Grapefruit Diet Soda - a SodaStream DIY Flavor

Introduction: Grapefruit Diet Soda - a SodaStream DIY Flavor

I received a SodaStream carbonator as a present. Once the main flavor samples and the (low-charge) CO2 canister were used up, I wondered what I could do in my own kitchen for flavorings. After seeing, I thought about what flavors I could reproduce, or at least semi-synthesize.

So, here is a recipe for a diet grapefruit soda. I call it Frasca, because a) the name is close enough to that commercial product without blatantly violating copyright, and b) just call it a tribute to the designers and manufacturers of those fine Frasca general aviation flight simulators.

Step 1: Acquire Foodstuffs and Tools


1 medium grapefruit
2 cups Splenda or other suitable sweetener
SodaStream straight-up seltzer


Hand or sieve
spatula or other stirring tool

Step 2: Make the Syrup

Juice grapefruit, pour juice through hand or sieve (to remove seeds) into measuring cup. There should be about four ounces of juice. Place juice in measuring cup, and add enough water to bring the amount of liquid to 1 cup.

Heat juice and sugar in saucepan, stirring thoroughly until fully incorporated.

Allow to cool.

Step 3: Mix and Enjoy!

Pour 8 to 12 ounces of SodaStream seltzer into a glass.

Gradually add 1-1/2 ounces of the cooled syrup to the glass. Why? There's something in the Splenda chemical makeup that causes the carbonation to flare up, and fizz-over is possible. It would take a scientist to explain it, and my wife isn't home as I write this. So, add gradually. Trust me.

Drink up!

Some Closing Notes

Yes, I know it's pink, and the commercial stuff is uh--not pink. I happened to have pink grapefruit in the house, courtesy of a food co-op of sorts called SHARE. Now I have a really neat use for them.

For my first batch, I ran out of Splenda and used half that and half actual sugar...probably closer to most of the SodaStream non-diet syrups.


1 Person Made This Project!


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9 years ago on Introduction

Is it possible then to make a ginger/lime/tulsi flavor soda by just boiling the prior with some sugar then sodastreaming it?


Reply 9 years ago on Introduction

I'm not acquainted with tulsi (at least I wasn't, until I looked it up on teh internetz just now). I'd probably treat your flavoring as tea. Try this:

Bring a little water to a boil, add ginger, lime zest, and tulsi to the boiling water, stop boil, let this mixture steep as you would tea (the tulsi and ginger may take longer than tea to infuse the water--experiment).

In a separate pan, make your sugar/water syrup, adding the lime juice to the sugar syrup. Strain ginger/lime zest/tulsi mix into sugar syrup, mix, let cool.

Sodastream some water, add a small amount of the mix to a glass, add seltzer to glass. See elsewhere for ChuCraft's Instructable on SodaStream mixes, and how she uses an old SS bottle for measuring out:


9 years ago on Introduction

That's a good idea as well, ancienthart. I thought I would experiment first, with existing fruits and such in the pantry (hence the use of grapefruit), before looking at cordial concentrates. I'll look into fruit cordial recipes. Thanks!


9 years ago on Introduction

My wife and I make plain soda water with our SodaStream, and pour it over concentrate cordials from the shop. In Australia we have a couple of very nice ones made by Bunderberg Ginger.
Maybe an easier route for you would be to make some home-made fruit cordials instead of soda syrups?