Is my fermentation stuck, and should I pitch more yeast?

[AlexKay]

I brewed 2.5 gallons of a 1.073 doppelbock and put it in the fermenter the other day. A pack of 34/70 should still be a reasonable pitch (though if it was any bigger I'd think hard about two.)

I've got a Tilt in there, so I don't have to stare at the airlock. But 24 hours in, there was just nothing going on. Gravity was absolutely, 100% flat at 1.073. This is slightly though not extremely weird: dry yeast can lag, but 34/70 is generally pretty well behaved. But my general belief is that it'll happen when it happens, that it'll start going eventually, and that even if something's not quite right, it's rare that adding more yeast actually helps.

Well, here's a pro tip: if fermentation hasn't started at all, really at all, and it's been a long time, step back and ask yourself this question: "Is it possible I forgot to pitch the yeast?"

Because yes, yes I did forget.

 

[lumpher]

Sounds like yep, it was time to pitch "more" yeast.

 

[BrewnWKopperKat]

@AlexKay : thanks for sharing that - and having a Tilt makes troubleshooting that problem easier.

---

Having started brewing a decade ago with 1 gal kits in 1 gal carboys (pro tip: for my 1 gal carboys, a Tilt might go in, but it likely won't come out), I ended up with an approach to (almost always ) ensure I pitched yeast.

A year (or two) after I started brewing, I bought one of these ...

.. for hop/kettle additions.

For labels for each box, I divided a 3"x5" note card into six squares (2 by 3) with labels like @60, @15, ....

The squares are stored in a stack with a small binder clip.

The square at the top of the stack is labeled ....

... wait for it ...

... "yeast out of fridge?"

 

[BrewZer]

The pilot in me says to print out your brew schedule and check off the steps one by one as you do them.

If you're brewing a Pils, you can call it your...


Wait for it...


Czech Liszt.

 

[OakIslandBrewery]

I brewed 2.5 gallons of a 1.073 doppelbock and put it in the fermenter the other day. A pack of 34/70 should still be a reasonable pitch (though if it was any bigger I'd think hard about two.)

I've got a Tilt in there, so I don't have to stare at the airlock. But 24 hours in, there was just nothing going on. Gravity was absolutely, 100% flat at 1.073. This is slightly though not extremely weird: dry yeast can lag, but 34/70 is generally pretty well behaved. But my general belief is that it'll happen when it happens, that it'll start going eventually, and that even if something's not quite right, it's rare that adding more yeast actually helps.

Well, here's a pro tip: if fermentation hasn't started at all, really at all, and it's been a long time, step back and ask yourself this question: "Is it possible I forgot to pitch the yeast?"

Because yes, yes I did forget.

Not many would admit that. Great you figured it out.

For yeast, I put the full packet on top of the fermenter, then when I pitch I keep the empty packet on top till I see activity.

It's a thing I started some time ago since I might forget to copy yeast details in my notes. By pitching time, it's almost the end of the brewing day so I want to wrap up the day.

 

[HM-2]

I brewed 2.5 gallons of a 1.073 doppelbock and put it in the fermenter the other day. A pack of 34/70 should still be a reasonable pitch (though if it was any bigger I'd think hard about two.)

I'd have pitched two, personally.

They recommend 80-120g/hL for warm fermentation of standard strength wort, so for 1.073 you'd be better off with two packs. If fermented cold, really you should be pitching at least three.

 

[AlexKay]

I'd have pitched two, personally.

They recommend 80-120g/hL for warm fermentation of standard strength wort, so for 1.073 you'd be better off with two packs. If fermented cold, really you should be pitching at least three.

I’ve done two for big lagers before, and I definitely thought about it.

To get into the weeds, Fermentis recommends 80-120 g/hL for 54-64 F, and I was planning on 54. A single 11.5-g pack comes out to 121 g/hL for my 2.5-gallon batch.

On the other hand, they only guarantee about 70 billion cells per pack, which comes out to 0.42 million cells/mL/deg P, compared to a standard recommended pitch for lagers of 1.5-2. But I don’t know that anyone uses the 70 billion number, not even their 80-120 g recommendation.

But it is a straight scaling with wort strength, so a 1.073 beer should only need about 50% more yeast than a standard-gravity one.

Not that I ran any of those numbers at the time! To be honest, doing small batches with dry yeast I’ve just gotten into the habit of assuming I’m never going to underpitch with a full pack. It’s not always a good assumption, and this is the exception case.

But not three packs, for a half-size batch. Especially given the price of 34/70. Whew.

 

[HM-2]

Especially given the price of 34/70

Never understood why it's so expensive for a dry yeast.