Mashing over two days - adding fresh wort to ongoing fermentation

Enskede Brewery

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Hi brewers.

I am planning a 50L batch of beer in a couple weeks time but my Braumeister/Brewmaster system is only for 25L, so I need to mash two times. However, my only time to brew is during weekends and with summer coming (the only time of year when Stockholm is wonderful to live in), I have chores and pleasures during the weekends to beyond brewing :). My plan is to sneak up early in the morning before the family wakes up and mash a 25L batch on Saturday and a second batch on Sunday. This will give me time for other things from lunch onwards.

My plan is to start the ferment of the first (Saturday) batch as soon as it has been cooled from the mashing and boiling, giving it as little time as possible to catch anything. And then, when I have mashed, boiled and cooled the second (Sunday) batch, I plan to add the fresh wort directly into the fermenter of the Saturday batch, more or less exactly 24 hours after the first batch, which by then should have passed it's lag phase and be starting to consume the sugars of the Saturday batch.

Here's my question: do you see anything problematic with this approach? Would you want to talk me out of it? Why? Or are there things about this approach I need to consider and adjust for?

I can think of a few things. How much yeast to pitch - should I pitch yeast based on 25L or 50L? The same with yeast nutrients, should I add for 25L or 50L. Could I shock the yeast by adding so much fresh wort? PH?

Why aren't you just fermenting the two batches separately, you are right to ask. I could, but I'm running out of buckets. I am also cheap on the yeast, so I was hoping this would be a way to use less yeast.

I've never done this experiment before, so I am hoping you guys with more experience have done this before, or see the obvious flaw in my plan. Thanks in advance!

/Pal
 
Hi brewers.

I am planning a 50L batch of beer in a couple weeks time but my Braumeister/Brewmaster system is only for 25L, so I need to mash two times. However, my only time to brew is during weekends and with summer coming (the only time of year when Stockholm is wonderful to live in), I have chores and pleasures during the weekends to beyond brewing :). My plan is to sneak up early in the morning before the family wakes up and mash a 25L batch on Saturday and a second batch on Sunday. This will give me time for other things from lunch onwards
My plan is to start the ferment of the first (Saturday) batch as soon as it has been cooled from the mashing and boiling, giving it as little time as possible to catch anything. And then, when I have mashed, boiled and cooled the second (Sunday) batch, I plan to add the fresh wort directly into the fermenter of the Saturday batch, more or less exactly 24 hours after the first batch, which by then should have passed it's lag phase and be starting to consume the sugars of the Saturday batch.

Here's my question: do you see anything problematic with this approach? Would you want to talk me out of it? Why? Or are there things about this approach I need to consider and adjust for?
This is not a problem at all. Very common practice in commercial brewing. I just carbonated a double batch that was brewed on 2 back to back days.

the only thing to consider is that you dont want to push o2 on the second batch. otherwise treat it the same.

common practice when you buy small pitches to propagate the yeast up for a full sized batch.

We leave the product line hoooked up and clean it in place(caustic cycle and then burn it with 180f hot water). just be sure all of your gear is clean and santizied before you push in the second batch.
I can think of a few things. How much yeast to pitch - should I pitch yeast based on 25L or 50L? The same with yeast nutrients, should I add for 25L or 50L. Could I shock the yeast by adding so much fresh wort? PH?

Why aren't you just fermenting the two batches separately, you are right to ask. I could, but I'm running out of buckets. I am also cheap on the yeast, so I was hoping this would be a way to use less yeast.

I've never done this experiment before, so I am hoping you guys with more experience have done this before, or see the obvious flaw in my plan. Thanks in advance!

/Pal
Send it!
 
A point of question:

You have batch one completed, are you chilling, pitching yeast?
if so, do you pitch all the yeast for both batches, or half for batch one and half for batch two?

If not pitching the yeast, I presume you’re still t/f to the fermenter and just holding steady temp until yeast pitch?
 
A point of question:

You have batch one completed, are you chilling, pitching yeast?
if so, do you pitch all the yeast for both batches, or half for batch one and half for batch two?

If not pitching the yeast, I presume you’re still t/f to the fermenter and just holding steady temp until yeast pitch?
Yup pitch yeast on the first batch and it will propagate up in the 24hrs until the second batch is ready.

We have done a 15 bbl pitch into a 30bbl batch and watched cell counts to brew a second 30bbls into it to get a full 60. Generally less then 48 hrs between batches. Not optimal but gotta do what you gotta do. Big pitches are pricey.
 
This is not a problem at all. Very common practice in commercial brewing. I just carbonated a double batch that was brewed on 2 back to back days.

the only thing to consider is that you dont want to push o2 on the second batch. otherwise treat it the same.

common practice when you buy small pitches to propagate the yeast up for a full sized batch.

We leave the product line hoooked up and clean it in place(caustic cycle and then burn it with 180f hot water). just be sure all of your gear is clean and santizied before you push in the second batch.

Send it!
Perfect, all made sense what you said. I have OCD when it comes to cleaning and sanitizing my brewing equipment, so will definitely be clean stuff for day 2. I am relieved - thanks!

So would you be pitching yeast according to the volume of both batches or just for the first? I would assume I need to add nutrients for both batches.
 
Perfect, all made sense what you said. I have OCD when it comes to cleaning and sanitizing my brewing equipment, so will definitely be clean stuff for day 2. I am relieved - thanks!

So would you be pitching yeast according to the volume of both batches or just for the first? I would assume I need to add nutrients for both batches.
thats your call. I would just pitch for the full volume and let it ride, but you are basically propping up a yeast pitch so you could get away with the smaller pitch(as long as it is good for the single batch). We had a lab so it was very different. our general schedule was 2-3 shifts a day brewing 60. sometimes we would squeeze in a 90 if we were tight schedule wise and we had really solid yeast counts. generally though we ran 2 shifts and put out 60 and then followed with a 30 or another 60 depending on the tank we were filling into.


ALSO I AM BY NO MEANS AN EXPERT lol just a little more experience then average.
 
I would just pitch the whole thing. In 24 hours you are unlikely to have fermentation started. Even if it had, not gonna matter.

I make a Belgian dark where I wait to add the candi sugar until fermentation is half over.
 
Perfect, all made sense what you said. I have OCD when it comes to cleaning and sanitizing my brewing equipment, so will definitely be clean stuff for day 2. I am relieved - thanks!

So would you be pitching yeast according to the volume of both batches or just for the first? I would assume I need to add nutrients for both batches.
In my opinion, you can pitch the yeast just for the 25 liters. That first batch is essentially a 25 l yeast starter. But an overpitch would not be harmful, just wasteful in my opinion.

As for nutrients, I suggest to use 50 l worth, but even with no nutrient it will be ok, so also 25 l worth is ok.
 
In my opinion, you can pitch the yeast just for the 25 liters. That first batch is essentially a 25 l yeast starter. But an overpitch would not be harmful, just wasteful in my opinion.

As for nutrients, I suggest to use 50 l worth, but even with no nutrient it will be ok, so also 25 l worth is ok.
So @Donoroto , basically whatever! Hahahah
 
I was thinking that maybe you could do a much thicker mash and dilute afterwards.
Factor 2 might be a bit too much though.
Although, maybe.
Never done it your scale, but I start with 7.5 litre water, and have made 12-13 litre beer by diluting...
 
I was thinking that maybe you could do a much thicker mash and dilute afterwards.
Factor 2 might be a bit too much though.
Although, maybe.
Never done it your scale, but I start with 7.5 litre water, and have made 12-13 litre beer by diluting...
I have done this too. I mash double grain bill, boil and dilute in the fermenter. I can only do it for beers 1.050 or lower.
 

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