Pressure my cans through carbonation?

[esiney]

Hi,

I am making a carbonated flavoured water. My cans are not strong to touch when seamed (squishy). Some are firm. I carbonated using a Blichmann Quik Carb in a Korny keg. I used a beer gun to fill the cans from the Korny keg. I then seamed the cans. The cans are not firm apart from the odd one. Is there a reason for this? Am i missing something? How can the beer cans feel pressurised?

Thanks,
Ed

 

[Golddiggie]

IME, you'll lose carbonation when filling cans with the beer gun. Even with a counter pressure filler, I carbonate on the higher side than I'll serve from keg since I know I'll lose at least a little to the process.

Depending on what can sealer you're using, you could also have bad seals on the soft cans. That's why I went from the manual Cannular to the Pro version. I've had zero bad crimps on the cans since the change.

How long are you letting your Corny keg carbonate? The Blichmann item says it will be "90% carbonated in one hour". I'd take that with about a pound of salt.

 

[esiney]

Thanks for the reply.

I cool the flavoured water down to 33 farenheight and use 22 psi of co2 through the QUik Carb for 45 mins - 1 hour. The carbonation level is good as I'm not going for ultra fizzy like Coke.

I use the October manual canner. I have canned a few thousand Still versions and no problem with the seams so the canner machine is good.

I connected the beer gun and started filling the cans straight away (should i let the keg rest to reduce the fizz?). I released some of the pressure from the Korny keg from the pressure relief valve on top and then set the regulator to as low as possible to push out the flavoured water from the keg into the cans. The fizz levels were strong, having to refill the cans 2/3 times after the fizz reduced to fill a full can. I then seamed the lids. Some cans had enough pressure in the cans but then others had very little. From rotating the cans, not all of them are full to the top. The 3/4 full ones seem to be more squishy than the full cans. I assume that's another reason as to why those cans were squishy?

Ultimately I need to find out why some cans are squishy as I want to get all the cans to a decent strength when you grip them.

Thanks in advance for any help

 

[RolandD]

You're losing a lot of carbonation through the transfer process. You'll need to experiment with how much to over carbonate prior to transfer to hit the level of carbonation you're looking for once canned. Giving it a day or two to rest and really absorb the CO2 prior to canning will help. As will chilling the cans before filling them. Make sure they are the same temperature as the liquid and this will reduce the loss of CO2 as they are filled.

You might also try filling the cans while they are still wet with chilled Starsan. A dry surface has more nucleation sites than a wet surface.

 

[doug293cz]

All the "fizz" during canning is your carbonation leaving the beverage. The more fizz, the more carbonation you lose. You should try to get your equipment and process tuned, so that you can fill a can in one pass, with no more than 1/4" foam on the top. You may need longer tubing on your beer gun, since your carb level is higher than typical beers. What kind of tubing do you have on the beverage line to the gun, what is the tubing ID, and what is the line length?

Also, you should probably fill one can and seal immediately, rather than fill several, and seal a bunch at once (if that's what you're doing.) The longer a can sits unsealed, the more carbonation it can lose.

Brew on

 

[esiney]

Thanks for both replies Roland & Doug. After I carbonate the Corny keg at 23 psi, I go straight into canning and thus the excess foam (3/4 pulls of the gun to fill the can for each time to allow foam to reduce).

What i'm thinking is the serving pressure of the keg is still at 23 psi as I have reduced the regulator down to 10 psi but the pressure in the keg is still high for the first few cans. I might try bleeding off all the pressure in the keg and then apply only 2/3 psi to the keg (got those figured online) so the pressure in the keg is really low and thus will help reduce foam. Would this be correct?

In relation to pressure of the cans, If I cap on foam and seam quickly, should the can be strong enough to the touch or have weak walls? I don't want to add LN2 to the headspace as I will pasteurise the cans and I have added LN2 before and the cans burst under pasteurisation

 

[doug293cz]

Thanks for both replies Roland & Doug. After I carbonate the Corny keg at 23 psi, I go straight into canning and thus the excess foam (3/4 pulls of the gun to fill the can for each time to allow foam to reduce).

What i'm thinking is the serving pressure of the keg is still at 23 psi as I have reduced the regulator down to 10 psi but the pressure in the keg is still high for the first few cans. I might try bleeding off all the pressure in the keg and then apply only 2/3 psi to the keg (got those figured online) so the pressure in the keg is really low and thus will help reduce foam. Would this be correct?

In relation to pressure of the cans, If I cap on foam and seam quickly, should the can be strong enough to the touch or have weak walls? I don't want to add LN2 to the headspace as I will pasteurise the cans and I have added LN2 before and the cans burst under pasteurisation

Reducing the pressure to fill isn't really the answer. The beverage is in equilibrium at 23 psi CO2 pressure. If you reduce the pressure when filling, then CO2 can start to break out in the transfer line, so foaming starts before the beverage even gets out of the fill gun. The right way to do things is get the transfer line long enough so that the flow resistance along the line is equal to the CO2 pressure in equilibrium with the carb level. This prevents CO2 breaking out of the beverage in the line. The older standard vinyl, 3/16" ID serving line has a pressure drop of about 1 psi/ft, so you would need somewhere around 23 ft of line. The newer, and better, EVA barrier tubing has an ID of 4mm, so has a resistance per foot about twice that of 3/16" vinyl. To find the length of line you need with your beverage line, and carbonation pressure, use this calculator.

Brew on

 

[esiney]

Cheers for that. I am going to try the TapCooler Nanocanner pressure filler. This seems to pressurise the can to prevent foaming. I will apply what you suggested too with the type of beer line. I will let you know how I get on with it. If I don't foam, then I know that filling an unpressurised (open) can with a beer gun was not helping

 

[doug293cz]

Cheers for that. I am going to try the TapCooler Nanocanner pressure filler. This seems to pressurise the can to prevent foaming. I will apply what you suggested too with the type of beer line. I will let you know how I get on with it. If I don't foam, then I know that filling an unpressurised (open) can with a beer gun was not helping

The TapCooler Nanocanner looks like the best available solution to your problem. If I had known about it, I would have recommended it to you. Thinking about your problem, I envisioned a tool that is basically the same as the Nanocanner (somebody was way ahead of me.)

With the use of counter pressure filling, the length of the beverage line is no longer critical, as the counter pressure serves the same purpose as a longer line. I would still recommend the EVA tubing for it's superior O2 barrier properties.

Brew on

 

[Bobby_M]

You should definitely be letting the keg sit undisturbed for several hours or overnight. You'll want to get your beer gun, the water, and the cans down to near freezing. I use a bucket of sanitizer with a bunch of ice packs. You may also want to use 20 feet of the 4mm ID EVA barrier tubing.

 

[esiney]

Cheers Bobby. I'll let the keg sit for a few hours in the fridge.

I'm waiting on the Tapcooler pressurised can filler which would be representative of a large scale carousel can filling line so hoping that will help, I'll send an update when it arrives