New Yeast - How old is too old?

Sure, you have to make a starter, but at what age do you become concerned about the date on the pack even though you should be able to use it?

I got a Wyeast pack from an online vendor that's almost 5 months old. The pack didn't swell and the starter took forever to get going. The time lag has me worried about using this starter. My fear is that some other bugs got in there before the intended one's had a chance to take hold.

RDWHAHB is always good advice, but in this case should I even be put in the position to worry? Would you call out the vendor on this?

The packs are supposed to be viable for 6 months. They are still good after that time period, but every month after they packet or vial is shipped out, the viable yeast count goes down and the more necessary the starter is. You could probably pitch it as is and it will start, just might take a while. Be safe, use a starter, you will be fine

I have used year old yeast....my lhbs sells it cheap..as long as you make a starter, you reproduce all the viable cells in the packet.

I have had no problem.

That is why we can bottle harvest a half gallon of yeast starter from the dregs of a bottle of Rogue beer (for example) incrementally....you just give the yeasties time to reproduce themselves....

Mr Malty

You can input the gravity you're looking for and the mfg date. It will tell you how big a starter you need to reproduce them to a good count.

Nasty said:

Mr Malty

You can input the gravity you're looking for and the mfg date. It will tell you how big a starter you need to reproduce them to a good count.

Click to expand...

I plug my information into Mr Malty along with the date on the pack and it tells me that I need 7 packs of yeast with a 2.8 liter starter.

If the pack were a month old, I'd only need one pack and a 2.5 liter starter.

Getting back to the OP, sure it can be done with one pack and stepping up the stater, but as a customer should I be expected to do this? Do you think that there is an age of the yeast where the vendor should either discount the product or at the very least, bring it to your attention that there will be extra work involved?