Dessert dirty soda

Our build: The French Vanilla Business — French Vanilla and vanilla ice cream over Cherry Coke.

Open this in the Dirty Soda Maker lab →

Ingredients

How to make it

  1. Get the Cherry Coke properly cold — Fridge-cold, 38 °F / 4 °C. Not "cool" — cold.

    CO₂ solubility follows Henry's law: it falls off a cliff as the liquid warms. Pouring at room temperature instead of fridge temperature throws away about 41% of the carbonation before you have even picked up the cup.

  2. Fill with nugget / pebble — About 52% of the 32 oz cup.

    Ice does two jobs and one of them is working against you. Nugget / pebble has far more surface area than a plain cube, so it chills fast but also scrubs CO₂ out of solution and melts quicker — this build will be 22% melt water after ten minutes.

  3. Syrups and acid go in first — 8 pumps French Vanilla

    Dense syrup sinks. Putting it in first means the incoming soda does the mixing for you — you get an even drink without a spoon, and stirring is what knocks the bubbles out.

  4. Pour the Cherry Coke down the side — 14¼ fl oz — tilt the cup and run it down the inside wall.

    Every bubble needs a nucleation site to form. Pouring onto a flat wall gives it far fewer than dropping soda through open air onto ice, which is why a careful pour keeps its fizz and a splashy one foams over. Leave about 1.9 fl oz of headspace.

  5. Add the cream — 1 scoop Vanilla Ice Cream · 1 fl oz Heavy Cream

    At pH 4.34 this is comfortably above casein's isoelectric point of 4.6, so the dairy is stable. Pour it however you like — down the side gives you the nicer marbling.

  6. Drink it within 12 minutes — Straw in. No stirring.

    Past 12 minutes this build drops below 60% of its starting carbonation and the melt water has moved the sugar-acid balance somewhere you did not ask for. Dirty soda is not a sipping drink — the recipe is only true for a little while.

Why it works

Sugar–acid balance

Brix:acid of 204 is dessert territory. Delicious for half a cup, heavy by the bottom of it.

Free sweetness

The cherry and vanilla aroma here makes this taste sweeter than its sugar content alone would predict. Congruent smells and sweet taste get bound together in perception, so the nose does work the sugar would otherwise have to. It is the cheapest way to cut sugar without anyone noticing.

Why there is salt in your soda

Sodium is a selective suppressor: it flattens bitterness hard and nudges sweetness up, at concentrations far below the level where you would call the drink salty. This is the oldest trick in the kitchen and it belongs in a cup as much as on a plate.

Carbonation

Starting at 2.7 volumes of dissolved CO₂. Bubbles are not just texture — dissolved CO₂ is converted to carbonic acid on the tongue and detected by the *sour* receptors, so fizz genuinely adds tartness. As it goes flat this drink will also taste sweeter and rounder. You have about 12 minutes.

Dairy is safe here

Final pH is 4.34, above the 4.6 isoelectric point where casein clumps. Nothing is going to break on you.

How it changes in your hand

After ten minutes it is 22% melt water. Sweetness drifts from 80 to 75 and fizz from 35 to 29. This build holds up well.

Make it your own

This build came out of Dirty Soda Maker's flavour model, which predicts how sweet, tart, creamy and fizzy a drink will taste from the actual chemistry of what goes in it. Move the sliders and it will work out a different recipe that hits your numbers.

Build your own →

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