Volcano Foaming. Why?

[jpftribe]

My OCD has officially kicked in and I was forced to purchase two more pails of italian grape juice. Like every other bucket I purchased, they were in full fermentation before I could pitch the yeast. I had to roll down the windows of the car to air out the CO2 on the hour ride home.

I mixed a slurry of RC212 and go ferm. I dumped the pails into 7.9 gal fermenters after the last batch foamed all over the floor when I fermented in the pail. Wasn't making that mistake again.

I pitched the barolo and gave it a quick stir and it foamed up to the top of the fermenter. The amarone erupted violently without even a stir, all I did was pitch the slurry. I was lucky not to lose any of it.

What's the science behind this? Can anyone point to some semi-light reading on this? I get there's a lot of CO2 trapped, but what about the slurry can cause that violent of a release?

 

[Johnd]

My OCD has officially kicked in and I was forced to purchase two more pails of italian grape juice. Like every other bucket I purchased, they were in full fermentation before I could pitch the yeast. I had to roll down the windows of the car to air out the CO2 on the hour ride home.

I mixed a slurry of RC212 and go ferm. I dumped the pails into 7.9 gal fermenters after the last batch foamed all over the floor when I fermented in the pail. Wasn't making that mistake again.

I pitched the barolo and gave it a quick stir and it foamed up to the top of the fermenter. The amarone erupted violently without even a stir, all I did was pitch the slurry. I was lucky not to lose any of it.

What's the science behind this? Can anyone point to some semi-light reading on this? I get there's a lot of CO2 trapped, but what about the slurry can cause that violent of a release?

Your slurry isn't really liquid, but a suspension of millions of little particles, each one of them a nucleation site for CO2........volcano.

 

[Scooter68]

To some extent I would guess that having your must comprised of very fine material - like a blenderized fruit or fruit that has broken down to a high degree - THAT would contribute to this sort of volcanic fermentation. All those particles are capturing or being captured by CO2 and rising to the top. When a lot of CO2 remains captured and cannot escape or does not release from those particles you have the fountain / volcano.

So a coarser fruit mash or bagging the fruit in a fine mesh bag could help prevent this. That's why our fruit bags have to be punched down - to release the CO2 and get the fruit back into the liquid.