Mmm.. Cake

[JestersDarts]

Good Morning Brewers –

Just racked an IPA off the yeast cake –

Started ferment 3 weeks ago, nice healthy ferment, finished to 1010 about 2 weeks ago, cold crashed 6 days ago, added gelatine 4 days ago, was going to bottle last night, but ran out of time –

So I racked it off the yeast cake into a spare fermenter – it is back in ferment fridge cold. Will skip bottles, and perhaps go to keg on the weekend (when I get my first ones).

Anyhow – I had about 500mL beer left on the bottom, so I swirled the cake all up, and tipped about half of it into a sterilised longneck – its about half full – put some alfoil on the top, and stuck it in the fridge.

Now I did this so

1. I didn't waste it
2. I could come on AHB and ask you guys what to do with it..
3. Practice making a starter..

A lot of Q's:
Did I do this wrong to make a starter?
Does it need 'washing'
Is it any good seeing there's gelatine all through it?
It was Thomas C's Kit yeast.. is it worth using again?


Cheers

JD

 

[WarmBeer]

A lot of Q's:
Did I do this wrong to make a starter?
Does it need 'washing'
Is it any good seeing there's gelatine all through it?
It was Thomas C's Kit yeast.. is it worth using again?

A couple of A's:
- No
- No
- Yes
- No

To flesh out my smartar$e answers :
- It's a perfectly valid way to collect the yeast cake, infact I do exactly this, but usually cap the longneck to keep it sterile. You've only half filled the bottle, so you have plenty of headspace there incase the yeast kicks back into action a little, so you're not risking bottle bombs (remember, gases will compress, but liquids wont)
- You could do some washing if you plan on storing the yeast for longer, some people are of the opinion the yeast remains viable longer if it is washed
- The small amount of gelatine wont contribute any noticable effects, especially as you are planning on stepping up the volume into a starter, where the gelatine will become an even smaller percentage of total volume
- Unless you're wanting a little practice in the process of washing and/or making a starter, there's no point putting in all this effort over a $2 pack of yeast. The Thomas Coopers yeast is "better" than the standard Coopers kits, but aren't as good as your bog-standard US-05, which at $5-$6 per pack is pretty darn cheap. If you were splurging $15 on a Wyeast smack pack, it makes sense to spread that cost over a couple of brews, but divide the $6 for a fresh US-05 over 30 or so long necks, and you're only paying 20 cents per longie for your yeast. Balance that cost against the risk of losing a whole batch due to an infection, and you know it makes sense to use fresh yeast.

 

[JestersDarts]

A couple of A's:
- No
- No
- Yes
- No

Cheers mate

Yeah I know its not really a yeast worth saving, but really I thought I'd save it and treat it as if it was, to get a feel for how to do it when I use a proper one.

I just wanted to know if what I had done was the 'norm' and a good way to grab the yeast to use again.

It is in the fridge cold at the moment.

I will look into making a starter, just to see if it kicks off, get a feel for stepping up amounts, gear needed etc.

which will most likely bring up a heap more questions!

I'm assuming the basics of it is,
Bring it back up to ferment temps
Feed it, get it active,
Increase the volume
Pitch during most active stagekrausen?

I'll probably transfer to a 2L coke bottle, cos I have a bottle top with bung&airlock for this, and start the above.

The things that bug me about the whole using the yeast cake is
Would I be pitching enough?
what about all the other crap that's in there?
Do I pitch the whole dang lot?

 

[RetsamHsam]

Cheers mate

Yeah I know its not really a yeast worth saving, but really I thought I'd save it and treat it as if it was, to get a feel for how to do it when I use a proper one.

I just wanted to know if what I had done was the 'norm' and a good way to grab the yeast to use again.

It is in the fridge cold at the moment.

I will look into making a starter, just to see if it kicks off, get a feel for stepping up amounts, gear needed etc.

which will most likely bring up a heap more questions!

I'm assuming the basics of it is,
Bring it back up to ferment temps
Feed it, get it active,
Increase the volume
Pitch during most active stagekrausen?

I'll probably transfer to a 2L coke bottle, cos I have a bottle top with bung&airlock for this, and start the above.

The things that bug me about the whole using the yeast cake is
Would I be pitching enough?
what about all the other crap that's in there?
Do I pitch the whole dang lot?

With the amount of yeast you have, there is no point making a starter..

You make a starter to achieve yeast growth, and by adding 2L of wort to 300-400ml of yeast you are not going to achieve this. You would only need half of this (150ml) to kick off a 23L batch of 1.048 wort.

 

[Yob]

With a few days in the fridge you can drop out the yeast... (I prefer to use a clear bottle so I can see whats going on)... Then decant off the top 3/4 of the 'beer' or sterile water and then add 400ml of sterile water.. shake the crap out of it and throw it in the fridge.. after about 10-15 min all the cake will have setteled on the bottom, you can then decant the liquid (with yeast still suspended) into another steralised jar and back into the fridge..... again after a few days the yast will drop to the bottom and you can continue to "wash" the yeast or simply bring it out few days before brew day and step it up to 1-2 lt. depending on how much yeast you have to start with.

I start with the washed 200ml yeast, (approx)

day 1 add 200ml of 1020-1040 wort (lower gravity keeps them reproducing yeast not making beer as I understand it.. Im sure someone will correct me if Im wrong)
day 2 add 400ml of 1020-1040 wort
leave 2 days
If done at brew temps and you are sure of sanitation pitch the lot ( I do not do this )
If done at room temps, then chill decant, clean and pitch..

Dont just throw your small volume of yeast into a large volume of wort.. 2 reasons being a larger volume of wort is more prone to infection before a good sized 'colony' can be established and the yeast will just get fat and lazy and not reproduce as much as they should..

there of course are more complicated and simpler ways of doing it.. this is just what works for me

:icon_cheers:

edit: the mr malty's calc si a wepon of mass creation!! Love it

 

[JestersDarts]

With a few days in the fridge you can drop out the yeast... (I prefer to use a clear bottle so I can see whats going on)... Then decant off the top 3/4 of the 'beer' or sterile water and then add 400ml of sterile water.. shake the crap out of it and throw it in the fridge.. after about 10-15 min all the cake will have setteled on the bottom, you can then decant the liquid (with yeast still suspended) into another steralised jar and back into the fridge..... again after a few days the yast will drop to the bottom and you can continue to "wash" the yeast or simply bring it out few days before brew day and step it up to 1-2 lt. depending on how much yeast you have to start with.

I start with the washed 200ml yeast, (approx)

day 1 add 200ml of 1020-1040 wort (lower gravity keeps them reproducing yeast not making beer as I understand it.. Im sure someone will correct me if Im wrong)
day 2 add 400ml of 1020-1040 wort
leave 2 days
If done at brew temps and you are sure of sanitation pitch the lot ( I do not do this )
If done at room temps, then chill decant, clean and pitch..

Dont just throw your small volume of yeast into a large volume of wort.. 2 reasons being a larger volume of wort is more prone to infection before a good sized 'colony' can be established and the yeast will just get fat and lazy and not reproduce as much as they should..

there of course are more complicated and simpler ways of doing it.. this is just what works for me

:icon_cheers:

edit: the mr malty's calc si a wepon of mass creation!! Love it

Awesome response.

So in effect, with all the 'washing' you are only keeping the top liquid, and removing the crud?

JD

 

[Yob]

indeed , anything that settles in 10 min. or so is comsumed sugas and dead yeast... rubbish.. the good yeast is milky white in colour.. if you use a clear bottle you will get to see the layering of cake and good yeast on top after a few days in the fridge!! awesome experiments.. I never knew there was a budding chemist inside me but im always friggin arround with yeast now.. love it!!

 

[JestersDarts]

indeed , anything that settles in 10 min. or so is comsumed sugas and dead yeast... rubbish.. the good yeast is milky white in colour.. if you use a clear bottle you will get to see the layering of cake and good yeast on top after a few days in the fridge!! awesome experiments.. I never knew there was a budding chemist inside me but im always friggin arround with yeast now.. love it!!

Great! yeah this is what i'm after - just want to get used to the process with this yeast, before doing it with a decent one that i'll use again a few times.

Cheers
JD

 

[Pete2501]

The cake is a lie.

 

[Yob]

The cake is a lie.

Sorry?

 

[JestersDarts]

Sorry?

yes my apologies - no real cake here

 

[bum]

The cake is a lie.

i lolled

 

[zebba]

Remember, gases will compress, liquids won't

This is a dangerous comment, and IMO you have more danger of bottle bombs from underfilled bottles then you do from overfilled.

Consider - a liquid is essentially a compressed gas. Convert that liquid back into gas and you have a much larger volume to deal with. So, CO2 in solution will actually take up less volume then CO2 in its gaseous state. Given that a certain amount of fermentables will create a certain amount of CO2, you will actually find you get MORE pressure in the bottle from half filling then you do from completely filling it.

Now, I'm NOT a scientist, so take my words with a grain of salt. But if you're worried about bottle bombs, you should definitely research further before deciding that a half filled bottle is the safe way out.

 

[WarmBeer]

It's been a long time since high school chemistry, so I'm putting my layman's hat on.

Assuming fermentation has near completed, there is a certain potential for additional CO2 to be created via secondary fermentation of any residual sugars post bottling. The slurry itself would be saturated with CO2 in solution to a certain point depending on the minimum temperature of the beer post fermentation. Any additional CO2 is going to have to go somewhere, in a half full bottle there is plenty of head space for this gas to be stored, and it will take a hella lot secondary fermentation to fill the large headspace to the point it starts to create dangerous pressure.

Again, laymans reasoning, but I stand by my assertion that you can compress gases, but not liquids.

Maybe somebody who actually does this stuff for a living should contribute, rather than you just pulling stuff out of your nether regions, troll

This is a dangerous comment, and IMO you have more danger of bottle bombs from underfilled bottles then you do from overfilled.

Consider - a liquid is essentially a compressed gas. Convert that liquid back into gas and you have a much larger volume to deal with. So, CO2 in solution will actually take up less volume then CO2 in its gaseous state. Given that a certain amount of fermentables will create a certain amount of CO2, you will actually find you get MORE pressure in the bottle from half filling then you do from completely filling it.

Now, I'm NOT a scientist, so take my words with a grain of salt. But if you're worried about bottle bombs, you should definitely research further before deciding that a half filled bottle is the safe way out.

 

[pdilley]

The cake is a lie.

Beer man! Not Portal



Cheers,
Brewer Pete

 

[zebba]

The solubility of a gas is dependent on the pressure.

http://en.wikipedia.org/wiki/Partial_press...bility_of_gases

That's why the beer in your fermenter is not carbonated whilst the beer in a bottle is - the pressure in the bottle is higher, so more CO2 is able to go into solution.

 

[manticle]

The only time I ever had exploding bottles of yeast solution (I keep longnecks of yeast and water in my fridge for re-use) was when the bottle was too full and I knocked the fridge plug out without knowing. 3787 and glass exploded inside my fridge. Stinky and messy.

Again, layman's reasoning but all my yeast bottles are half full and get brought to room temp before use. Never yet an exploding one.

Doesn't prove Jack I know - my experience only.

 

[Tony]

i want cake now

 

[bum]

i want cake now

Cake, followed by grief counselling, will be available at the end of the testing period.

 

[jyo]

I too am upset. I had pictured a Black Forest cake next to a Bock or some other description of a beer.