Pitching multiple strains of yeast into a batch

This has come up a few times and the "book" answer is it can work well. A couple of caveats: optimum temps must be compatible and the esters probably should be complimentary. Ideally you get the best of both strains and in worst case you get the best of one strain.

My experience is muddled at best. I co-pitch some great yeasts like Dupont/Blaugies and the result is inferior to a single pitch of each. I tried mixing Ommegang with Dupont and poor results again. Recently I co-pitched 3944/Conan and nothing spectacular happened . . . where each yeast had done very well independently, the mix seemed a little off.

Nothing disastrous with my co-pitching, just never hit the goals I anticipated. Will probably try it again sometime but for now I'm back to pitching one good strain.

 

As you hinted at, if you are doing wild ales this is common place.

That being said, I used multiple strains for my 25% stout - one strain to get the flavors I wanted, and another to get the alcohol.

I could see doing a few diff yeasts in a hefe to get all sorts of different esters. I wouldn't use multiple strains in a pale ale, IPA, etc, on the other hand.

 

I am a big fan of utilizing multiple yeast strains; some really work in concert of one another.

There are a few methods:

Some like to mix two+ strains and pitch at once.

Others like to pitch multiple/separate yeasts at different times.

Some like to make a starter with several strains and step it up over a somewhat long period of time and pitch at once or in doses whilst simultaneously stepping up.

My grea eat successes are in the Belgian category. Under-Pitching an early low attenuator and then pitching a mid-high attenuTive strain and varrying the temperature creates a more true to style Belgian to me, quite complex and the esters and phenols can really get funky and tasty!

I'll also at times mix several strains I a starter and do different things with it; primary strain for one beer, bottling strain for another to create strong or subtle sour profiles with funky buggy yeast.

You really need to try it out; whatever you think would work well and go for it. Take notes.

 

Yeast, White & Zainasheff, Pg. 56

"There are some tricks to adding yeast to an already ongoing fermentation. Since the fermentation is devoid of oxygen and alcohol is present, the yeast needs to be in a very active state. They should be going through an active fermentation, either from a starter, propagation, or from a one to two-day fermentation when pitched into the beer."

If yeast are active/large amount then there shouldn't be an issue. Oxygen allows reproduction, not fermentation.

 

I recently did a sour mash experiment and split it into three batches. 1 using s-04, 1 using wyeast Abbey Ale II, and 1 using a mix of the two strains. Both had been harvested from previous dark beers.

I'll say the abbey ale was the best but the mix of the two was a close second. I have started harvesting yeast from all of my brews and I think sometime soon I am going to make a beer and ferment a portion of it on a mix of all of the yeasts I have (weinstephan, abbey 2, s-04, 3711 saison, and scottish ale). Brewing is all about experimentation and having fun with it.

 

Generous beer lover beat me to the answer.

I always have the secondary yeast I'm going to co pitch ona stir plate or in a shake and bake starter fully active and ready to go when I am ready to pitch them.

I've had mostly great results. A few times the yeasts I chose just didn't compliment each other with the beer I brewed.

Experiment and see what results you get. You can always break off a single gallon and co pitch a secondary yeast so you aren't experimenting with an entire 5 gallon batch.

 

My most recent mix was WLP007 and WLP002 in a RIS. Very happy with the results. I also have mixed WLP001 and WLP530 in a Barley Wine. I will rebrew this recipe sometime this year.