Explaination of "Pitching Yeast"

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

RotorHead6

Well-Known Member
Joined
Jan 16, 2007
Messages
86
Reaction score
0
Can someone please explain when you should pitch yeast and when you should not. I confused as to what yeast needs to be pitched right before placing into the primary and what yeast needs to be pitched longer. Thank in advance.
 
Are you talking about making a starter? Assuming that you are, dry yeast does not require a starter, it only needs to be rehydrated before adding to the wort. Liquid yeast should always have a starter (even the so-called "pitchable" tubes and smack packs). I typically make my starters 36-48 hours in advance of brewing, more if I am making a big beer and plan to step up the starter to increase cell count.
 
Sorry guys, I did mean a starter. Can you explain the steps in making a starter?
 
Well, here is a quesiton: Is there a wrong way to rehydrate the yeast?

I know that sounds dumb, but the package said to pour yeast into cool, boiled water. Do NOT stir, then after 10 minutes, stir vigorously and pitch into wort.

Well, after the water cooled from a boil, I threw in the yeast packet and there was a "pile" of dried yeast that never got to the water because it was never stirred, itjust sat there and was then stirred before pitching.

the reason I ask is i had a no longer fermenting/bubbling issue on monday and didn't think till today, maybe the yeast wasnt hydrated and thats why it only fermented for 30 or so hours
 
it should be fine, you can pretty much just throw it in there, although rehydrating is always a good idea.

and just because it's not bubbling doesn't mean it's done fermenting. give it a week, then check your specific gravity
 
With dry yeast really all you "need" to do is dump it into the fermenter. Don't have to rehydrate.
 
Rehydrating dry yeast prepares them to ferment the wort and ensures that as many cells as possible survive the initial pitching. I guess this is like ensuring viability.

From the Danstar FAQ page (http://consumer.lallemand.com/danstar-lalvin/beerfaq.html):

"For the initial few minutes (perhaps seconds) of rehydration, the yeast cell wall cannot differentiate what passes through the wall. Toxic materials like sprays, hops, SO2 and sugars in high levels, that the yeast normally can selectively keep from passing through its cell wall rush right in and seriously damage the cells. The moment that the cell wall is properly reconstituted, the yeast can then regulate what goes in and out of the cell. That is why we hesitate to recommend rehydration in wort or must. Very dilute wort seems to be OK."

The FAQ goes on to say:

"We recommend that the rehydrated yeast be added to the wort within 30 minutes. We have built into each cell a large amount of glycogen and trehalose that give the yeast a burst of energy to kick off the growth cycle when it is in the wort. It is quickly used up if the yeast is rehydrated for more than 30 minutes. There is no damage done here if it is not immediately add to the wort. You just do not get the added benefit of that sudden burst of energy.

How do many beer and wine makers have successful fermentations when they
ignore all the above? I believe that it is just a numbers game. Each gram of Active Dry Yeast contains about 20 billion live yeast cells. If you slightly damage the cells, they have a remarkable ability to recover in the rich wort. If you kill 60% of the cell you still have 8 billion cells per gram that can go on to do the job at a slower rate."

This information is from Danstar, but I bet it also applies to Safale yeast. Even though the Safale package says it is ok to just sprinkle the yeast on the wort, they do give rehydration instructions on the Fermentis website (http://www.fermentis.com/FO/EN/06-Ales/40-10_directions_hb.asp).
 
What I do is sprinkle dry yeast on a cup of boiled water after it has cooled to around 95 degrees. After 15 minutes I stir it up, and 15 minutes later I pitch it into the wort.
 
Fermentis/Safbrew yeast should indeed be hydrated. the way they dry their yeast, it really comes alive in water and forms a creamy milk with a krausen in about 30 mins.
pitch that and yer bubbling in an hour or two...in my experience.
 
:tank: I rarely rehydrate yeast just because it is one more thing a noobie can screw up. I think when you have couple of batches under your belt and you have all your sh#t together and you are organized, it is a small step to rehydrate. Most of your dry yeast is so much more cells I don't think it makes a whole hell of a lot of difference. I started making bigger (7.5 gal. batches) that I've started using yeast nutrient from the LHBS.:mug:
 
Back
Top