Old yeasts?

[46binder]

I have had some really slow fermenting beers, some have been taking 24 hours to see activity. I just did a Centennial Ale on Friday, 48 hours ago, no activity. I have been thinking its just the temp, my basement is about 60 degrees, and the carboys and buckets sit directly on the concrete floor. The Centennial was dry yeast, hydrated. I just got a new erlenmyer flask, and did a starter for an ESB from a smack pack. I was going to brew it today, but it is incredibly slow, and I saw the date was Nov of 2013. Has my LBS been selling old yeast? The dry yeasts are not refrigerated either. Big deal? I want to get more into the yeast end of brewing, and want faster fermentations. Pitch more yeast? Try mail order yeast? I have tried Farmhouse before with good results. Is the Centennial screwed?

 

[khawk95]

60 is cold for most ale yeast. What kind of dry yeast did you use? That would give us an indicator of the issue. The ESB yeast should be well above 60 or it won't get going very well. Depending on the strain, I would target 68-70 for the ESB.
It will likely get going, just slowly. I would get it off the concrete and try to warm the fermenters up. If you warm up to 66 and nothing happens, I would repitch.


Roed Haus Brewery

 

[WoodlandBrew]

I too would expect the temperature to be the culprit here before suspecting vitality, but without knowing the strain it's just a guess. I haven't tested viability of dry yeast stored at ambient, but off the cuff, I would guess that 6 months would have some impact to viability. Although yeast is pretty hardy. Yeast used for making bread is the same species as that used to make beer. I've had yeast in the cupboard for years that still makes adequate bread.

Here is some information on yeast viability under different conditions:

http://www.woodlandbrew.com/2013/01/abv-effects-on-yeast.html
http://www.woodlandbrew.com/2012/12/refrigeration-effects-on-yeast-viability.html