Using two yeasts

[jeg3]

For my latest brew I attempted to rouse a packet of WY1968 that had been at the back of my fridge for a few months - with a starter, but there was no sign of activity a couple of hours before pitching time, so I also added a batch of Wye Valley yeast I had in the fridge to the starter.

This rapidly woke up and I pitched the whole lot.

The two strains are quite different in terms of their AA.

So to my surprise tonight I take a sample of the brew after 4 days and it's dropped from 1.042 to 1.012. All my beers using the Wye Valley have dropped to 1.008 after 4 days.

So does this mean the 1968 has woken up?

And that got me thinking, when using a dual strain, can one strain be more dominant?

Would be interested to hear the thoughts of any yeastophiles...

As for the beer, well it tastes as expected...!

 

[Simonh82]

I read an interesting article in the Journal of the Institute of Brewing which was a review of someone's career working with yeast in brewing. He said that one of their discoveries had been that using two strains can lead to premature flocculation in some instances. Saying that a lot of breweries did use dual strains without problems.

It could be that the 1968 strain took over and led to lower attenuation, or it may have just finished a little short this time. Did you mash slightly hotter this time?

 

[jeg3]

If anything it was slightly lower (only by 1℃, but apparently that can make all the difference), so I would have expected a lower FG.

It makes no real difference as my process control is poor at best, and the first taste test was awesome.

But my yeast experimentation continues...!

 

[CreweBrewer]

Adnams yeast is a blend of two strains.

Dave

 

[geetee]

I just made a brew using lager malt and Wolf, Motueka and Rakau hops. I am brewing it as a light summer ale rather than a lager so used S04 yeast. I never checked the yeast and it may have been out of date (been in the fridge a while) however it took off like a rocket and fermented out in 3 days down to 1008.

I checked the brew and there was a distinct buttery smell and taste so suspected Diacetyl, something I normally don't get. I was suspicious that the yeast may have been old and stressed causing the diacetyl and may not be able to clean it up so I have pitched a packet of Nottingham to help it out.

After two days at 16°C the smell is dying away and I will then cold condition. It may be that it might have cleared anyway but I think adding the Notty has helped. Not sure what effect if any it will have on the flavour but since fermentation was complete I reckon it should not be significant.

First time ever for using two yeasts in one brew.