Force Carbing (shaking) vs ?Burst? carbing?

[Rob2010SS]

I recently got into a "debate" with someone on the topic of force carbing your kegs, where you shake or roll them, vs what I'm calling burst carbing - where you hook up the CO2 at a high PSI like 40-45 and let it carb in a day or so.

I was explaining to the individual that although I've never done it, I don't like the idea of force carbing. My logic is that we avoid shaking the fermenter vigorously after fermentation has taken place, we avoid splashing when transferring to the keg if doing open transfers, we don't shake a bottle of beer before opening it, why would you want to shake the sh** out of a keg to get it to absorb CO2 faster? (I get that before being in a keg, you don't want to do it because of oxygen ingress...)

The individual got a little defensive and told me that the carb method I've been using - hooking up 40-45 PSI of CO2 for a day - is just as "bad", or maybe MARGINALLY better than shaking the keg. He explained that by hitting it with that high of PSI, your likely going to cause foaming and you're going to strip away aromas from the beer. He also said you'll break down protein bonds in the beer forcing in that much CO2 that fast.

I'm not saying he's wrong, but I've never heard that. I've heard of lots of people on this forum using the "burst" method. Anyone have any literature or sources that confirm or contradict what this individual is saying?

 

[mongoose33]

All you're doing with shaking the keg is increasing the surface area into which CO2 can be absorbed.

If you shake a keg at the intended pressure, I can't see anything about that which would be bad, other than shaking up sediment in the bottom which now needs to settle again.

If you shake a keg at high pressure, you're taking a risk that you'll overcarb it. Don't ask me how I know.

If you (using your term) burst carb by setting at a high psi and waiting a prescribed period of time...well, you're offsetting the smaller surface area with higher pressure.

I can't see where one is necessarily going to produce a better outcome, other than speed and the sediment issue.

 

[Rob2010SS]

All you're doing with shaking the keg is increasing the surface area into which CO2 can be absorbed.

If you shake a keg at the intended pressure, I can't see anything about that which would be bad, other than shaking up sediment in the bottom which now needs to settle again.

If you shake a keg at high pressure, you're taking a risk that you'll overcarb it. Don't ask me how I know.

If you (using your term) burst carb by setting at a high psi and waiting a prescribed period of time...well, you're offsetting the smaller surface area with higher pressure.

I can't see where one is necessarily going to produce a better outcome, other than speed and the sediment issue.

Would you say that either of these methods would produce a different outcome than the low and slow, set it and forget it method where you let out carb up over a week or two? Or do you think you'd get the same outcome with any of those 3 methods?

 

[day_trippr]

Perhaps the point was macerating "foam once" proteins whether by shaking or blasting CO2.
I would expect the former method would be much worse than the latter...

Cheers!

 

[Vale71]

He explained that by hitting it with that high of PSI, your likely going to cause foaming and you're going to strip away aromas from the beer. He also said you'll break down protein bonds in the beer forcing in that much CO2 that fast.

Your friend is full of it, and I don't mean beer.

Ask him where the aromas are escaping to from inside a sealed vessel...

 

[Rob2010SS]

Your friend is full of it, and I don't mean beer.

Ask him where the aromas are escaping to from inside a sealed vessel...

Yeah, not a friend of mine, just someone who chimed into conversation.

That's a very valid point that I didn't even think of.

 

[Bobby_M]

Force carbing is generically used to describe carbonation using external CO2 vs. refermentation. Burst carbing is also a general term for force carbing faster than set and forget including shaking, pressure elevation or both. The primary reason for different outcomes is just the likelihood of not nailing the desired carb volumes but I am suspect of foam stability for the shake method. Perhaps the point about losing hop aroma is related to the common practice of purging excess pressure after the carbing process. I would agree venting would lose some.