Rehydrating yeast

[S.R.S]

I have just started another Young's American extract kit, this time an IPA.
Although the instructions say sprinkle the dry yeast this time I rehydrated it.
When dry yeast is pitched it settles on top of the wort but after pitching the rehydrated yeast, it pretty much settled straight to the bottom.
Should I add some more yeast?
Thanks

 

[IslandLizard]

Should I add some more yeast?

No, there's plenty of active yeast to inoculate a 5 gallon batch (<1.060), unless you overheated it (>100-110F) when rehydrating.
You could swirl or stir the fermenter, but yeast "knows" what to do once she's pitched.

I doubt pre-rehydrating is detrimental to dry yeast, we've been doing that for over 30 years. Not sure if they have updated research or reformulated their products, recent instructions from dry yeast manufacturers now say to just sprinkle the granules on top of the wort, don't stir. It rehydrates from there. They're vague about why the change, but there must be good reason for it. They also claim aeration or oxygenation is unneeded. Maybe they simply want to make the process easier for novices, removing any potential barriers. Do just 1, instead of 1-2-3.

 

[Robert65]

Dry yeast is grown in an oxygen rich environment and essentially put into suspended animation, so, as is, it has all the reserves it needs without aeration. But it seems that it could expend those if rehydrated and not immediately pitched, disrupting its metabolic cycle in the absence of food.

Fermentis say their dry yeast has a coating on each granule that limits the rate of liquid passing across the barrier, so the risk of osmotic shock on direct pitching without rehydration is eliminated.

Not sure, however, if any of this is new or if in fact they are just trying to make things less complicated/ intimidating to novices, or if it applies to all manufacturers.

 

[speavler]

I always rehydrate. I believe you end up the same place, but there's a bit less lag with rehydration. Always use sterile water around 80 degrees (for ale yeast). I pitch around 70 and drop to ferm temp of 65. What was your rehydration procedure?

 

[S.R.S]

I always rehydrate. I believe you end up the same place, but there's a bit less lag with rehydration. Always use sterile water around 80 degrees (for ale yeast). I pitch around 70 and drop to ferm temp of 65. What was your rehydration procedure?

Boiled water and let it cool to approx 24c, sprinkle in yeast, leave for 15 mins then stir then leave for another 15.
I guess the water temp was too cold and I found when I stirred I got clumps on my spoon which were hard to get off
When I pitched soon after and poured in the liquid it was still clumpy so most of the yeast sank straight to the bottom.

 

[speavler]

The first stir, I get clumps. I leave the spoon in and stir again 15 minutes later and it's a nice milky liquid.

 

[brewbama]

This is how I pitch Fermentis dry yeast straight out of the package:

 

[S.R.S]

Thank you all for your input, really appreciated. Clearly the water was not warm enough when I put the yeast in and the clumps probably a result of not leaving the yeast in water long enough after stirring. That said the fermentation really took off and was much more active compared to times I have not rehydrated.
Good news.