CO2 coming out of solution in siphon

[nzbrew]

Hi all

Siphoning an IPA from carboy to bottling bucket today, I changed my usual process and decided to filter out the hops bits (it hadn't fully settled out).

I put a small square of swiss viole over the end of the auto-siphon (there is an push on bit that goes over the end of the autosiphon so I jammed it in between).

Strange thing happened - the CO2 was appearing in bubbles in the siphon tube - in a big way! It's the first time I've tried to filter the hops, so not sure if this is a common occurrence????? It freaked me out so I stopped and removed the 'filter'. Back to normal then with a bubble free transfer.

In the photo you can see the bubbles appearing, then becoming 'foam' further down the tube.

Is this an expected result from the filter?

 

[Nosybear]

I don't know about it being likely, has never happened to me but if it's coming out of solution and you're siphoning from the bottom of the beer, it's CO2, and harmless. My guess is the screen is slowing the flow enough that the bubbles have time to form and grow.

 

[nzbrew]

Definitely co2, siphoning from well down in the beer. Your explanation makes perfect sense.
If the co2 was no longer in solution (released to atmosphere in the bottling bucket) would it affect the priming sugar calculation? That relies on a certain amount of dissolved co2 (using temp to adjust).

Interested to see what you think - and thanks for your reply!

 

[Hogarthe]

I think the filter is acting as nucleation sites, giving the co2 places to grab onto and form bubbles. like the little bumps the Sam Adams pint glass has on the bottom. since you stopped using the filter, your priming should be ok. if you used it for the whole transfer it might release enough co2 to need to adjust your priming sugar amount. I wouldn't know how much to adjust it by though, as I have no idea how much co2 you would lose.

 

[Nosybear]

Either way, it's CO2 coming out of solution. The unprimed beer may be a bit supersaturated, accounting for bubble formation when the beer flows through the racking cane. As far as priming goes, the solution will still be saturated even with the gas escaping so the bubbles shouldn't affect priming calculations but you can always put a very small amount of additional sugar in - no one can tell the difference between 2.5 and 2.6 vols....

 

[Ozarks Mountain Brewery]

could be because the airlock had a blockage or krausen sealed the top layer keeping c02 down, Ive had that happen before, all its doing is carbonating the beer while fermenting, should have taken longer than normal it tends to slow fermentation down, taste the sample to see how much its carbed already but don't think it will change anything! but since I only keg and bottle from the keg I just usually carb as normal with c02