Dry Hopping and oxidizing Question in conical fermentor.

[telemarkus]

Hey all;

I am brewing a West Coast IPA today and i have quite the dry hopping schedule for it.

I had a question to see what people thought and their methods.

I am always worried about oxygen getting into the fermenter after fermentation is complete and I have to open it multiple times for adding the dry hops a number of times. Does any one have any suggestions to avoid the air getting in/oxidising the beer issue? I keep meaning to ask our local brew co how they do it on their big conicals. This is the same regardless in my conical or in a classical carboy. One suggest was to add the dry hops right before fermentation is complete, but with this hop schedule I have to add some after primary fermentation is over.

Thoughts, techniques?

Appreciate it. Brew on.

Markus

[brewfun]

Are you controlling temperature? Cooler fermentation holds more CO2. When you dryhop, that CO2 comes out and will purge the headspace pretty quickly.

Commercially, we get the hops in as fast as we can and close up the very small port. If we don't, hilarity ensues! https://www.youtube.com/watch?v=Zn2oQR5p_fc

Even an 8" manway door is a relatively small opening compared to the total surface area. CO2 is heavier than air, so it doesn't come tumbling out when a port is opened at the top. If you can dryhop without taking off the whole lid, all the better. 

For multiple dry hop schedules, you can take a CO2 hose and set it for a slow flow that you point into the headspace as you dryhop. That will keep a blanket on top of your beer. Obviously, you can add the hops very gently to avoid churning and splashing.

[Oginme]

I've generally not been concerned with oxygen infiltrating my carboy with dry hopping.   When I don't dry hop during active fermentation, I control the temperature and raise it a few degrees a few hours before every dry hop addition.  This stimulates the yeast in suspension and they will generally take care of any oxygen that comes in with the hop pellets.  Like Brewfun stated, I keep the opening small and add the hops quickly.  I like his suggestion about helping to purge the air space with CO2 when adding the hop pellets.

Brewfun, I am not sure I would have termed it 'hilarity' for that video.  The tear in my eye was from watching that much beer hit the drain!

[telemarkus]

Hi guys;

thanks for the reply. Yep temperature is being held. Using Wyeast 1217 (west coast) and holding at the low end of its range at 64F. I'm using a Blichmann fermenator so there is a smal port to throw the hops into. the thing is to get that open you have to pull the pressure release valve to purge the excess CO2. there is where my problem is. because then i pressure release and throw hops in but i know air is in there then. getting CO2 back in to the fermentor is a problem then too because even if i pump CO2 in i would have to do it through the blow off valve, which once disconnected to reconnect the blow off tube I again would have let a lot of the CO2 out (but would just hope that enough remains in there as it is heavier than air before i reconnect the blow off tube. I guess there is no perfect solution ?

Thanks again!



markus

[Laura Houra]

Under professional brewing ( brewing barrels), there is generally a device installed above the fermenter that specially used for dropping hops. It could help to maintain the pressure inside of the fermenters.  See below picture. The hop should be added into the small hopper firstly, closed the end cap, then opening the bufferfly valve to let the hop goes into the fermenter. The air inside of the fermenter will not run out as the whole dry hopping process is sealed.

Laura Houra
Shandong Tiantai Beer Equipment Co., Ltd
trade@cnbrewery.com
www.microbrewerysystem.com
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