Low Oxygen Hopping in Secondary

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I'm getting back into brewing after a hiatus of about 3 years.

My current setup is a 30L Grainfather and a side by side fridge freezer (stand alone units), one side is a fermentation chamber (brewpi) with 30l stainless conical plus spunding valve and one side is for serving out of kegs.

I have always been pretty careful about reducing DO and really like the idea of a hop dropper that can be CO2 purged, however I only have a small threaded port for blow off on the lid and 1 1/2" TC ports on the conical. I'm considering adding a 3" TC to the lid but want a solid process for the interim.

The idea I'm having, is to;

  • Run a gas jumper line between the fermentation fridge and the serving fridge.
  • At start of fermentation's, connect CO2 (from tank @1-2 psi)? to a CO2 flushed corny keg, crack the PRV, open the top and drop a hop sock with my dry hops into the keg.
  • Reseal keg, remove CO2 and place in the fridge (serving temp) with gas line running from conical to the keg with hops then to a second keg with a spunding valve connected. The second keg is just to always keep a flushed keg handy and the keg is kept in the serving side and flushed to preserve the hops.
  • After 4-5 days (or within a few points of FG), move the keg with hops back to the ferm chamber, drop the trub from the conical, transfer under pressure from conical to the keg with hops. Cap spunding valve to start carbonation.
  • Once ferm completed, move keg back to serving fridge and cold crash.
  • After cold crash, transfer keg to keg into a CO2 flushed keg. This would either be done via CO2 from the next ferment or using bottle.
  • Force carb as required.

Any thoughts, or people doing similar?
Thats a lot of work, give it a go. See if it is worth that much care.

All I do is.

Pressure ferment snub nose conical.
@ 4 points or so off FG , open drop in dry hops .
Reseal and pressurize. C02.
Transfer to C02 flushed keg
serve from fermentor.
Easy. Serve fresh and start another.
Agree it might be a bit of a dick around for what it's worth and will likely only do it if I'm looking to get another beer going before the last one finishes and it's not going to be served straight away. I was watching a video about using fermentation CO2 to flush kegs and it got me thinking.
Using the fermentation C02 is a great idea. Just hook up from your fermenter to the liquid on the keg and put a spunding valve on the gas. You can even link in a 2nd keg to flush if you want. A lot of people on here are going to say just open the fermenter and drop the hops in but I think that defeats the purpose. Something you can try that I heard on Brülosophy is use a stainless steal mesh cannon but drill a hole in it and place it over the liquid tube in the keg. That way you can throw the hops in lose, purge, add beer then transfer off.

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