Fermenting Double Batch By Adding Batch 2 After A Day Or Two?

[glaab]

I asked this same question last month here http://www.aussiehomebrewer.com/forum//ind...mp;#entry659849 but got no real answer. I'm pretty keen to try it, I'll bookmark here and be back in a month or so. Good link Zwickel, thanks,I searched everywhere and found zip.

 

[Zwickel]

.... I think adding wort to an active ferment is essentially a simple version of Continuous Fermentation.

Nope, if youre going to add wort to a fermenting batch endlessly, the batch would become bigger and bigger and never came to an end. That way youd never get any fermented beer.

A continous fermentation requires immobilized yeast. Immobilized yeast has to be bound on a layer of yeast nutrient that cannot flow away with the wort.

For example: Imagine there is a large board coated with Agar and a upper layer of yeast. The yeast is bound on the Agar so much that it cannot drift away. Now wort flows over the board so slowly, that it will be fermented out, when it reaches the other end of the board. All to have to do now is, let the wort flow over the board and collect the finished beer at the end of the board.

Seems to be easy, isnt it?

:icon_chickcheers:


just found this on the web: http://assets0.pubget.com/pdf/16937245.pdf

 

[Bribie G]

Drink Dominion Breweries (DB) products. I think adding wort to an active ferment is essentially a simple version of Continuous Fermentation.

That's what I was thinking. I had a diagram of a continuous fermentation system that used to be in operation in the UK - like a big V shape but I lost it when my computer died. It was something like:



The wort would be fed in at a certain rate and would ferment in the left hand pipe, dropping the yeast to the bottom of the V - the green beer would pass over this yeast deposit and then progress up the other side of the V, dropping yeast as it attenuated and arriving at the top of the right hand pipe as green beer ready for conditioning. Obviously the yeast would build up so there would be a tap at the bottom of the V to extract excess yeast. The yeast at the bottom of the V would be analagous to Zwickel's 'immobilised yeast' as it tends to concentrate in that low point in the system.

Edit: I think there was also some sort of non return thingo near the bottom as well, so that the process could start in the Left pipe and then let the beer gradually progress into the right pipe, during the first couple of days on startup of the system.

Edit: completely off topic but I just read Zwickel's attachment. In the UK they are now beginning to use immobilised yeast 'balls' in cask real ales so they can send casks out to pubs that are clear from the word go and cask condition within a few days without the huge hassle of clearing and specialised handling.

 

[Mayor of Mildura]

Hi Bjorn

I've done this a couple of times now with no ill effects. I didn't even realise that this could potentially be an issue (ignorance is bliss I guess). In fact the ferment seemed more vigorous and the beers have turned out fine.


In my case I have brewed and pitched yeast on day one and then on day two brew and add to fermentor.




I say go for it man.

Cheers

MOM

 

[BjornJ]

Thanks for a lot of good info, guys.

Guess it's either cube day 1 and pitch it all on day two or just try it out by adding the second batch when it is brewed.

So far I haven't even got the big fermenter, just thinking out loud here if it would be worth it (as in would
I be able to ferment anything that big, how the Hl am I am lifting a 60 litre fermenter out of the fridge and on to something to rack/bottle from? What do I rack my then only 60 litre fermenter into, maybe 2/3 cubes?, will 2 cubes fit in my fermenter, etc, etc)

TB gave me a lager/pilsner recipe to try out to get my baseline lager, been thinking for a while about doing a double batch as the brewing of lagers take so long when I choose to add a "bulk lagering" step.

My first lager was a bit bland, my second one tasted funny, the last one was infected with Lacto bacillus I had from good sources, so let;s try a new recipe and double batch just to up the stakes



thanks
Bjorn

 

[Nick JD]

Not necessarily worse, not better.... Just not the same.

Worse - have you not tried DB Draught?

EDIT: off topic, but here's a pdf on Kiwi continuous fermentation written by a DB employee for anyone interested. Interesting read. I like the bit about not having to clean the vessels for a year...

http://nzic.org.nz/ChemProcesses/food/6A.pdf

 

[ekul]

I will be trying this tmo. I cubed (first time) a double batch of cpa clone into 3 15L cubes. Sadly one of the cubes lids didn't fit on. I tested them all at bunnings and they were fine, then i tested them all with water at home and they were fine. But for some reason the hot wort must've warped the lid or something as then one wouldn't seal properly. Will be taking it back on monday, i hate it when bunnings sells faulty gear (the amount of leaky taps i;ve had from there is ridiculous!)

I chucked it in the bar fridge (which i would've like to have cleaned but didn't have time) to cool rapidly but it was still too hot by 1am this morning so i had to wait till this morning. Pitched white labs 'australian ale' at 6am, such an awesome yeast. I love how with cubes the oxygenation caused by tipping them in really sorts the wort out, this thing is already bubbling.

I have another fermenting fridge but it is currently full with a 60L fermenter, won't be getting anything more in there! I should be bottling it today or tmo.

So just to check... ONce the 60L fermeter is ready I will siphon the cubes into the 60L fermenter gently and then gently add the 15L of fermenting wort? I will taste the fermenting wort to see if it got infected. Why when people add big starters do they not get issues with oxidisation?

I would just ferment them separately but i only have temp control for one fridge, the bar fridge is for cold crashing 30L fermenters atm.

 

[Bribie G]

Ekul
Just to make sure we are on the right track, what will the exact lag be between pitching the first fermenter then adding the other two?
If it's only two or three days and fermenter #1 has been fermenting fairly cool, then I would actually aerate the wort to buggery and then pitch the 15L so that the yeast will stay in the 'breeding up' stage.
With some yeasts such as Ringwood and 1469 I deliberately thrash the wort for the first couple of days, morning and night.

Similarly with big starters such as lager, they have a big oxygen requirement initially, before they then settle down for the anaerobic alcohol producing phase, so no problems with 'oxidisation' - more like 'oxygenation' which is a good thing in the first few days.

 

[ekul]

Ekul
Just to make sure we are on the right track, what will the exact lag be between pitching the first fermenter then adding the other two?
If it's only two or three days and fermenter #1 has been fermenting fairly cool, then I would actually aerate the wort to buggery and then pitch the 15L so that the yeast will stay in the 'breeding up' stage.
With some yeasts such as Ringwood and 1469 I deliberately thrash the wort for the first couple of days, morning and night.

Similarly with big starters such as lager, they have a big oxygen requirement initially, before they then settle down for the anaerobic alcohol producing phase, so no problems with 'oxidisation' - more like 'oxygenation' which is a good thing in the first few days.

Well i brewed the 3 15L cubes full of wort on the friday. I pitched the yeast for one of them on saturday morning. Its white labs australian ale yeast.
I was hoping to bottle the 60L fermenter today but its on 1.013 and i have a feeling that it may drop to 1010 or maybe lower. Anyway that whole batch got a whole heap of iodophor in it (amongst other things ) and i am a little apphrensive about drinking it, so i don't really mind bottling it earlier because i'd rather have one good batch then two mediocre ones. Plus i think that batch may be infected, no reason to believe it, just that too many things went wrong for it not to be infected. The hydrometer samples taste a little funky, not infected but not nice either. Kibnd of tastes like it has been fermenting hot or something, but it hasn't. Doesn't have banana-ery flavours like you'd expect from a cpa brewed hot either, just the other 'hot' flavours. It was boiled for a good 3hours probably, kept getting dirty things (and vinegar flies) falling in the cooling wort so i had to keep boiling it. When the iodophor went in i thought bugger it and just transferred it into a fermenter to cool. Its not going to be a good batch.

So anyway i should be bottling that batch tmo which will free up the 60L fermenter.

So assuming i pour the cubes (30L) and the fermenting cube (15L) into the fermenter at 4pm tmo the first 15L cube would have been fermenting for 58hrs (nearly two and a half days). So should i aerate then or just siphon gently? Can't wait fot his batch to be ready, i;ve had so many dud batches in the last month and the stocks are getting low.

thanks for the help mate, i appreciate it.


Do you know how much iodophor is bad for a person? Cause it was so hot the iodophor changed to clear really quickly so i'm hopng most of the sanitiser had been evapourated.

 

[ekul]

I was advised to add the fermenting wort and the cubes very gently, however this morning i found that adding cubes gently is actually quite difficult. SO the whole lot got aerated.

The fermenting wort was at 1030 so it hasn't femented too much, i'm hoping it will be alright, if not it will be a good experiment.

The only bad thing is that the fermenting wort tasted not quite right. However i've never tasted mid-fermented wort as i usually throw my hydroometer in the brew and check it via the gladwrap lid. So maybe htats how partially fermented wort tastes like?

I will let you all know how it turned out when its finished.

 

[Hatchy]

snip...

So far I haven't even got the big fermenter, just thinking out loud here if it would be worth it (as in would
I be able to ferment anything that big, how the Hl am I am lifting a 60 litre fermenter out of the fridge and on to something to rack/bottle from? What do I rack my then only 60 litre fermenter into, maybe 2/3 cubes?, will 2 cubes fit in my fermenter, etc, etc)
....snip

I can fit a 60L fermenter in my ferment fridge but not 2 30L fermenters. I've thought about somehow elevating the fridge but I've decided that is almost certainly a bad idea. If I'm bottling (which I avoid wherever possible) I use a cube as a bottling bucket to get 20L out so that the fermenter is movable. Kegging is much easier (amazingly), you can fill the 1st keg without having to move the fermenter which again means that you can move the fermenter to fill the 2nd keg or to bottle the rest.

As far as the original question, my 1st instinct would be to cube the 1st batch & wait for the 2nd batch to be ready.