Mix and matching yeasts

[The Green Man]

Hello brewers. I am currently buying 15g packets of yeast. They are pretty cheap and are re-packaged Fermentis yeast from Oz. With my small batches (9 litres max) 15g is overkill. I'm using 10g, which might also be too much...
So can I mix 5g S04 with 5g S05 in a British Golden ale. What do you reckon? A thoroughbred in the making, or just an ass?

 

[J A]

No problem mixing dry yeasts. Results are unpredictable, though. Sometimes one will overpower the other but if they both have similar lag times, they'll both get going and give good results and you'll get character of both yeasts. With the S-04/US-05 mix, I'd expect the US-05 to give some good ester contribution with the 04 keeping things a little cleaner than 05 alone and helping with stronger floculation. Depending on grist, slightly bready with some light fruit from the yeast. Ferment at 66 degrees...lower may give you peachy flavor from the 05 and higher may give you harsh fruit notes from the 04.

 

[The Green Man]

Cheers JA. 66f, or 18c to us squirrels, is my usual fermentation temperature. Might give it a go, sounds interesting.

 

[J A]

Another thing that's a little hard to predict is attenuation. Just to be safe, assume somewhere in the middle of the two averages. Also I've used a pitch rate of 5.5 grams dry yeast (rehydrated) per 9 liter batch with consistently good results.
For a 5-6 gallon batch of a mixed yeast cream ale I pitched a full 11gram pack of each yeast and it was great. Overpitching won't hurt. Your plan should work very nicely.

 

[The Green Man]

Another thing that's a little hard to predict is attenuation. Just to be safe, assume somewhere in the middle of the two averages. Also I've used a pitch rate of 5.5 grams dry yeast (rehydrated) per 9 liter batch with consistently good results.
For a 5-6 gallon batch of a mixed yeast cream ale I pitched a full 11gram pack of each yeast and it was great. Overpitching won't hurt. Your plan should work very nicely.

Thanks JA. Really appreciate the input. I wilI go for it with my next brew, Summer Gold. I have a feeling, I have been over-pitching. On the yeast calculator I use the Pro-brewer 0.75 setting and I always re-hydrate. The calculator comes up with 5g as being short. But, like you say over-pitching is definitely better than under pitching. Do you recommend changing the Yeast Calculator setting?

 

[J A]

But, like you say over-pitching is definitely better than under pitching. Do you recommend changing the Yeast Calculator setting?

For clean-tasting ales I don't think you have to worry about over-pitching, but if you're looking for certain flavors out of Belgians or Hefeweizens, you may lose some character from phenols/esters if the lag/reproduction phase is skipped.

I never worry about the yeast calculator unless I'm doing a starter and then, I just get it sort of close. Any time I can, I brew a low-gravity beer with one 11-gram packet of yeast and pitch a higher gravity beer on the cake. And maybe one more after that. That's a massive over pitch, but it always gives good results.