# fermentation lag times **URL:** \ **Category:** Ingredients\ **Created:** [September 22, 2015, 2:10pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101 "2015-09-22T14:10:11Z")\ **Posts on this page:** 10\ **Page:** 1
**Author:** ![petermmitchell](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@petermmitchell](https://forum.homebrewersassociation.org/u/petermmitchell)\ **Post date:** [September 22, 2015, 2:10pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/1 "2015-09-22T14:10:11Z")
On Sunday, I pitched 200ml of slurry into an IPA gave it 60 seconds of pure O2.  About 2 days later, I am finally seeing signs of fermentation starting.  The slurry was from an amber I brewed with wlp090 and was kept in my fridge for about 5 days prior to pitching into the IPA.  Given this lag time, I am thinking there must have been something to impact my pitch rate / viability.  Before bottling the amber I had kept it for an additional week at 75, which is what I ramped the temperature up to after the initial 4-5 days at 63, to finish out.  This was not my plan but I could not avoid it due to being on vacation.  Does this theory make sense or not?  Also, would you expect a lot of off flavors? FYI I plan to rebrew this exact recipe as soon as I can with a healthly pitch of fresh yeast.  Thanks for any help! ---
**Author:** ![system](https://us1.discourse-cdn.com/brewersassociation/original/1X/f1a2211dcb353b921ed70873794a31db2031eccc.png) [@system](https://forum.homebrewersassociation.org/u/system)\ **Post date:** [September 22, 2015, 2:56pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/2 "2015-09-22T14:56:28Z")
You should have had active fermentation within twelve hours with that much yeast.  What was the O.G. of the batch from which you cropped the yeast?  Was the slurry thin or thick?  How much non-yeast organic matter would you estimate was in your crop?  At what temperature did you pitch and start the batch?  Holding the yeast at 75F should not be the source of your problem.  That’s room temperature.  S. cerevisiae will grow at 37C, which is the temperature of the human body. ---
**Author:** ![petermmitchell](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@petermmitchell](https://forum.homebrewersassociation.org/u/petermmitchell)\ **Post date:** [September 22, 2015, 4:36pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/3 "2015-09-22T16:36:51Z")
The O.G. of the batch I cropped from was 1.054.  Slurry was normal in thickness, didn’t seem overly thick or thin to me.  Sorry if that isn’t helpful.  There wasn’t that much non-yeast matter, maybe a small layer on the bottom.  I siphon off the top of my kettle and leave the trub behind, so most of it doesn’t go into my fermentors.  I pitched at 63 and held for 3-4 days then I ramped up to 70.  I did this on batch I cropped from and current holding at 65 on the IPA, slightly higher to help speed things up. ---
**Author:** ![system](https://us1.discourse-cdn.com/brewersassociation/original/1X/f1a2211dcb353b921ed70873794a31db2031eccc.png) [@system](https://forum.homebrewersassociation.org/u/system)\ **Post date:** [September 22, 2015, 9:31pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/4 "2015-09-22T21:31:43Z")
Your experience with this strain is odd to say the least.  There has to be something that you missed?  Whatever you do from this point forward, keep good notes.  This type of problem has a way of revisiting one’s brewery.  Two hundred milliliters of slurry is a lot of cells, but it is not a ridiculous number of cells.  I am curious if there was a negative interaction between the pure O2 and the culture.  That’s a SWAG (scientific wild-\*\*\* guess) at best.  Was the period of time between pitching the amber and the IPA less that a month? ---
**Author:** ![wort-h.o.g](https://sea1.discourse-cdn.com/brewersassociation/user_avatar/forum.homebrewersassociation.org/wort-h.o.g/32/11975_2.png) [@wort-h.o.g](https://forum.homebrewersassociation.org/u/wort-h.o.g)\ **Post date:** [September 22, 2015, 9:51pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/5 "2015-09-22T21:51:43Z")
yes this is somewhat atypical with my experience and wlp090. 12-18hrs would be max with fresh yeast/slurry IME. i use O2 for couple minutes also. none of this means you’re going to produce bad beer- you will have to wait and see. ---
**Author:** ![petermmitchell](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@petermmitchell](https://forum.homebrewersassociation.org/u/petermmitchell)\ **Post date:** [September 22, 2015, 11:00pm UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/6 "2015-09-22T23:00:20Z")
Thanks for your help!  It was about 3 weeks between pitching the amber and the IPA.  Luckily now it is showing signs of fermentation finally. ---
**Author:** ![system](https://us1.discourse-cdn.com/brewersassociation/original/1X/f1a2211dcb353b921ed70873794a31db2031eccc.png) [@system](https://forum.homebrewersassociation.org/u/system)\ **Post date:** [September 23, 2015, 12:22am UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/7 "2015-09-23T00:22:49Z")
Did you manage to get any pH readings?  How heavily did you hop the IPA and the amber?  I am just curious at this point because you appear to have handled every step correctly.  That yeast strain is fairly forgiving of mistakes. ---
**Author:** ![ynotbrusum](https://sea1.discourse-cdn.com/brewersassociation/user_avatar/forum.homebrewersassociation.org/ynotbrusum/32/10316_2.png) [@ynotbrusum](https://forum.homebrewersassociation.org/u/ynotbrusum)\ **Post date:** [September 23, 2015, 1:19am UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/8 "2015-09-23T01:19:34Z")
Maybe the O2 was a bit heavy handed if you aerated after pitching?  I suggest aerating first then pitching the slurry.  Just another SWAG, but perhaps the O2 had some detrimental effect… ---
**Author:** ![petermmitchell](https://avatars.discourse-cdn.com/v4/letter/p/f05b48/32.png) [@petermmitchell](https://forum.homebrewersassociation.org/u/petermmitchell)\ **Post date:** [September 23, 2015, 1:32am UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/9 "2015-09-23T01:32:06Z")
I don’t have a ph meter so no readings, but I targeted a mash ph of 5.3 in brun water and used adjusted ro water.  The Amber was fairly hopped, used the Waldo lake Amber recipe.  The IPA is a blind pig clone, so more hopped than the amber.  I did pitch the yeast prior to the oxygenating.  Is it better to oxygenate and then add the yeast?  Which do you recommend typically to do first? ---
**Author:** ![wort-h.o.g](https://sea1.discourse-cdn.com/brewersassociation/user_avatar/forum.homebrewersassociation.org/wort-h.o.g/32/11975_2.png) [@wort-h.o.g](https://forum.homebrewersassociation.org/u/wort-h.o.g)\ **Post date:** [September 23, 2015, 11:19am UTC](https://forum.homebrewersassociation.org/t/fermentation-lag-times/21101/10 "2015-09-23T11:19:50Z")
> [@petermmitchell](#): > > I don’t have a ph meter so no readings, but I targeted a mash ph of 5.3 in brun water and used adjusted ro water.  The Amber was fairly hopped, used the Waldo lake Amber recipe.  The IPA is a blind pig clone, so more hopped than the amber.  I did pitch the yeast prior to the oxygenating.  Is it better to oxygenate and then add the yeast?  Which do you recommend typically to do first? everything i’ve read has been to aerate then pitch-not the other way. Mark should be able to comment on possible detriment pitching yeast then adding O2.