Yeast dissolved in water

[merp64]

Hey,

I'm a newbie here and I like this forum a lot, it has been very helpful with my first batch of beer. I'd like to know what is the difference between adding the yeast directly to the wort, or dissolving it in hot water as it says on the package. I was confused because the instructions on the package says that I need to dissolve the yeast in hot water before adding it to the wort, but the instructions on the beer kit said to add it directly to the wort. How does it affect the fermentation?

-Thanks

 

[corax]

First, don't dissolve it in "hot" water. Dissolve it in warm water -- 90 deg. F is ideal. Much higher than 100 deg. F will kill the yeast.

Dissolving directly in wort subjects the yeast to osmotic shock: the high sugar concentration in the wort forces water out of the yeast cells. Many yeast cells die, and the ones that don't take a long time to recover.

 

[Brewer_Steve]

Yeast doesn't dissolve.
You can rehydrate it by mixing it with warm water, but it will not dissolve.

 

[Denny]

I've found it unnecessary to rehydrate the yeast before using it. Some yeast cos. say to do it, others don't. Try it both ways and decide for yourself.

 

[merp64]

Thanks for the fast replies. I had actually mixed it at 90 degrees as it stated on the package. Well it looks like that I'm good to go, thanks again!

 

[kingwood-kid]

I think one yeast manufacturer changed from recommending rehydration to direct pitching because too many people messed up rehydrating by using near-boiling water or dirty containers or whatever. The cell count in yeast packets is so high that you can safely lose a few yeast.

 

[corax]

The bottom line for me is that rehydrating is bone-simple to do, and gets active fermentation going much faster than direct pitching. It also gives you a good indication of whether the yeast is any good: no foam within a half hour of rehydration, then you've got a bad pack.

 

[KISS Brew]

I follow John Palmer's advice for rehydrating dry yeast, but ignore his suggestion on proofing yeast. The second edition of How to Brew eliminates the proofing step.

By rehydrating dry yeast, you start with a large quantity of healthy yeast to ensure a favorable fermentation.

 

[barrooze]

Definitely follow Palmer's directions. Also, try looking up the manufacturers directions for pitching the "professional" version of the dry yeast. They often have different instructions for the exact same yeast. Apparently the manufacturer thinks homebrewers beer is less important than professional beer. :-/