Strawberry Spheres with Ground Pepper
A simple spherification recipe to make strawberry spheres that explode in the mouth! Great for kids and very versatile. In this recipe we just serve them with ground pepper but the strawberry spheres can be used as a filling in a sponge cake, as a surprise inside some chocolate air or as garnish for many desserts such as chocolate mousse. Be creative and share with us your ideas in the comment section!
Ingredients for Strawberry Spheres
- 250g (8.8 oz) strawberry puree (~300g / 10.6 oz strawberries)
- 10g (0.35 oz) sugar
- salt pinch
- 5g calcium lactate gluconate (2%)
- Strawberry juice to store the spheres if you are not planning to consume them within a few hours.
- Coarse ground black pepper
- 1000 g (35 oz) distilled water
- 5 g sodium alginate (0.5%)
1- Using an immersion blender, puree the strawberries.
2- Pass the strawberry puree through a fine sieve.
3- Add the sugar, salt and calcium lactate gluconate. Blend.
4- Cover in plastic wrap and store it in the fridge overnight to remove the air bubbles.
Dispersing and Hydrating Sodium Alginate
1- Mix the sodium alginate with the distilled water using a blender until the sodium alginate is completely dissolved. If this is your first time doing this, be aware that it may take longer than expected.
Removing Air Bubbles
2- Strain the mix and store it in the fridge covered in plastic wrap overnight to eliminate the air bubbles.
Creating Spheres with Reverse Spherification
1- Get the strawberry puree with calcium content from the fridge, the sodium alginate bath and the 1Tbsp measuring spoon to make large spheres.
2- Prepare another bowl with plain water that you are going to use later for rinsing the spheres to remove the excess of sodium alginate.
3- Grab the measuring spoon; fill it with the strawberry puree and carefully pour it into the sodium alginate bath. Wipe the bottom with a paper towel, place the spoon over the bath slightly touching its surface and flip it to pour the liquid into the sodium alginate bath.
4- Stir the bath gently with the slotted spoon without touching the spheres. If you let them sit in the bottom of the bath, they will flatten and if you let them float, the top won't be covered with the sodium alginate solution and won't gel. Make sure the spheres don’t touch each other or they will stick. Start with one sphere at a time until you get used to the process. A flat bottomed pan may be better than a bowl if you are planning to make multiple spheres at a time.
5- Wait for about 2 minutes. The longer you wait the thicker the gel that will form. In general, for a good eating experience, you want the gel layer surrounding the sphere to be as thin as possible but it also needs to be strong enough to hold the shape and allow for careful handling. If the membrane is too fragile, they may easily break when you remove them from the bath or place them on the serving spoon.
6- Carefully remove the sphere from the sodium alginate bath using a slotted spoon and rinse it in the bowl with clean water.
TIPS: I recommend you always start with one sphere first to adjust the pouring process and the time in the sodium alginate bath. If the sphere membrane is too subtle and the sphere easily breaks when handling it with the slotted spoon carefully or when plating it, extend the time in the calcium bath until you get the desired strength. Keep in mind that the thinner the membrane the better experience people are going to have when eating it.
Storing the Spheres and Preserving the Flavor
One of the biggest benefits of Reverse Spherification is that you can store the spheres to be consumed later. If you leave the spheres in contact with air, the gel will start to dry and eventually break. You need to store them in a liquid bath. However, since the gel membrane around the sphere is permeable to small molecules, osmosis will occur if submerged in water and dilute the flavored liquid inside the sphere. To preserve the flavor, store them in a bath of the same flavored liquid in the fridge, strawberry juice in this case.
Assemble and Serve
1- Place the strawberry spheres on appetizer spoons.
2- Garnish with coarse ground black pepper.