This is a fun kitchen science project that can add a huge wow factor to almost any dish you serve. Molecular gastronomy – sometimes called modernist cuisine – isn’t just for adults, however, as it is the kind of delicious science that kids of all ages seem to really enjoy. The littlest ones can watch and then play with – and eat – the results, although older children and teens can probably follow this recipe all by themselves. While kids (and even some adults) may not be familiar with the term “molecular gastronomy,” if you tell them they’re going to take a liquid and turn it into little jelly-like bubbles they can hold in their hand and then eat, you’re sure to capture their attention.
The science behind this neat trick is called spherification and it is commonly used in many restaurants today because it’s one of the easiest techniques in the molecular gastronomy toolbox. I’ve enjoyed finding little pearls or bubbles of beet juice, green tea, watermelon, sriracha, balsamic, grapefruit and more on restaurant plates over the past few years.
You only need a few simple ingredients and tools to conduct this experiment, outlined below. If you’re using water instead of juice, it might be fun to add a drop or two of food coloring so the experiment is more visually appealing. You can find the two necessary food-grade chemicals, both of which are naturally derived, online or at local molecular gastronomy supply shops. Sources in Canada include Powder for Texture and Nella Cucina; in the United States visit Modernist Pantry’s online shop, which also ships worldwide.
If you’re looking for other fun and extremely easy edible science experiments, check out this rock candy recipe and the instructions for making potato chips in the microwave.
Edible Juice Bubbles
Ingredients
- •118 ml (1/2 cup) pulp-free juice or tinted water
- •1.3 ml (1/4 teaspoon) sodium alginate (seaweed based)
- •5 ml (1 teaspoon) calcium lactate
Equipment needed:
- Small , medium and large bowls — approximate sizes: 473 ml (2 cup), 946 ml (4 cup), and 1420 ml (6 cup)
- 1.3 ml (1/4 teaspoon) and 2.5 ml (1/2 teaspoon) measuring spoons
- Immersion blender or electric beater
- Whisk
- Sieve (optional but useful)
- 5 ml (1 teaspoon) measuring spoon with a deep bowl or other small spoon
- Syringe (optional but useful)
- Slotted spoon
- Plate
Preparation
- Line the bowls up in order of size. Put the pulp-free juice or tinted water into the smallest bowl and add the sodium alginate to the liquid. Use an immersion blender or electric beater to completely dissolve the sodium alginate. Set the mixture aside to allow air bubbles to dissipate.
Add 473 ml (2 cups) of cold water to the medium bowl. Whisk in the calcium lactate. It may not completely dissolve but whisk for a few minutes to get the majority of it to dissolve.
Add 946 ml (4 cups) of cold water to the largest bowl and set the sieve over top so that most of the sieve is under water. The sieve is not essential but it can make it easier to scoop out the water or juice bubbles after they’ve been rinsed.
Using a 5 ml (1 teaspoon) measuring spoon with a deep bowl or another small spoon, scoop up a full spoonful of the first mixture (the juice or tinted water + sodium alginate) which should feel slightly gelled. Very carefully drop the gelled mixture into the second bowl (containing the cold water and calcium lactate mixture). It will take a little practice to get perfectly round spheres but the odd shapes taste the same and can be rather fun looking! If you want to make really tiny bubbles or pearls, to garnish a dish, using a syringe is the easiest way to accomplish this. Fill the syringe with the gelled mixture then dispense a drop at a time into the second bowl.
Repeat the above steps (scooping and dropping or suctioning and dispensing) until you have a number of juice bubbles in the middle bowl, but not too many as you want to avoid overcrowding as that may cause the bubbles to stick together. Using a finger or a small spoon, gently stir the liquid around the bubbles for three minutes, keeping the bubbles gently in motion.
Using the slotted spoon, carefully transfer the bubbles to the third bowl to stop the chemical reaction and rinse them off. Gently place the bubbles on a plate and repeat with the remaining sodium alginate + juice (or tinted water) mixture. Your bubbles will now be ready to carefully pick up, jiggle and, of course, pop into your mouth! They’ll feel a little slimy but will taste just fine.
