Pitching onto yeast cake

[SMOKEU]

I've currently got a 1.040 OG Coopers clone in the fermenter that I only used a single 60 minute hop bittering addition with.

I plan on making a 1.055-1.060 OG IPA and pitch onto that yeast cake. I want to save some of the yeast cake in a jar for future use.

How much of that yeast cake should I leave behind in the fermenter? I know this yeast needs a bigger pitch rate than most but I don't want to over pitch to the point of causing a loss in flavour.

 

[Pkrd]

Using a third is a good rule of thumb.

 

[SMOKEU]

Using a third is a good rule of thumb.

Sweet, it's in the fermenter now. Can't wait!

 

[SMOKEU]

I tried pitching onto 1/3 of the yeast cake. 24 hours later no activity at all so I added more of the liquid yeast from the fridge. 24 hours after that no activity either and a hydrometer reading doesn't show any change.

 

[IslandLizard]

See any foam appearing on the surface? The lag phase can take a few days.

Did you oxygenate or at least aerate? It's liquid yeast at that point, so her viability has been going down since she started to flocculate in the previous batch. Now 2-3 weeks just sitting there should not be a problem, there were plenty of cells to begin with.

Have you homogenized the yeast cake a bit before removing some to the storage jar?

 

[SMOKEU]

See any foam appearing on the surface? The lag phase can take a few days.

Did you oxygenate or at least aerate? It's liquid yeast at that point, so her viability has been going down since she started to flocculate in the previous batch. Now 2-3 weeks just sitting there should not be a problem, there were plenty of cells to begin with.

Have you homogenized the yeast cake a bit before removing some to the storage jar?

No foam at all on the surface. From my experience last time using this yeast with a 2L size starter I had a lot of krausen after 12 hours so this should be quite fast to take off.

I stirred the wort vigorously with my mash paddle up to the point it foams so much the foam almost comes out of the fermenter. I do that with every batch. About 10 minutes or so.

I did mix the yeast slurry in the jar properly before adding to the fermenter. I just raided the fridge and added the rest of my Coopers yeast to the batch along with some yeast nutrient.

I had a taste of the wort sample and it smells and tastes fine. No sign of infection.

 

[IslandLizard]

Unless you killed the yeast at some point, you did everything right. ^
Sounds like another RDWHAHB case.
Just keep an eye on it. It really should have lift off any time now.

Overpitching is not a major problem, you need to add 3-4 times the calculated amount before it starts to become noticeable, and even if so, nothing some (extra) dry hopping couldn't cure.

 

[SMOKEU]

Worst case scenario (apart from obvious infection), if it doesn't manage to take off in 48 hours I might just pitch a pack of US-05 that I have laying around in the fridge.

 

[IslandLizard]

Worst case scenario (apart from obvious infection), if it doesn't manage to take off in 48 hours I might just pitch a pack of US-05 that I have laying around in the fridge.

You didn't mention what temp you got this at now. Could that be an issue?
If nothing is happening yet, it's definitely time to pitch that US-05. It won't break your bank or your IPA.

Before you pitch, check to see if the gravity has dropped. That's important to know whether you should aerate or not.
I would rehydrate the US-05 the old fashioned way, aerate the "beer" if safe, and pitch at 68-70F. Once you start getting action, drop it a few degrees, slowly.
Or make a vitality starter with a liter of your "beer" on a stir plate (or a la shaken-not-stirred) and pitch that, to reduce lag time.

 

[Andre3000]

Something sounds odd. Anytime I've pitched onto a cake I've always seen activity within hours, including lagers that I neglected to aerate. Is there a chance you somehow removed most of the yeast? Even then, 1.05-1.06 is not that high of an OG, it should have taken off by now.

Like someone else asked, what temp? If you're at low 60s it could be slow.

 

[SMOKEU]

You didn't mention what temp you got this at now. Could that be an issue?
If nothing is happening yet, it's definitely time to pitch that US-05. It won't break your bank or your IPA.

Before you pitch, check to see if the gravity has dropped. That's important to know whether you should aerate or not.
I would rehydrate the US-05 the old fashioned way, aerate the "beer" if safe, and pitch at 68-70F. Once you start getting action, drop it a few degrees, slowly.
Or make a vitality starter with a liter of your "beer" on a stir plate (or a la shaken-not-stirred) and pitch that, to reduce lag time.

Temperature was a steady 15C (59F). Today when I added the rest of my yeast I bumped it up to 16C (60.8F). This strain (being the same as WLP009) is known for fermenting well at cooler temps than most other ales.

I'll keep checking on it.

Something sounds odd. Anytime I've pitched onto a cake I've always seen activity within hours, including lagers that I neglected to aerate. Is there a chance you somehow removed most of the yeast? Even then, 1.05-1.06 is not that high of an OG, it should have taken off by now.

Like someone else asked, what temp? If you're at low 60s it could be slow.

It could indeed be possible that I removed too much of the cake.

 

[SMOKEU]

I just had a look and there's a nice big healthy looking krausen! So I think I can save my US-05 for something else.

Next up: buying a magnetic stir plate.

 

[Beenym88]

I know this thread is a few months old but I’ve been super curious about this lately since I’ve started using more liquid yeast. You really just dump your cooled wort into a dirty fermenter? I can’t rap my mind around it with all the stress on cleaning. I do understand that it should be from a fermenter you just emptied. If anyone feels like explaining this a little more I’d appreciate it!