Top Cropping using Bow Off

[Owly055]

I'm considering using blow off as a way to top crop yeast. The idea is that I will fill my fermenters closer to the top than normal, and simply use a sterile blow off tube into a sterile container with an air lock. The krausen will blow through into the sterile container carrying a great deal of yeast with it.

My current top crop methodology is to use a ladle and a jar that have both been sterilized. I take my wide mouth lid off the fermenter, and simply skim the krausen, putting it into the jar. As long as there is plenty of krausen, I repeat this. It is a very effective methodology, but it involves opening the fermenter...... which really isn't ideal.

My thinking is that if I use the blow off tube and reduce the head space, I can achieve the same thing in a sterile environment..............

Has anybody tried this?? Thoughts? Ideas? It seems like kind of a no brainer to me, and it amazes me that I didn't think of it before. No yeast washing, no exposure, no fuss, no muss..... The challenge will be to figure out what I can use for a container with an inlet port for the blow off, and a place to put the fermentation lock. I'm thinking that a quart capacity is an absolute minimum for my brews that are now 2.5 gallon and will have to grow to around 3 gallons. A 2 quart jar would be better.

H.W.

 

[mkyl428]

I have thought about this too, if you do it please share results I'm curious....

What will you stick the end of the tube into Starsan? Will straight Starsan not kill yeast?

The yeast I have dumped in the past from a blow off has looked very clean, much cleaner than any yeast I have harvested.

I have also thought of connecting fermenters through a blow off tube so the blow off wound go directly into a new batch, this would require brewing pretty much back to back batches though & I'm not sure how you would figure out how much yeast is being pitched into the second batch through the blow off

 

[Kee]

This is one method:

http://karlisbeer.blogspot.com/2010_03_01_archive.html

 

[Owly055]

This is one method:

http://karlisbeer.blogspot.com/2010_03_01_archive.html

This is exactly what I intended to try.......... except that I'm using wide mouth fermenters instead of a carboy. The photos could be my own mental images..... as I tried to describe. The author and I are in agreement that the very best yeast to crop at least in a ale is the top crop.

I had intended to simply raise the level of the beer in the fermenter rather than using a drop tube as he did..... which is probably a better idea. an inverted plastic funnel projecting from the bottom of the cork in my wide mouth fermenters might be the best way to capture the krausen....... if you can visualize that. The funnel would project within 1/4 an inch or so of the surface of the wort, so whatever krausen rose within the circle of the funnel would be forced up through the blow off tube into the capture container. The more krausen you capture, the more yeast you crop.

It is nice to have an original idea.......... but better to know that someone else has tried it and it works.


H.W.

 

[Kee]

This is exactly what I intended to try.......... except that I'm using wide mouth fermenters instead of a carboy. The photos could be my own mental images..... as I tried to describe. The author and I are in agreement that the very best yeast to crop at least in a ale is the top crop.

I had intended to simply raise the level of the beer in the fermenter rather than using a drop tube as he did..... which is probably a better idea. an inverted plastic funnel projecting from the bottom of the cork in my wide mouth fermenters might be the best way to capture the krausen....... if you can visualize that. The funnel would project within 1/4 an inch or so of the surface of the wort, so whatever krausen rose within the circle of the funnel would be forced up through the blow off tube into the capture container. The more krausen you capture, the more yeast you crop.

It is nice to have an original idea.......... but better to know that someone else has tried it and it works.


H.W.

I've read about it in several places but never tried it personally. It does seem like a shame to let all that yeast go to waste. When I have top-cropped the yeast seem to have been of better quality.

 

[Owly055]

I've read about it in several places but never tried it personally. It does seem like a shame to let all that yeast go to waste. When I have top-cropped the yeast seem to have been of better quality.

I don't think there's any question that top cropped yeast is the very best. It's the live, active yeast that's actually at work when you crop it. It seems to me that blow off cropping should be the best and most sanitary method of harvesting yeast. You not only get the best and most active cells, but it can be kept completely sanitary and isolated from the environment.

H.W.

 

[rhys333]

My current top crop methodology is to use a ladle and a jar that have both been sterilized. I take my wide mouth lid off the fermenter, and simply skim the krausen, putting it into the jar. As long as there is plenty of krausen, I repeat this. It is a very effective methodology, but it involves opening the fermenter...... which really isn't ideal.

I use the same method you describe here with good success, reasoning the yeast gets exposed to the elements one way or another regardless. I like the simplicity of the ladle and jar approach, plus the option of doing an early 'dirt skim' to remove gunk and early floc yeast I don't want.

Just wondering if you're switching to blow-off because you experienced contamination, or if its just a cautionary measure. I haven't had any issues to date, but I'm curious if there are real risks I should watch out for down the line.

 

[strangebrew]

I have used top cropping with a blow off tube with great success. Also using a sanitized spoon / cup etc to pull off some wort to inoculate a starter works well too. If you are worried about contamination then top crop into a flask and grow the starter. You can confirm that your starter yeast is clean before you pitch into the new 5 gallon batch.

 

[Owly055]

I use the same method you describe here with good success, reasoning the yeast gets exposed to the elements one way or another regardless. I like the simplicity of the ladle and jar approach, plus the option of doing an early 'dirt skim' to remove gunk and early floc yeast I don't want.

Just wondering if you're switching to blow-off because you experienced contamination, or if its just a cautionary measure. I haven't had any issues to date, but I'm curious if there are real risks I should watch out for down the line.

I'm interested in using blow off cropping mainly from pure simplicity..... Just hook your rig up and let it blow until it's done blowing. As it is, I frequently take multiple crops from a single brew, pulling virtually all the krausen off several times.....just looking at how to simplify the process................ and I'm always trying something new. The possibility of having contamination problems is of course not unrealistic, though it hasn't happened to me yet.

H.W.

 

[Owly055]

In my quest for a simple way to top crop, I found pretty much what I need ........ on line of course. A rubber cork that should fit a canning jar, with two holes........ Price $4.25 each. This is a #13 stopper, and should just barely fit into a small mouth canning jar, and almost fall into a wide mouth jar.

H.W.

http://www.widgetco.com/13-2-hole-rubber-stoppers-plugs

Part Number: 7-R13-2-EPDM-RS

Top Diameter: 2-5/8" | 2.667" | 68mm
Bottom Diameter: 2-1/4" | 2.283" | 58mm
Length: 1" | 0.987" | 25mm
Hole Diameter: 3/16" | .197" | 5mm
Durometer: 55
Material: EPDM

2 Hole #13 Rubber Stoppers are 2-Hole #13 Tapered Rubber Stoppers that will plug bottles, lab vials and other openings. 2-Hole #13 Rubber Stoppers are manufactured from EPDM Rubber. Not for food applications (see silicone rubber stoppers)