Rehydrating Yeast?

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BEERBOY

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Last night i put a 1.7Kg Stockmans Draught + 1.5Kg's Extra Pale Malt Extract down. I did not use any of your idea's on hops as i just want to try this style of Full Malt beer first.
Anyway for some reason i thought it would be a good idea to rehydrate my yeast. So i put 250ml's of boiled water in a clean cup and let it cool to 35 deg. then thru my yeast in. So after 15min's it had not done much, just turned the water all milky, no foaming & bubbling. Anyway i dumped it into a very very well airated wort, and this morning the airlock is only just bubbling about twice a minute,

My question is should i pitch another yeast? & Is it ness. to rehydrate dry yeast?
& was 35 deg too hot?
 
Beerboy,
this happened to me when I tried to rehydrate the yeast to a Coopers sparkling Ale kit.
I tried to rehydrate and it was still dead after half an hour. All the yeast was sitting in the bottom of the pyrex jug.
I had spare yeast so i decided to pitch anyway. I waited about 36 hours befor I had any activity.
I was worried i would lose the brew but it worked out in the end.
I suppose its a matter of how long you want to wait. I know it was giving me the shits waiting. My limit was going to be 48 hrs before pitching more yeast. If you have airlock activity it looks like somethings happeneing. You may have a leak in your fermenter as well.
Good luck with it.
cheers
 
Beerboy,
You have to add some dextrose or DME , your yeast had nothing to feed on so it would never take off

35c is way too hot for a starter as well , you could kill the yeast at that temperture , next time add around 3 tablespoons of DME , you can use dextrose.
And starter temperture down to 25c
 
Beerboy,
35deg c was a bit warm for rehydrating the yeast.
That is a faily malty brew you did there - What was the SG?
Did you use the kit yeast? How many gramms of yeast did you pitch?
Jovial Monk posted recently on how much dry yeast you should pitch for beers over 1.050 SG and I think you will find its a lot more than what you get in the kit.

What I do when re hydrating yeast is at first I dont use the one that comes with the kit but get a SAF or similiar of known quality from a reputable brew shop.
In a sanitised beer glass I put about 250mls of boiled water cooled to 22 deg c
Pitch the required amount of dried yeast into that and let it soak up the water.
This takes about twenty minutes.
Then add a small amount of your prepared wort about 100mls ( should be about the same temp of 22 deg c) and let it start to foam. you will see a small bubbling action after a short while, now it may be pitched.
You may not need to pitch another yeast but you should get the views of someone with a bit more knowledge than me, and yes I feel it is necessary to rehydrate dry yeast.

Cheers
 
BIG BEER BELLY- The SG was about 1039 and there was a 6g of what Morgans call Larger yeast. The air lock is bubbling now so i guess it will be ok. Should i take the lid off when i get home and re-airate or will it be ok now? Also what should the FG be?
 
Batz said:
35c is way too hot for a starter as well , you could kill the yeast at that temperture , next time add around 3 tablespoons of DME , you can use dextrose.
And starter temperture down to 25c
Keep in mind rehydrating is not the same thing as preparing a starter. 35C is actually a very good temp to rehydrate at. I do it at this temp often with Safale S-04 and get good results.

Palmer recommends 35 - 40C:

http://www.howtobrew.com/section1/chapter6-5.html
 
Rehydrating is for waking up the yeasties before you put them to work. If you throw them straight in to your wort, they have a harder time of it initially because of greater pressure on the cell walls, or something like that.

A starter is for building up the cell count in a lower gravity environment, before throwing them into the wort. Gives you have a larger number of young healthy yeast ready to go to work.

Having said that, the first few brews I did I just threw the yeast straight in there and never had a problem.

Wreck.
 
Beer Boy

Big Beer Belly has it right.
Important points are;
always pitch the yeast into the 30 degree water - never the other way round.
Leave for 20 mins to allow the yeast to rehydrate.
Add dextrose or dme to the starter as they have said.
swirl to aerate the starter.
Before pitching i add some of the wort from the fermenter to the starter.
This allows the starter to aclimitise to the wort temp, sugars etc.
Let sit for 10 mins - this is usually when i move the fermenter to the laundry trough - do a OG reading - write down the recipee have a beer etc.
Then pitch into the fermenter, stir and i usually aerate with my aquarium pump and stone for three to four hours with a tea towel over the fermenter.
 
as per that other great site

rehydrate yeast at 40 deg
pitch at 26-33 deg
brewing temp 18-24 deg

works for me
 
Dry yeast should be rehydrated in 40c water--anything less will kill some of the yeast. Use 10 times the weight of plain TAP water, no sugar no dme, just tap water, as the weight of yeast.

Sprinkle the yeast on the top of the 40c water, cover and leave for 15-20 mins, then stir well. Now the yeast water will likely be hotter than your wort, so add the same amount of wort as the rehydration water, leave a few mins then add to your wort.

Sometimes the air trapped in the yeast causes the rehydration water to foam, this does not mean the yeast is active. All the yeast is doing is taking on water and coming back to "life", none of this is visible to the naked eye. Sugar in any form (i.e. sucrose or wort) might slow the take up of water and so harm the yeast.

With only 7g of yeast of which 4g might still be alive and given a well aerated wort your yeast is busily budding off new yeast cells: it won't turn, reluctantly, to using sugar for energy and so creating alcohol and CO2, untill all this oxygen in the wort is used up.




Now, the above is what that international expert in yeast, Dr Cayton Cone of Lallemand has prescribed. Ignore it at your peril!



Jovial Monk
 
Beerboy
Looks like everything is going OK and you have got some pretty good advice for the future.
I wouldnt take the lid off but just let it do its thing.
As for the yeasts in Morgans kits, i used to do a lot of Morgans before I went to grain and quite often you would get varying yeast packets under the lid particularly with Stockmans draft and Blue Mountain Lager.
I doubt very much wether the ones marked "lager" are true lager yeasts so I would just brew them out at 18 - 22 degc
I think I read somewhere once that morgans and coopers use a different strain of yeast in there "lager" packets but I am not sure.
I would brew the Stockmans with an ale yeast and the B M Lager comes out good if you use a extra pale liquid malt and use a SAF 34/70 yeast fermented at 12 -14 deg c over three to four weeks
Cheers and good luck,
 
JM, the recommendations for rehydrating "dry yeast" you have quoted are just fine for Lellamand products - as you would expect . They are not appropriate however, for DCL dry yeast who recommend around 30C max for ale and 23C max for their lager yeasts. Check out the rehydrating instructions on the DCL website - www.dclyeast.co.uk/DCL_Main/main_brewing/craftbrew_index.htm

Conversly the DCL procedure is not recommended for the Lellamand products, the subtlies of the stirring regime, use or not of sterile water or use or not of fresh wort can be a real trap. I got caught out recently with a last minute change of yeast after finding my brick of SO4 was well past its use by date and decided to pitch Nottingham. The rehydration was done in fresh cooled wort at 30C, stirred as I have always done with SO4 and pitched with what looked like a bit of activity (I think is was just foam from the whisk). The yeast failed totally and 48 hours later - after logging on to the Lellamand website and getting the correct rehydration procedure, made up a new slurry of Nottingham and re-pitched. Fermented perfectly.

The original pitching was obviously dead but the interesting point is that had I tried to rehydrate the DCL product in 40C sterile water, there would also have been a lot of dead cells. DCL claim that temps above those recommended will certainly limit viability.

Received today from Bintani (local importers of DCL) a flyer on the new Safale US56 dry ale yeast. This apparently is the same strain as Wyeast 1056 - a very popular nuetral yeast. Will hopefully have a brick to get a brew underway very soon.

Wes.
 
Yeah well mine was rehydrated at 20 C. It worked fine in the end
 
Hmmmm I have used the regime I described for Safale and 34/70 yeast, worked perfectly.

the only exception is a lager I pitched with two packets safager rehydrated as usual, got pityful attenuation, just chucked in a packet (23g) of Nottingham and it went crazy. I won't use the saflager ever again.

All ale yeasts are the same species of yeast, think the rehydration will be the same for all. Mebbe lager yeasts have different requirements but like I said the 34/70 rehydrated fine at 40C.

But rehydrate warner than 20C, Johnno!


Jovial Monk
 
JM, Using dry yeast successfully is a bit more complicated than it may appear - as both you and I have both discovered. Personally I have had great results from both DCL and Lellamand yeasts, but you have to understand the differences in the behaivour of the yeast which appears to be due to the hydrating technologies used by the respective manufacturers.

I get 3 and 4 day fermentations at true 18C for the DCL ale yeast and 5 to 7 day ferments at 10 to 12C for their lager yeats - AND I never use O2 with dry yeasts - only liquid yeasts.

And your right with your recomendation to Johnno - try 30C!

Wes.
 
What an interesting lot of comments - excellent stuff

Jovial Monk -
Saf 34/70 to my knowledge IS a lager yeast and why wouldnt you follow the DCL instructions, Maybe the saflager didnt fair to well at 40 deg c.
> Quote
I wont use the Saflager ever again< Quote
IMO there is a big difference between 40 deg and 23 deg and i would say that when all else fails read the instructions.

Wessmith-
Excellent comparison of the two procedures for the different brands of yeasts. Yor post has been very informative and i'm sure will be of benifit to all using dry yeasts.

I would like to try the new safale US56 dry ale yeast so if any of you Adelaide brew shops get it send me a PM and i will give it a go.
Cheers
 
wow, i never knew any of this!! my HBS just told me to put my yeast in half a cup of water with a teaspoon of DME for 1 hour at room temperature. It did seem to foam up like high krausen, which had me fooled into thinking it was doing something!
 
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