multi batches 1 fermenter

[Stone Cold]

is it possible to make a batch of wort ending up in a big fermenter then to make another batch into the fermenter up to 5 batches then pitch the yeast in the large fermenter creating a single large batch of beer?


and is it ok to make a brew then pitch the yeast a few days later. ( i couldnt find my yeast, bad prep)

 

[Mark1964]

probably not as the yeast needs pitching at a certain temp and also as soon as possible as the longer you leave it the more chance of infection. :

 

[Mephistopholes]

well this is quite often done on a proffesional scale so should be ok for you. i would just pitch the yeast as soon as the first batch is in there. andas normal maintain correct temparature.

 

[Brewmarc]

Good question :thumb: Not sure :wha: But maybe you could get the first batch fermenting & feed the other batches one by one :wha: :wha: You have to be carefull here as the yeast is sensitive to sudden changes in wort viscisity & of course tempereture (Cant remember the scientific name or reason for this ) I had a stuck fermentation once after adding sugar syrup to a wine I was tryin to make.

 

[Brewmarc]

well this is quite often done on a proffesional scale so should be ok for you. i would just pitch the yeast as soon as the first batch is in there. andas normal maintain correct temparature.

Beat me to it this is what i am trying to say :thumb:

 

[prolix]

the first batch will be a big yeast starter just keep pouring in!

 

[Brewmarc]

:wha: :wha: You have to be carefull here as the yeast is sensitive to sudden changes in wort viscisity & of course tempereture (Cant remember the scientific name or reason for this ) I had a stuck fermentation once after adding sugar syrup to a wine I was tryin to make.

Just read up on this :geek: as applicable to brewing "Osmotic pressure" the pressure exerted on the yeast cell walls in its environment ie wort. Yeast cells are very sensitive to sudden changes in osmotic pressure & will literally implode or explode :shock: causing stuck fermentationI guess a gradual change will be ok though :wha: :thumb:

 

[Aleman]

Just read up on this :geek: as applicable to brewing "Osmotic pressure" the pressure exerted on the yeast cell walls in its environment ie wort. Yeast cells are very sensitive to sudden changes in osmotic pressure & will literally implode or explode :shock: causing stuck fermentationI

You mean like throwing dried yeast into a fermenter of 1.105 wort then? . . . Seems to work OK for me :hmm: Or making a starter from a Whitelabs tube, and then throwing the yeast into a new wort?

While osmotic potential can cause harm to yeast it is generally when going from a solution with a high OP to one with a lower OP . . . The yeast have built up a reserve of 'compounds' inthe original solution so that when they go into the lower solution . . . water rushes into the cell and ruptures it . . . going the other way . . . water rushes out of the cell . . . and the yeast gradually recovers it by absorbing compounds from the external solution.

To answer the original question. . . AS long as you are brewing frequently enough it is more than possible to do this. German brewers often mash twice and the second wort(once cooled) is transferred into the FV with the already fermenting previous wort. . . . . Most commercial breweries that do this generally do two or three mashes in a day . . . rather than leaving them a day apart.

 

[Stone Cold]

interesting stuff. so it looks like the answer is yes as long as temps are identical when mixing and its all done as quick as possible. I have a target vol of 200L and my kettle is 50L. 4 x brews in a day could be tricky. and expensive if goes wrong. but a whole lota fun. Im having cloudy wort problems atm, i think i need a better false bottom who was making them to sell on thbf was it muddy disco???

 

[Brewmarc]

Thanks Aleman I was looking for a more scientific explaination :geek:
Though I wasnt really refering to the dry yeast senario you describe :nono: as osmosis clearly applies to liquid solutions, though I take your point regarding liquid yeasts :thumb: After all is it not the case that we want Osmosis to take place to some extent (obviously not to damaging effect) between yeast cells & wort allowing absorbtion of its neutrients & sugars into the cells? thus allowing for a healthy & rapid start to fermentation. Am i also to assume this is the reason why we rehydrate dry yeast?

 

[Aleman]

Osmosis specifically applies to the movement of water across a semi-permeable membrane . . . an osmotic potential exists when there is a difference in concentration of a solute (eg sugar) on either side of the membrane . . . water will move across the membrane from low concentration to high until the two solutions are of the same concentration. . . . Unless there is an active transfer taking place in the other direction.

The problem with dried yeast is compounded because in the critical few seconds following pitching the yeast cell membrane is totally non selective and allows anything across . . . including sugars which can lead to a high osmotic potential in the cell which can lead to cell rupture and a lower overall viability. For this reason it is recommended that you rehydrate dried yeast in 'warm' water before before pitching. . . the recommendation was to use distilled or deionised water . . . but this has changed recently to use water with a moderate level of mineral content.

 

[Brewmarc]

Thanks again Aleman, I am now one step closer to the "Zen" of brewing :ugeek: . Joking aside I appreciate your comments & have honestly learnt from you :thumb: the learning curve gets increasingly steeper, all good stuff. :
Marc,