# Easy Yeast Top Cropping



## Wolfy (18/4/11)

Pictures of the Burton Union and more recent Firestone Union in the 'Yeast' book made me think how easy it would be to use something similar at home to top-crop active yeast.

Burton Union






Firestone Union (note the collection buckets in the background)





And what I'll call "PC Union" (Plastic Cap Union):





Due to fridge-geometry I've started to use plastic jerry cans for fermentors, rather than the typical plastic pails or barrels, they are easy to use, but it does make it a harder to see what is going on or to interact with or top crop the yeast.

By drilling a hole in the jerry-cap (slightly smaller than the plastic tubing) and then forcing the plastic tube into the hole it makes an air-tight seal.
The other end of the blow-off tube was put into a 2L glass bottle with 1L of cooled boiled water (with a cling-wrap collar to keep out any bugs).
Filling the 25L jerry with about 23L of wort seems to be the ideal target for the active yeast - at high krasuen - to be forced up the blow-off and to be collected in the bottle.

3 days into fermentation (a Bank's Mild clone hence the dark wort colour) and after high krasuen, the blow-off was removed (and replaced with cling-wrap) and the collection bottle chilled in the fridge over night:




The result is an ideal amount of clean freshly harvested ready to re-pitch or wash-and-store yeast, all with little or no effort and with very minimal risk to sanitation or any related issues.

The same could easily be done with a bucket or barrel fermentor by using a blow-off tube suitable size for the hole in the lid, and then sealing the lid well to prevent any escape of gas, yeast or wort.
Too much head-space means the yeast would not be forced out of the fermentor and too little head-space would most likely make much more of a mess.


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## _HOME_BREW_WALLACE_ (18/4/11)

What a brilliant idea! Its great that you dont have to handle the krausen at all, reducing any possibility of an infection.

Was this a trial and error thing with volumes in the fermenter to get it to spew out of the blow-off tube?


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## haysie (18/4/11)

Exactly what I do with my better bottle fermenters.. easy peasy


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## ekul (18/4/11)

haysie said:


> Exactly what I do with my better bottle fermenters.. easy peasy



How does the yeast go when you fire it up? Have you had any infections? My fridge, even when clean, is a little gross and wet, i think if i did this it would be asking for infections. 

I like the idea of fermenting in jerry's though, i reckon i could get 4 of them in my fridge. *grabs tape measure*


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## _HOME_BREW_WALLACE_ (18/4/11)

ekul said:


> I like the idea of fermenting in jerry's though, i reckon i could get 4 of them in my fridge. *grabs tape measure*



I get 3 of them in my fridge, and i reckon i could get a V8 juice bottle in front of each of them now.


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## haysie (18/4/11)

ekul said:


> How does the yeast go when you fire it up? Have you had any infections? My fridge, even when clean, is a little gross and wet, i think if i did this it would be asking for infections.
> 
> I like the idea of fermenting in jerry's though, i reckon i could get 4 of them in my fridge. *grabs tape measure*



Mine have come out picture perfect.. the same as Wolfy posted. My fridges most of the time have some mould and bits cut out here n there, real eyesores for the perfectionist. Infections? none, the yeast fires up immediatly when pitched, afterall its the most healthy yeast blowing out. Just make sure a good glad wrap/foil seal on your receiving flask and clean and sterilise the blow off tube well for next time.


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## Wolfy (18/4/11)

_WALLACE_ said:


> Was this a trial and error thing with volumes in the fermenter to get it to spew out of the blow-off tube?


Trial and error and depends on the yeast/wort, etc, but around 22-24L of wort in a 30L container seems to be a good staring point.
22L of stronger wort and a different yeast in a 30L round fermentor was enough for it to crawl up and stick itself to the lid, as you can on the top here:






haysie said:


> Exactly what I do with my better bottle fermenters.. easy peasy


Even easier with better bottles or US-style glass fermentors, I just didn't think too many people around here used them. 


ekul said:


> How does the yeast go when you fire it up? Have you had any infections? My fridge, even when clean, is a little gross and wet, i think if i did this it would be asking for infections.


I wipe down the inside of the fridge with bleach, but the good thing about collecting the yeast this way is there is no contact with the fridge or outside air, the system is enclosed, and since the yeast is forming CO2 it's pressurized from the inside so that should help keep anything out. I think opening the lid of a round fermentor, to stick a spoon in and manually top-crop it inside my fridge would be more of a risk than doing it this way.


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## ekul (18/4/11)

Wolfy said:


> I think opening the lid of a round fermentor, to stick a spoon in and manually top-crop it inside my fridge would be more of a risk than doing it this way.


this is exactly why i haven't done any top cropping to date. Inside the fermenting fridge is a little suss (i do clean it though) but the outside has all sorts of shit floating around probably. My fermenting fridge sits right next to the lawn mower, and for somer eason i've always assumed that this would be crawling with nasties.

I think i have a jerry can sitting there, i might give this a go. I'm still going to measure up the fridge to see how many jerries i can get in there. If i could have 4 in there that would be great because i could keg half and bottle half for aging. I prefer the beer from bottles but its such a hassle.


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## felten (18/4/11)

Brilliant, I was thinking about top cropping for my next 3 beers but this is definitely a better option, just need a proper lid for my betterbottle.


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## haysie (18/4/11)

Wolfy, you need some brew space!
Great post/thread :icon_cheers: , I have mentioned the same before but pictures are easier to read. So bloody easy to crop this way.


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## Punkal (18/4/11)

Very nice... Top cropping was on my to do list it has now been replaced with this method...


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## jakub76 (18/4/11)

There's a related project build on the BYO website.

http://www.byo.com/stories/article/indices...system-projects

Fairly elegant take on the Burton Union theory. It also includes a list of suitable, top cropping yeast strains.


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## Wolfy (18/4/11)

jakub76 said:


> There's a related project build on the BYO website.
> 
> http://www.byo.com/stories/article/indices...system-projects
> 
> Fairly elegant take on the Burton Union theory. It also includes a list of suitable, top cropping yeast strains.


Very elegant, and it returns the wort back into the fermenting beer, which (I think) is part of the 'union' system - it just looks a bit more complicated to build.


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## felten (20/4/11)

Wolfy how do you calculate how much yeast to repitch? I've been searching about this for a while and there is plenty of info on how and when to top crop, but very little on calculating the amount to repitch based on gravity/volume. 

I seem to remember the pitching rate calc site had a help section that may have dealt with the settings for top cropping, but the website is updated and that has disappeared.


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## Wolfy (20/4/11)

felten said:


> Wolfy how do you calculate how much yeast to repitch? I've been searching about this for a while and there is plenty of info on how and when to top crop, but very little on calculating the amount to repitch based on gravity/volume.


MrMalty still has the 'Repitching from Slurry' option ... else I'll have to find the page in the 'Yeast' book which estimates the amount of slurry you need.
When top cropping the 'Non Yeast Percentage' should be 0 and 2.5-3billion/ml is the 'Concentration' I assume.


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## felten (21/4/11)

Sounds like a good place to start at, thanks.


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## Yob (4/11/12)

Hopy you dont mind Wolfy.. for those using barrel type FV's I made this little thing last night.. I rekon it will work quite well

Ive cut off a bit of a funnel and that will go on the inside of the lid (with o ring replaced) and attach to the blow off tube.







The hose fits very snug into the jar lid







I should be able to significantly reduce the length of the hose but the funnel attached very well indeed 

:icon_cheers:


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## stevemc32 (12/11/12)

So this is my first attempt at top cropping and in fact the first time I've used a blow off tube for any brewing.

A couple of quick questions. Firstly, does the head space really matter at all, I just moved the end of the tube down into the krausen and it started to push it through the tube. Is this ok and is there an ideal depth inside the krausen to be taking the yeast.

Secondly, I've had a bit of a spill over through the foil cap on my collection bottle. Should I change out the bottle for a clean one or will the yeast still be ok.




It's a Belgian Pale Ale using wy3787 Trappist High Gravity and I really need to be able to save some as my last test tube of this yeast popped it's bung and I had to throw it.


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## stevemc32 (21/11/12)

Wolfy said:


> The result is an ideal amount of clean freshly harvested ready to re-pitch or wash-and-store yeast, all with little or no effort and with very minimal risk to sanitation or any related issues.



Seems I stuffed up by not reading the above sentence enough times... I collected 4 test tubes full of healthy looking yeast for storage but neglected the wash stage and all four of them spat their bungs and made a mess in the fridge. I assume they continued to ferment the very small amount of wort that was collected with the samples.


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## Nick JD (22/11/12)

Why top crop?


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## mje1980 (22/11/12)

For uk ale yeast it works well, and is very healthy. Also, no trub from the bottom of the fermentor. Half a cup of top cropped yeast pitched fresh is plenty. It "seems" to carry over yeast flavours better too ( esters etc). I can't say for other yeast strains as I usually do it for the uk strains.


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## Macdoc (22/11/12)

Is cropping yeast a way of getting your yeast to go further? So say you were brewing a Pale Ale with US-05, you siphon off some of the Krausen and now you've got another batch of US-05?


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## mje1980 (22/11/12)

Yes kind of. The big thick yeasty foam on top of fermenting beer is super healthy yeast, without a lot of crap that falls to the bottom. You don't need a lot, and if you have a sanitised ladle ( i use ss ), you scoop some out, and you can pitch straight into another beer. I dump into a sanitised jar ( one fermentor ), then when the previous batch is done, take it out of the fridge, dump into the fermentor, and splash the new wort on top. It gets going quickly, and i think that more yeast character goes through to the beer, compared to pitching onto a whole yeast cake. You can also keep in the jar, and if you don't use straight away, make a starter with it next time. 

Some strains are more suited to it than others. Some of the UK strains get a really thick, tan coloured creamy mousse like krausen. This is the goods!.


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## micblair (22/11/12)

Yeah a nice way of getting your yeast cost down and kicking off a fermentation with not too much effort at all provided your sanitation skills are good. I still get nervous doing it though as the risk/cost of infecting a batch costs a lot more than a smack pack or dry sachet of yeast.


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## Macdoc (22/11/12)

Righto, so could you crop some yeast into sanitised jar with pre- boiled water in it, then put it in the fridge, wait 3 weeks for your primary to be free then create a starter and pitch into another brew a week after that. How long will the cropped yeast last in a sanitised jar? Cheers.


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## thylacine (23/11/12)

micblair said:


> Yeah a nice way of getting your yeast cost down and kicking off a fermentation with not too much effort at all provided your sanitation skills are good. I still get nervous doing it though as the risk/cost of infecting a batch costs a lot more than a smack pack or dry sachet of yeast.



Top cropping without opening the fermenter:

Pic shows fermenter screw on lid with grommets installed, cut down bottling wand tubes inserted into the grommets. Preserving jars come with tough durable snap-lids. 
eg. bought mine as single items at Magnet Mart. (I use a larger jar now...)

Cheers


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## Nick JD (23/11/12)

Macdoc said:


> Righto, so could you crop some yeast into sanitised jar with pre- boiled water in it, then put it in the fridge, wait 3 weeks for your primary to be free then create a starter and pitch into another brew a week after that. How long will the cropped yeast last in a sanitised jar? Cheers.



It's easier just to split the pack of yeast into 3 or 4 lots, store them and make a starter from them when you need. The advantage of top cropping is it's ready to pitch.


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## stevemc32 (26/11/12)

Nick JD said:


> Why top crop?



Nick, I didn't reply to this one earlier as I didn't really understand it until your last post above.

For me it was really just a chance to have a go at something new with the yeast as I was planning a blow off tube anyway. It didn't really work that first time with all the bungs popping so I'll have to wash and store some slurry from this batch to ensure I keep a sample of the strain. This batch was the last of the 4 way split from my original smack pack.


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