort. which is about 70 degrees. then I put it in the chamber.