US-05 Looks/acting different

[refect]

Hello all! I couldn't really find much info on this...Yesterday I brewed up one of my go to IPA recipes. I chilled the wort to 75 degrees and pitched a packet of us-05. I then aerated and put the carboy in my fermentation fridge for a slow chill to 64 degrees. About 12 hours later I had a good layer of krausen on top, but the yeast looks very clumpy with no activity in the wort. It is just a bunch of yeast clumps floating with no real movement or activity. The airlock is also bubbling pretty slow, so I know something is happening, but it is not what I am used to seeing with this yeast. I have never seen this strain of yeast clump up like this, and I usually see my wort swirling around like crazy as the yeast do there thing. I use this yeast along with WLP001 a lot and have never seen them act this way.

- OG was 1.067
- I used one packet of us-05 sprinkled into the carboy (typically I have always used this yeast without rehydrating and no problems)
- pitched at 75 then slow chilled over the course of 5-10 hours to 64 where it will stay to ferment.
- Yeast packet was brand new, but was stored at room temperature.

Has anyone else seen us-05 clump up and hardly move like this? Should I warm the temps up a bit? It has only been 12 hours, so I know it is still early. I am just used to seeing a vigorous fermentation fairly quick with this strain and not the clumping with no movement in the wort. They look like WLP002 in a way right now. My main concern is that I will get a stuck fermentation. I have another us-05 packet. Should I dump that in if things don't progress after 24 hours? I attached a picture, so you can see what I'm talking about...

 

[McKnuckle]

It looks more like floating break material to me than yeast, especially only 12 hours after pitching. I usually don't see lots of visible activity from US-05 until 18 hours have passed. Perhaps when you aerated after pitching as opposed to before, you caused yeast to bond with other bits in the wort, causing some clumps. But they'll figure out that there's food to eat - not to worry!

I wouldn't bother warming it up, although 68-70F is still fine for that strain. It's rather difficult to keep viable yeast at bay, so don't get paranoid and scuttle your plans so early in the game.

 

[VikeMan]

I agree; it looks like break material.

 

[refect]

I agree; it looks like break material.

You know for whatever reason this did not come to my mind. I've used this yeast many times and am used to seeing them going to town on my beers. I've always thought this was yeast clumps that you sometimes see in British strains. Break material makes more sense to me. Especially with this strain. I'll just wait it out and see what happens. They are just moving a bit slower than I am used to. They will probably explode when I least expect it.

 

[smata67]

That does look odd. S05, though reported to be the chico yeast like wlp001, seems to behave differently. Which makes sense, as it is packaged in a completely different format. I have found it to be slower starting and just more sluggish in behavior overall. Krausen is subdued, like under 1 inch, whereas wlp001 is frequently 2-3 inches. But taste and attenuation are the same. I bet if you hydro monday or tuesday you will see 1.012 or so FG, which is fine. Wait another week to bottle.

 

[VikeMan]

S05, though reported to be the chico yeast like wlp001, seems to behave differently. Which makes sense, as it is packaged in a completely different format.

US-05 and WLP001 have been genetically tested and are different strains.