[TrippleRippleBrewer]

So, I'm trying to draw Mr. Denny Conn out here.  Have you noticed any thing different (off flavors, etc...) just pitching the dry yeast pack without rehydrating?  Anything over 1.060 I just pitch two packs, but is the rumor true that if you pitch dry yeast, without rehydrating,  it kills half the cells instantly?  This doesn't really make any sense to me, as I usually rehydrate in around 85 degree water.  Wouldn't that kill some cells too?  Why does it make a difference when you pitch into wort, is it because of the sugar content, like it's such a shock to the yeast?  Just need a little food for thought.

My experience has been that straight into the carboy is fine with lower gravity worts and one packet. If the OG warrants anything more than that, pitching two packets dried consistently gives me off flavors so I don't do it anymore.

I rehydrate. Always.
No off flavors ever, save for my recent experience with adding go-ferm to the rehydration water which I do not recommend.

Pitching dry straight into the wort forces the yeast cells to rehydrate with wort, which has hops compounds and substances that invade the cell and kill it. Many more cells die than by using straight water. My theory is pitching two packets adds more dead cells which are what contribute to the off flavors, not to mention any resulting underpitch as a result, which also adds off flavors.

Warm water is better for them. Follow the recommendations from the yeast manufacturer and I think you'll be happiest with results.

[majorvices]

Pitching dry straight into the wort forces the yeast cells to rehydrate with wort, which has hops compounds and substances that invade the cell and kill it. Many more cells die than by using straight water. My theory is pitching two packets adds more dead cells which are what contribute to the off flavors, not to mention any resulting underpitch as a result, which also adds off flavors.

Warm water is better for them. Follow the recommendations from the yeast manufacturer and I think you'll be happiest with results.

Yup. Except practically it doesn't seem to make any difference, least not on low gravity wort. Perhaps because pitching an entire pack of yeast in 5 gallons is already over pitching. Just saying, if you can't tell a noticeable difference in the finished beers all the theories and postulations ain't worth a warm Coors Light.

[alcaponejunior]

"fluffiest"

That's a great descriptor for beer.  I'm going to use that one sometime soon. 

BTW I think I'm going to go with rehydrating in H2O from now on.  I have done both, and can't tell the difference with the extremely small sample size and non-scientific comparison, but the info I'm reading seems to support rehydration in water as the best method.  Now that I've got a good setup to do this (flask w/ stir plate) I'm always ready to use my fancy new equipment too.   

[Jimmy K]

Follow the recommendations from the yeast manufacturer and I think you'll be happiest with results.

And in this case the manufacturer recommends no rehydration in one spot, and rehydration in another, so...

[TrippleRippleBrewer]

Yeah true, although what I meant was follow the rehydration procedure from the manufacturer but.....
Even dry lager yeast says sprinkle on top of the wort. I wouldn't do that but then again, I'm a rehydrator.
Nothing against those who don't. Do what you prefer and roll with it. If you're not sure, try both and decide.
Lots of folks have kicked this dead horse already here.
My leg is tired and my foot stinks so I'm done.

[anthony]

I would be curious to see if you rehydrated in even warmer water than your first experiment, more on the order of 90-100F, would you improve your viability even further.

In my experience, temperature doesn't have a statistically significant effect.

Interesting, because there is a fair amount of research out there that says otherwise... for example: http://www.sasev.org/journal-sajev/sajev-articles/volume-7-2/art3%20rehydration%20temperature%20of%20dried%20yeast.pdf

[denny]

So, I'm trying to draw Mr. Denny Conn out here.  Have you noticed any thing different (off flavors, etc...) just pitching the dry yeast pack without rehydrating?  Anything over 1.060 I just pitch two packs, but is the rumor true that if you pitch dry yeast, without rehydrating,  it kills half the cells instantly?  This doesn't really make any sense to me, as I usually rehydrate in around 85 degree water.  Wouldn't that kill some cells too?  Why does it make a difference when you pitch into wort, is it because of the sugar content, like it's such a shock to the yeast?  Just need a little food for thought.

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

[anthony]

I would be curious to see if you rehydrated in even warmer water than your first experiment, more on the order of 90-100F, would you improve your viability even further.

In my experience, temperature doesn't have a statistically significant effect.

Interesting, because there is a fair amount of research out there that says otherwise... for example: http://www.sasev.org/journal-sajev/sajev-articles/volume-7-2/art3%20rehydration%20temperature%20of%20dried%20yeast.pdf

Here is another one from DCL: http://www.fermentis.com/shared/Doc_60698.pdf which interestingly found no significant difference between rehydrating in wort or water, but still finds a difference with temperature.

In any event, I strongly suspect that the differences in pitching rate that are happening from the differences in protocols (some folks sprinkle, some rehydrate) aren't detected on the homebrew scale for a number of reasons related to the longer timeline most of us use for production, batch variation, etc.

[Jimmy K]

So, I'm trying to draw Mr. Denny Conn out here.  Have you noticed any thing different (off flavors, etc...) just pitching the dry yeast pack without rehydrating?  Anything over 1.060 I just pitch two packs, but is the rumor true that if you pitch dry yeast, without rehydrating,  it kills half the cells instantly?  This doesn't really make any sense to me, as I usually rehydrate in around 85 degree water.  Wouldn't that kill some cells too?  Why does it make a difference when you pitch into wort, is it because of the sugar content, like it's such a shock to the yeast?  Just need a little food for thought.

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

And we're done here.

[Hokerer]

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

And we're done here.

No so fast.  I think Denny'd be the first one to tell you to try it both ways for yourself and decide what works best for you.

[euge]

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

And we're done here.

No so fast.  I think Denny'd be the first one to tell you to try it both ways for yourself and decide what works best for you.

That's an assumption but yes, one should try it for themselves and not just one time and then make a sweeping decision.

[majorvices]

So, I'm trying to draw Mr. Denny Conn out here.  Have you noticed any thing different (off flavors, etc...) just pitching the dry yeast pack without rehydrating?  Anything over 1.060 I just pitch two packs, but is the rumor true that if you pitch dry yeast, without rehydrating,  it kills half the cells instantly?  This doesn't really make any sense to me, as I usually rehydrate in around 85 degree water.  Wouldn't that kill some cells too?  Why does it make a difference when you pitch into wort, is it because of the sugar content, like it's such a shock to the yeast?  Just need a little food for thought.

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

The whole point of using dry yeast for me is convenience. While boiling some water and letting it cool isn't has much work as making a starter, it's still an added step I'm not going to mess with. I do agree that rehydrating the dry yeast makes it look prettier going in the fermenter. Maybe that's what people like so much, the aesthetics.   

[tubercle]

I've done both for beer and wine. I can't tell a difference in total fermentation time or expected results. Straight dry now.

[Joe Sr.]

So, I'm trying to draw Mr. Denny Conn out here.  Have you noticed any thing different (off flavors, etc...) just pitching the dry yeast pack without rehydrating?  Anything over 1.060 I just pitch two packs, but is the rumor true that if you pitch dry yeast, without rehydrating,  it kills half the cells instantly?  This doesn't really make any sense to me, as I usually rehydrate in around 85 degree water.  Wouldn't that kill some cells too?  Why does it make a difference when you pitch into wort, is it because of the sugar content, like it's such a shock to the yeast?  Just need a little food for thought.

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

Just curious as to what dry yeasts you use with regularity.

As of this moment, I'm quite disappointed in Nottingham and US-05.  I think I can add Windsor to that list, but I'm not as certain as I haven't done side by side fermentations with it yet.

This means that my back-up-plan stash of dry yeasts is predominantly yeast I know I don't really want to use, but I suppose that's why it's a back-up plan.

[denny]

I use 1 pack, not rehydrated, for beers up to 1.070ish.  I have not had any off flavors or fermentation problems from doing that.  Until I do, I'm sticking with my procedure.

And we're done here.

No so fast.  I think Denny'd be the first one to tell you to try it both ways for yourself and decide what works best for you.

Absolutely.  That's how I arrived at my conclusion.  Maybe I should be specific and state that it's been my procedure for US05, Nottingham, S-23, S-189, and 34/70/.