CO2 coming out of solution in transfer hose while canning.

[DowneastCider]

We ran into a very frustrating issue last week while canning. Two days in a row. Wondering if anyone here has any insight.

The problem: excessive foam while canning causing low fill heights.

The equipment: premiere stainless brite tank to goodyear 1.5" nutriflo hose (several shorter hoses linked together with clamps and gaskets) to a Cask ACS 5 head canning machine. Our glycol chiller is not setup yet so the cider was probably in the 40's while canning. The weather was dry and in the high 60's low 70's when we starting the day and got up to about 80, maybe.

The band-aid solution: adding a T at the end of of the transfer hose right before going into the canning machine. The other end of the T had a small ball valve that was cracked open (at the high point of the line). CO2 and some foam/cider was coming out of the T constantly while canning. If it was closed too much the CO2 would build up in the line and start foaming again. I found this air relief valve which I will probably get in case this happens again: http://www.dixonvalve.com/product/BARVE-G150.html

The product: hard cider. Due to the nature of cider, it barely foams, which makes this problem even more baffling. If we had been trying to can beer I doubt it would have been possible.

Other info that may be of use:
-we showed up in the morning to find the tank at just 10 psi despite the regulator set to 15psi. Cranked the regulator up to 30psi and waited a few hours for the cider to fully carbonate (the pressure relief valve opened up at some point to maintain 15psi even though the regulator was higher). We have carbonated once or twice before this way to can on short notice with no ill effects.
-we have never had a problem with using plain old goodyear nutriflo/nutriflex hosing (un-insulated) to transfer before. Not ideal due to some temperature loss, but never a problem.
-we have had gas in the transfer line before cause foam, but it was never even close to this bad (usually went away for good or at least for an hour or two when purged once by cracking the hose to bleed it off or using the T/valve solution described above).

Any ideas on what is going on? Is it just CO2 coming out of the cider? We tried playing with the pressure in the tank, hose positions (high, low, middle), changed all the coils on the Cask machine as a precaution, unplugged half of the fill coils to slow it down. None of this seemed to do anything.

Thanks
Matt

[TL Services]

Matt,

A few thoughts based on the information you've posted:

Hoses - Single-length hose would be better than several short lengths (you've probably figured this already from what you said) as anything that disrupts smooth liquid flow can/will cause gas breakout;

Temperature - Get your chiller set up. Gases always dissolve (and stay dissolved) better at lower temperatures. It may be partly that you've been borderline for a while and this time just gone over the edge;

Tank pressure - Have you investigated why the tank pressure was lower than set? Again it is possible that your CO2 level was borderline stable for 10psi pressure. Increasing the pressure to carbonate would have pushed that closer to the edge;

Pressure relief valve - can you be sure this is opening accurately at 15psi? If this is opening at higher than 15psi, then your dissolved CO2 level would be higher too, leading to an increased likelihood of breakout given half a chance;

Crash carbonating - gases take some time to truly dissolve, going through a stage of 'microbubbles' before full dissolution. Carbonating immediately before packaging, especially without good low-temperature control (ie. chiller) and pressure concerns will, again, give the CO2 every chance to come out of solution at the first opportunity.

Sorry none of those are a simple solution, but hopefully will give you some pointers as to where to look and where to concentrate improvements in control.

Hope that helps!

[Natrat]

Was the co2 breaking out in the hoses? Could you see breakout in those little hoses that go to the solenoids? If you can see that breakout, then odds are the temp was too high.
The other possibility is inadequate CIP left contaminants in the hoses that act as nucleation sites. We pack ours with sani and then run a full cip immediately before canning.

The last thing I can think of is maybe the fob solenoids were stuck? I had that happen on one head before, and taking it off and giving it a quick clean solved the problem. It can happen if the connectors on the backside of the filler manifold get wet...so that they hold the fob on for the full duration of the fill cycle. I'd dry that off and give a quick look at all the solenoids.

Also, was it a different cider? Sugar content and particulate can also create nucleation.

Good Luck!
Nat

[DowneastCider]

Matt,

A few thoughts based on the information you've posted:

Hoses - Single-length hose would be better than several short lengths (you've probably figured this already from what you said) as anything that disrupts smooth liquid flow can/will cause gas breakout;

Temperature - Get your chiller set up. Gases always dissolve (and stay dissolved) better at lower temperatures. It may be partly that you've been borderline for a while and this time just gone over the edge;

Tank pressure - Have you investigated why the tank pressure was lower than set? Again it is possible that your CO2 level was borderline stable for 10psi pressure. Increasing the pressure to carbonate would have pushed that closer to the edge;

Pressure relief valve - can you be sure this is opening accurately at 15psi? If this is opening at higher than 15psi, then your dissolved CO2 level would be higher too, leading to an increased likelihood of breakout given half a chance;

Crash carbonating - gases take some time to truly dissolve, going through a stage of 'microbubbles' before full dissolution. Carbonating immediately before packaging, especially without good low-temperature control (ie. chiller) and pressure concerns will, again, give the CO2 every chance to come out of solution at the first opportunity.

Sorry none of those are a simple solution, but hopefully will give you some pointers as to where to look and where to concentrate improvements in control.

Hope that helps!

On the hose:
Good point. Half our hose was out of commission (clamps getting re-done) which is why we used so many pieces. That will not happen again.

On the temp:
I know colder is better, but we had no issues all summer even when temps were in the high 90's for a week straight. Last week was fairly mild which leads me to believe temperature is not the main issue (but it could not hurt to be colder and our chiller will hopefully be finished soon).

On the PVV:
It is definitely working and maintaining 15psi when the carb stone regulator goes over (have had issues with that, new regulator on the way).

On the crash-carbonating:
Is there any specific time that is recommended for carbonating? We try to do it overnight usually and have had no issues with that. We have a 40 bbl brite.

Thanks for the feedback.

[DowneastCider]

Was the co2 breaking out in the hoses? Could you see breakout in those little hoses that go to the solenoids? If you can see that breakout, then odds are the temp was too high.
The other possibility is inadequate CIP left contaminants in the hoses that act as nucleation sites. We pack ours with sani and then run a full cip immediately before canning.

The last thing I can think of is maybe the fob solenoids were stuck? I had that happen on one head before, and taking it off and giving it a quick clean solved the problem. It can happen if the connectors on the backside of the filler manifold get wet...so that they hold the fob on for the full duration of the fill cycle. I'd dry that off and give a quick look at all the solenoids.

Also, was it a different cider? Sugar content and particulate can also create nucleation.

Good Luck!
Nat

Yes, I could see some breakout in the hose going right to the solenoids. I am still confused about why this time was different (we have canned warmer cider on warmer days with no trouble) but maybe it was just a confluence of events all at once.

On the hose, that is a good idea, although not sure it is the issue. We try to run a quick burst of sanitizer through the hose and filler before the cider. If we are canning on back-to-back days we leave sanitizer in the line.

Same cider.

Thanks for the feedback.