Encountered my first long lag time. I want to know why.

[Judochop]

My Process: I inject pure O2 with a diffusion stone, and normally run a 1 to 1.5 L starter on a stir plate using a the freshest smackpack I can find. I pitch at ‘optimal’ temperatures (usually at the lower end of the range wyeast recommends) and I see krausen formation within 12-18 hours. It’s been this way for probably 15 beers straight now, and I’ve been happy.

This time I took a Wyeast 1084 slurry from a previous batch after 3 weeks in the primary. I refrigerated it for 2 days, then on the morning of brew day, I decanted, let warm to 70 degrees, and pitched into an oxygenated porter wort @ 64 degrees. I figure I overpitched by a significant amount. Lag time was somewhere between 30-40 hours.

So, what’s the lesson to be learned here? Did massive overpitching lead to the sluggish start up? Would I have been wiser to harvest yeast after just 1, or 2 weeks? Considering that I waited 3 weeks, should I have made a little 1 pint starter just to rev the guys up before pitching?

Shower me with your knowledge and whatever please.

 

[BBL_Brewer]

When I harvest yeast from a primary, I rack to a secondary after 1 week and then split the yeast cake between two more batches. I've had good results doing this and did not experience unusual lag times. After 3 weeks in primary, a starter would definitely be a good idea before pitching to a new batch. Mr. Malty has an option for repitching from slurry that you can use to figure out how much slurry you need. Just collect that and and make a small starter with it and go from there. Or, rack to a secodary after a week and harvest fresher yeast.

 

[Misplaced_Canuck]

3 weeks since the last batch? Most of that yeast was probably dormant, I'd think. 30-40 hours is not unreasonable to see activity with a dormant yeast.

I'd probably have revived that yeast 2-3 days before pitching.

M_C

 

[Judochop]

3 weeks since the last batch? Most of that yeast was probably dormant, I'd think. 30-40 hours is not unreasonable to see activity with a dormant yeast.

I'd probably have revived that yeast 2-3 days before pitching.

Yeah, that's what I'm thinking. In the future, if I am again dealing with dormant yeast, I'm imagining that 'reviving' the yeast should only require a very small starter to get them awake and moving again, correct? Would I even need to bother with my stir plate?

Just a pint of cooled 1.025 wort and pitch at high krausen, which would be when'ish... around 12 hours later?

 

[Clementine]

+1 to the yeast being dormant, when you pitch from a starter you have got all the yeast excited and ready to go. The whole point of doing a starter, confirming viability, improving health and making sure you have the right numbers. Although you can just pitch directly with a reused cake it is always safer to do a starter.

Clem

 

[Judochop]

Pitching an insufficient amount of yeast
vs.
Pitching a sufficient amount of dormant yeast

Both increase the risk of a longer lag time, and thus increase the risk of contamination. But are they effectively the same in terms of fermentation flavor development?

I am aware that underpitching can cause off flavors due to yeast stress. In this case, however, I know my cell count was more than sufficient. (Probably too sufficient, if anything.) So, assuming that my only error was pitching dormant yeast which took a little extra time to wake up before going to work, should I still be a little afraid of off flavors?

 

[Misplaced_Canuck]

I don't think you'll have much off-flavors, in any.

I'd be pretty careful about using a large amount of slurry in a starter. I've seen explosive results!

If you have say, a pint of 3-week old slurry, I'd probably use about 4oz of solids from it, in a starter, on the stir plate for 48 hours.

M_C

 

[TheSlash]

I am experiencing this now...

Cooled my 3 gallons of 1.052 wort to 64 aerated with pure O2, sprinkled a dry packet of new Safale 04.

It's been in the ferm chamber at 65 degrees since Saturday evening. I've checked it every 6-10 hours and yesterday I had a couple of small bubbles in the blow off (prob from pressure change), but other than that, it appears no activity yet.

I'm now at about 65 hours and they say it can take up to 72 hours, but I used pure O2, temp is in range. Safale is like 62-75. And it wasn't a crazy high OG and only 3ish gallons...

Never had more than a 12 hour lag before.

Should I hydrate some notty and pitch tonight after checking gravity incase I missed it?

I can't throw the batch away as it was free wort from the Bell's homebrew challenge.

 

[scottland]

Slash, I'd pitch another pack of yeast.

I never have issues with lag time, but recently I brewed an American Amber 1.053 wort. Rehydrated a pack of Safale US-05, and pitched it at 65* like I always do. Then I set the fermentation chamber at 64* like I always do for US-05, and it didn't take off for 30 hours. I usually see signs of fermentation in around 6 hours.

This beer has been slow to ferment out also. US-05 is usually finishes my 1.055 beers in about 5-6 days at 64*. I warmed this one up to 68*, it's been 8 days, and I'm at 1.020. I guess once in a blue moon, you just get some lazy yeast?

 

[Clementine]

Check it with your hydrometer first you might just have an air leak. Bubble in an airlock and krausen and everything else are not evidence of fermentation, a change in SG is!

Before you f^&* with it make sure it ani't broken

Clem

 

[TheSlash]

I opened the bucket at lunch and I basically see the yeast just sitting ontop. No foam, no krausen, nothing... Yeast packet was plenty good. Wort was made by Bells, boiled by me. It's in temp range. I did hit it with 30 seconds of o2 at full open... but still.

I pitched safale 04, all I have now is notty.

Hydrate and pitch ASAP?

 

[TheSlash]

Thanks Clementine! I checked it and somehow I missed the fermentation. Can safale 04 really ferment overnight?? it was at 1.014 and tasted amazing already... 3 days since brew day lol... crazy crazy.