Keeping the bubbles in sparkling gelatin desserts

As Chris says, its to do with the setting time of the gelatine vs the bubbly.

Ensure all of your containers are chilled (maybe even frozen? - I put mine in 3/4 hours before making the actual dish) before you add the (chilled) champagne and get it into the bottom of the fridge as quick as you can.

I suspect though cannot prove also that a smaller container (I use wine glasses or similar) will work better than one large dish (trifle sized etc).

Most guides I find report various degrees of success with carbonated drinks, but most agree that Club Soda is the best performer.

You may want to use Club Soda instead, or try a mixture.

It really has to do with the amount of time between the addition of the champagne, and when the gelatine sets, thus capturing a bubble. Champagne releases gas fairly quickly, and gelatine sets slowly.

I would probably do the main preparation with a comparable white wine, and refrigerate it until nearly set, and then add the soda water for sparkle.

Ever notice that if you squeeze all the air out of a partially full soda bottle, it doesn't go flat? Me thinks the negative pressure keeps the carbon dioxide dissolved (which is odd when compared to the usual positive pressure we experience when opening a soda bottle). As such, you might try a food vacuum system (e.g. Food Saver) to apply negative pressure to the container in which you prepare the dessert. Be careful during preparation, of course, to not agitate the liquid too much, or it may go flat before you're done.

Post back your results. I'd like to know, too.

"Negative pressure" doesn't keep carbon dioxide dissolved, and carbon dioxide doesn't only dissolve like other gases in water, it changes with the help of water and pressure to carbonic acid (H?CO?).

The best way of ending up with a sparkling dessert is re-carbonating it. That might be not as pretty (as you end up with a gel) - but it will be effective (and probably delicious). Add your jelly into a cream siphon (or Soda Plus) and carbonate it.

If you wait for some time, you will end up with a perfectly carbonated jelly.

If you really would like to have a set dessert, which is carbonated, you can add dry ice into a container (e.g. cooler box) with the jelly and wrap clingfilm to have it almost air tight. However you would need to wait longer (over night), until it is properly carbonated.

What you really need is a container with a cover. Fill it the brim with unset but carbonated gelatin (add the carbonated water after the gelatin is chilled as much as possible, then cover and finish the gelling process.

Jello brand gelatin in the USA years ago had a recipe. The soda was added to partially set gelatin. But I cant remember the details so I cant reproduce this I did years ago. Picture wont upload, sorry. But looked great in clear glass bowl (4cups)