Dry Yeast starter

[DaksBrew]

My yeast starter that I just bought from Northern Brewer has instructions for using a wyeast smack pack. My question is whether I use the same procedure for dry yeast?

I've seen people on the Internet saying I need to rehydrate the dry yeast by boiling water n letting it cool to 90-100 degrees and then pitching the yeast into it.

In my instructions it says to pitch the yeast into a small wort sample that has been cooled to room temp.

What is the correct method?

 

[maffewl]

You don't need a yeast starter for dry yeast. Nor do you "have" to re-hydrate it. You could just let the wort cool to pitching temp and pitch... however, re-hydrating is preferred.

 

[DaksBrew]

So dehydrating is just putting it in a lil bit of warm water right? 90-100 degrees farenheit?

 

[maffewl]

Not de-hydrating... that would be the removal of water. Here is a how-to on re-hydrating dry yeast provided by Danstar for Nottingham.

http://www.danstaryeast.com/library/rehydration-and-usage-tips-ale-yeast

However, anytime I use Notty, I usually don't re-hydrate at all. I just remove the yeast from the fridge and allow it to come to room temp while I'm brewing and pitch it when the wort is at the right temp. Re-hydrating is nice, but not absolutely needed.

 

[shanecb]

If you rehydrate it, using just warm water is much better for the yeast than a sample of wort. Helps to build up healthy cells!

 

[DaksBrew]

Ok thanks bro!

I actually meant RE-hydrating but I'm on my iPhone and autocorrect spellings a pain.

 

[Carter1932]

Interesting that Danstar says 'aeration of wort not necessary'. Is this something unique to dry yeast? So what's different with Notty that makes aeration not necessary?

 

[DaksBrew]

Is it okay to use a yeast starter with dry yeast? Or even possible?

 

[ArcaneXor]

Interesting that Danstar says 'aeration of wort not necessary'. Is this something unique to dry yeast? So what's different with Notty that makes aeration not necessary?

I believe Danstar's statement derives from the fact that, when rehydrated properly, you end up with more than 200 billion viable cells in the wort, which is enough to ferment most batches without additional propagation. But I still aerate dry yeast pitches because I am never quite sure what abuse the yeast satchels took and how successful the rehydration was. It's just insurance in case of an unintentional underpitch.

Is it okay to use a yeast starter with dry yeast? Or even possible?

It's certainly possible, but not usually desirable. White/Zainasheff flat out say "no" in their yeast book, arguing depletion of cell reserves. For me, it's mostly a matter of economics - making the starter costs nearly as much as an extra satchel of yeast. If you wash/re-use dried yeast, you would, of course, treat it just like any liquid yeast slurry after the initial pitch. But again, there is the question of whether washing dry yeast makes economic sense.

I usually don't re-hydrate at all. I just remove the yeast from the fridge and allow it to come to room temp while I'm brewing and pitch it when the wort is at the right temp. Re-hydrating is nice, but not absolutely needed.

Reportedly, cell viability is reduced by up to 50% by failing to rehydrate, since the yeast cells cannot control what passes in or out of their cell membranes until they are fully hydrated. The surviving cells may suffer in vitality, resulting in a sub-optimal pitch with as few as 100 billion cells. That can result in undesirable flavor profiles.

 

[zachary80]

+1 to what ArcaneXor said. A nice restated version of the relevant portions of "Yeast"