New One on Me - Any Idea(s)

[bearpaw8491]

I started a 5 gal batch of Apfelwein 7 days ago using an established and proven recipe. The fermentation is active appears normal; however, the other day, I noticed a layer of foam on top of the must - nothing of concern. About an hour later, the foam was gone. This pattern of appearing and disappearing foam has continued cycling about once per hour.


I have no reason to believe there is a problem but have never witnessed “Mystery Foam” in all my wine making years. Any ideas?

Foam



No Foam

 

[winemaker81]

Mother Nature and Dionysus got drunk and are messing with you.

I don't have any idea of the reason behind it, but agree there is not likely a problem. I've had foam cycle on and off before, but not that rapidly.

 

[BigDaveK]

My current wine in primary is doing the same thing. If it weren't for the sound of the bubbles you'd think it was stuck. Then a light foam forms that goes away but comes back. Temperature? Barometric pressure? Protein? Carbs? Position of the moon? Got me!

 

[Rice_Guy]

Foam is the release of gas in a media which has molecules that stabilize it, ,,, (like soap). If there isn’t anything to stabilize it, we just have bubbles that pop. In your situation I would wonder about changes in air pressure, ex. gusts of wind that changes pressure.

 

[bearpaw8491]

Mother Nature and Dionysus got drunk and are messing with you.

I don't have any idea of the reason behind it, but agree there is not likely a problem. I've had foam cycle on and off before, but not that rapidly.

Great idea! That was gonna be my second guess!!!!!!!!!!!!!

 

[bearpaw8491]

Thanks Bryan, Dave, and Rice Guy. For the first day or two of fermentation, you could easily see the CO2 rising and popping at the surface so I'm pretty sure there was nothing in the carboy that could have provided a film to stabilize the bubbles like Rice_Guy mentioned. I wonder if such a substance could have be generated from the actual fermentation process although I've never seen nor heard of such a thing even in some of the more viscus musts I've used. I hadn't considered atmospheric changes. We've been under the control of a large high pressure system for the past week ( and should continue thru most of the week) so extreme pressure changes are unlikely.
All in all, my money's on Bryan's idea above!!! Just goes to show ya that there's something to be leaned on every ferment. Will keep you posted on parameters/ changes when I rack.
Thanks to all.

 

[winemanden]

Just guessing here. I think it may be that a thin layer of solids builds up towards the bottom, then when the CO2 pressure gets too strong it releases it with a whoosh!

 

[Rice_Guy]

. I wonder if such a substance could have be generated from the actual fermentation process although I've never seen nor heard of such a thing even in some of the more viscus musts I've used.

well of course they make substances, commercial yeast are selected for a low foam trait usually, ,,, most yeast will produce some glucans ,, the worst I have run was Malurvin B a selection that metabolizes malic acid and unfortunately created as much foam volume as must. Today I am scratching my head with an apple creating foam. Is it apple pectin causing foam or is the high glycerol production on that yeast selection?

 

[bearpaw8491]

well of course they make substances, commercial yeast are selected for a low foam trait usually, ,,, most yeast will produce some glucans ,, the worst I have run was Malurvin B a selection that metabolizes malic acid and unfortunately created as much foam volume as must. Today I am scratching my head with an apple creating foam. Is it apple pectin causing foam or is the high glycerol production on that yeast selection?

We may have a winner! Hadn't considered foam production from the yeast. I used an old - really old! - packet of Montrachet which has a moderate to high foam production- if I remember correctly- and maybe glycerol too. Are Malurvin B and Montrachet related? Since this is Apfelwein and malic acid was added to the juice during production (according to the ingredient list), could be a key factor. Not sure what would account for the cycling of foam coming and going.
At any rate, fermentation continues without noticeable problem(s).
Film at 11