Does Wyeast 4766 (Cider yeast) have a kill factor?

[NoelMueller]

Hey guys,

The subject line says it all. I've done a lot of searching, and the best I can find is:

"many wine yeasts have a kill factor"

I can't find any definitive list of wine/cider yeasts that will kill ale yeast, and I specifically want to know if Wyeast 4766 will kill the Safale us-04 and White Labs California V yeast I pitched alongside it (don't ask).

 

[NoelMueller]

So uh..

Safe to assume nobody can answer my question? I understand kill factors are more of a wine yeast thing, but darn it, i thought SOMEBODY would know SOMETHING about this yeast.

 

[MrFancyPlants]

I am a relative newby, so take my interpretation with a grain of salt, but I think that "kill factor" is a bit of a misnomer. I think that generally when mixing yeasts, at a certain temperature, one yeast will become dominant because it is more effective at reproducing at that temperature. Sometimes depending on your source of yeast, one could take over while the other is still "lagging." That happened to me when I was doing an ESB. The wl1968 took a couple days and no sign of fermentation, so I pitched some pacman that I harvested from a bottle and ramped up on successive batches of cider. Because I had an active "starter" of pacman.. it took off as soon as it was introduced and I saw barely any of the clumps that are typical of the wy1968 in the yeast cake.

There are tons of variables though, like attenuation and the types of sugars avaiable in your wart. It is possible that some of the yeasties would be sniping the other yeasties, but I think it is about as likely as sexual reproduction resulting in a hybrid strain(unlikely without a microbiology degree) I think ale yeasts can deal with maltose better than wine or champagne yeasts.. and I am not sure where cider yeasts fall in on that spectrum.

In short there are too many variables to count, so if you really want to know how two yeast strains interact, make a 3G batch and divide it into thirds. A yeast, B yeast and AB yeast. Do a blind taste test and stick with your favorite.. Or try pacman. It makes great beer..It makes great cider.. I'm sure it would make a great graff.

 

[z-bob]

if I recall correctly, champagne yeasts will actively kill other strains, not just crowd them out.

 

[botigol]

Some yeasts, champagne are the only ones that I recall offhand, emit a protein that actively kills other yeasts.

OP, based on your other thread, it seems like you already pitched all those yeasts, so there's nothing that you could do to change the effect at this point. For educational purposes, you may want to email or call Wyeast for their response.

 

[MrFancyPlants]

I take it back.. there are killer yeasts and there are "killer susceptible" yeasts as well :

http://www.danstaryeast.com/articles/killer-yeast-strains
https://en.wikipedia.org/wiki/Killer_yeast

I stand by my advice though..

is your FG stalling out higher than expected?

 

[NoelMueller]

Yay, responses! Thanks guys.

So, I pitched the 3 types of yeast simultaneously on sunday afternoon, and held fermentation temps in the mid 60s since then. There was probably a 12-18 hr. lag period, but it looks like it fermented out in a timely fashion. I haven't taken a gravity sample yet, but I will do that later this week and report back.

My hunch is that since I pitched an un-swollen smack pack of Wyeast 4766, a less-than-viable vial of California V yeast, and a fresh packet of US-04 - the US-04 is probably going to be the dominant yeast, at least until the 4766 wakes up/propagates a bit and.. eats everything.