Should I Re-hydrate Dried Yeast?

[Benn]

New dissolvable dry yeast packaging set to hit the market late 2016; specially designed Inner pouch gradually disolves in unfermented wort. Patented packaging material allows for only H2o molecules to ingress to dried yeast cells within via osmotic action.
Should see the end of sprinkle vs rehydrate.

 

[GalBrew]

http://www.fermentis.com/wp-content/uploads/2015/12/Safale-S-04-en.pdf

Straight from the munufacturer.

What is interesting from that PDF is the recommended pitching rate of 50-80g/100L. Using an 11.5g packet for the average 23L batch is right on 50g/hL, at the very bottom of the range. Any bigger batch or if you don't rehydrate and you have yourself a nice under pitch there. No wonder so many people can't get s-04 to finish out!

 

[Bribie G]

The gospel according to Chris White in the "Yeast" book is that you should always rehydrate. On the other hand the dry yeast section is very short in the book and I wonder if it's because White is in the business of selling liquid yeast so glosses right over the dried varieties. My view is that if you are paying good money for a tiny sachet of dried granules you might as well keep as many of them alive as possible.

 

[Beers Gone Wild]

Hi,

I use the Nottingham Ale Yeast and I re-hydrate it each time, its so easy to do so why not. I have tried it both ways, from my experience I definately get a better fermentation when the yeast is hydrated as per Instructions. Nottingham requires 30-35c water temp when rehydrating.

There is a reason why they say to rehyrdate your dry yeast. This exerpt is taken from the manufacturers website - http://www.danstaryeast.com/about/frequently-asked-questions.

"Dry beer yeast needs to be reconstituted in a gentle way. During rehydration the cell membrane undergoes changes which can be lethal to yeast. In order to reconstitute the yeast as gently as possible (and minimize/avoid any damage) yeast producers developed specific rehydration procedures. Although most dry beer yeast will work if pitched directly into wort, it is recommended to follow the rehydration instructions to insure the optimum performance of the yeast."

I want optimum performance from my yeast when brewing.

 

[Ducatiboy stu]

Because yeast finds it tough to ferment the wort when it is dry

Give that yeast a beer then if it is dry

 

[Ducatiboy stu]

Because yeast finds it tough to ferment the wort when it is dry

Give that yeast a beer then if it is dry

 

[Ducatiboy stu]

New dissolvable dry yeast packaging set to hit the market late 2016; specially designed Inner pouch gradually disolves in unfermented wort. Patented packaging material allows for only H2o molecules to ingress to dried yeast cells within via osmotic action.
Should see the end of sprinkle vs rehydrate.

What if you re-hydrate the packaging first ?

 

[danestead]

You should always re-hydrate

Instructions - sprinkle dry yeast onto wort in fermenter, the yeast will take over from there

Cheers

I'm not sure if this is meant to be a joke or not, however if it is, it's probably not really welcomed as it will only confuse a new home brewer.

For those new to the game, rehydrating refers to hydrating the dry yeast in water, not wort. The reason why you do not want to rehydrate your yeast in wort is because the higher gravity, or osmotic pressure, places extra strain on that yeast coming back to life. You can either sprinkle your yeast straight onto the top of your wort in the fermenter which is referred to not rehydrating or you can rehydrate the yeast in water as per manufactures instructions which will suggest an ideal time and temperature. No need to 'rehydrate' in a sugary or wort solution as this is not beneficial for the yeast.

 

[Seaquebrew]

I'm not sure if this is meant to be a joke or not, however if it is, it's probably not really welcomed as it will only confuse a new home brewer.



Please excuse my facetious reply

I will try to refrain from such shenanigans in the future

Cheers

 

[Ducatiboy stu]

Just sprinkle onto your wort

Save mucking about getting temps correct etc


And it works......as does re-hyrdating

 

[Goose]

Why ?

No doubt been posted before but here is one possible reason:

https://bkyeast.wordpress.com/2013/03/13/more-on-yeast-rehydration/


Which does not mean you can't make a good beer by not rehydrating first, but suggests to me that the chances are better if you do.

 

[GalBrew]

 

[Goose]

Might be worth posting the results of the above experiment to save a few clicks:

 

[Ducatiboy stu]

Well that shows me that if you sprinkle at ferment temp, or re-hydrate at ferment temp then the viability is almost the same


Having the right temp to re-hyrdate is just another bit of dicking around



And there is plenty enough yeast in a pack, as has been experienced for years by simple brewers who have manged to make very good beer by simply sprinkling it on directly


And as has been asked before....has anyone ACTUALLY noticed a vast improvement in their beers from re-hyrating.....not just a " The book says so" answer




....now....where is that horse....

 

[Goose]

I see nothing wrong with this debate and it aint no dead horse, as far as i am concerned its a mustang till its broken in.

Well that shows me that if you sprinkle at ferment temp, or re-hydrate at ferment temp then the viability is almost the same

low compared to optimum agreed, but still more than double ?

Having the right temp to re-hyrdate is just another bit of dicking around

yes agreed but some of us like to dick around it improves the chances of making a better brew. in fact as homebrewers we're probably all dicks because we could also just go buy it if we didn't want to dick around.

And as has been asked before....has anyone ACTUALLY noticed a vast improvement in their beers from re-hyrating.....not just a " The book says so" answer

that's a loaded one mate,, pretty sure some do and some don't. To me its all about improving the chances of making a good or better brew. Personal choice really.

 

[Ducatiboy stu]

that's a loaded one mate,, pretty sure some do and some don't. To me its all about improving the chances of making a good or better brew. Personal choice really.

No, not really loaded....its been a question that has been raised a few times......without any actual answer......

I would be interested to see what the actual real world difference is, not just reading something and saying that it is so....

If all the extra effort does not produce a noticeable result than there really isnt much point.

 

[Benn]

Has there ever been a serious side by side brew comparison conducted?

 

[Goose]

I would be interested to see what the actual real world difference is, not just reading something and saying that it is so....

If all the extra effort does not produce a noticeable result than there really isnt much point.

if you ask me, a big part of a successful brew is pitching the necessary amount of yeast with the required cell vitality. Vitality and viability are different things but you have to start with viability. You cant have vitality without viability.

If you believe that there is no significant difference in the final product whether you pitch dry or rehydrate, then maybe you are implying that the necessary minimum vitality rate is lower than reported by the conventional yeast pitching calculators available to us on the net.

It might well be the case.

But if you believe (or believe the above experiment results) that rehydration increases cell viability then your chances of a more successful brew should still be better with rehydration. Again, personal choice.

 

[GalBrew]

Well that shows me that if you sprinkle at ferment temp, or re-hydrate at ferment temp then the viability is almost the same


Having the right temp to re-hyrdate is just another bit of dicking around



And there is plenty enough yeast in a pack, as has been experienced for years by simple brewers who have manged to make very good beer by simply sprinkling it on directly


And as has been asked before....has anyone ACTUALLY noticed a vast improvement in their beers from re-hyrating.....not just a " The book says so" answer




....now....where is that horse....

That graph tells me that if you rehydrate your yeast viability is double that if you just pitch directly. How much more of an increase do you need FFS? Are you seriously saying that double the yeast viability won't make a difference? I have noticed a difference in my beers when I started pitching the appropriate amount of yeast be it dry or liquid.

 

[Feldon]

The most interesting thing about this debate is why the big yeast companies are so obscure about which practice is best?

Perhaps they just don't know, yet. Research into yeast is still underway. Much still to be learned.

People should keep in mind that yeast used in commercial breweries experience a very different environment to what we home brewers provide them. The effect of pressure at depth in the huge fermenters they use has to factored into consideration when working out a best viable cell count for pitching yeast.

Anyway, forgive me for re-posting from this from Stu's famous thread (http://aussiehomebrewer.com/topic/74450-re-hydrate-v-not/ ) (possibly flagrant disregard of forum rules. Forgive me for I know not what I do).

I thought this was a good approach to yeast (but not life in general):

"[SIZE=medium]Sure, some yeast die if pitched dry direct into the wort. But maybe this is a good thing. They are weak yeast cells with cell walls that can't withstand the osmotic pressure of the wort. Good. Let the buggers die, and ferment your beer with decendants of the remaining strong, thick walled yeast. [/SIZE][SIZE=medium]Call it a eugenics approach."[/SIZE]