Edible Fluorescent Mineral Tutorial

Our January/February issue is out NOW and it’s an incredible showcase of Agate. Geode and Gemstone cakes. Adela Calvo of Delicut Cakes shares a wonderful step-by-step tutorial for glowing, Fluorescent minerals. Adela notes, “Fluorescent minerals are amazing. I wanted to make a totally food-safe version of these minerals, that can be used on cakes to really bring the wow factor.  After experimenting with many different kinds of products and researching the easiest way to create these crystals I came up with these techniques.”
Ingredients and tools
1 sachet of powdered gelatin
1 Indian tonic water
1 little bowl
1 teaspoon
Mix three teaspoons of gelatin with the same proportion of tonic water, then heat the mixture in the microwave for 20 seconds or until the powdered gelatin has dissolved completely.
Then pour it into the desired mold. If foam
appears, remove it with a spoon and let it set overnight.
After setting overnight remove it from its mold. The texture should be dry but flexible TIP: If it
is too hard you won ́t be able to cut as you want to, so you would have to heat again and pour
another teaspoon of tonic water into the mixture.
For this step, we can use an Exacto cutter or scissors to cut sharp edges all around the gelatin so it looks like a transparent gem. We can also use the remains to decorate as they the look like small crystals.
Now with an ultraviolet light, you can see how the gelatin crystal glows. To stick the crystals on the cake you will need to spray glaze on the fondant and let it dry, otherwise, the gelatin will dissolve the fondant making it slimy and gooey.
In my creation, I carved a hole in the cake, I covered the back of the hole with a thin layer of fondant so we don ́t see the cake and afterward I glazed it. When dry, I inserted the gem in the hole which stuck to the glaze.
Ingredients and tools
tbsp Indian Tonic water
1 vitamin C tablets
silicon mat
protective gloves
Put 6 tablespoons of isomalt with 2 tablespoons of Indian tonic water into a saucepan and melt. Remove from the stove when totally melted. Once the bubbles have disappeared pour the mixture onto a silicone mat and leave to cool down. This mixture will remain mold-able even after it has cooled down thanks to the proportions of tonic water. In ultraviolet light, the whitish crystals will look blue.


WARNING: use protective gloves to protect your hands from burns as the mixture is very hot.

TIP: If you want the isomalt crystal to be hard and have an orange/yellow color, all you do is mix 6 tablespoons of isomalt to 1 tablespoon tonic water to which you have added an effervescent vitamin C tablet. Melt as before and pour onto the silicon mat, the isomalt will harden and you can then crack it to resemble the yellow fluorite mineral. In ultraviolet light the
yellowy crystals will look greenish.
In these pictures, you can see the isomalt crystals placed on the fondant that had been previously marked. You can also see the flexible strings of isomalt molded into the furrows on the fondant and lastly, you can compare the hues in a different kind of lighting.
Ingredients and tools
White chocolate (without whitening)
Powdered pigments
White chocolate is in itself fluorescent so all you need to do is to melt it in the microwave, in fact, you have to overheat it slightly so it does become thick and lumpy
but does not burn. Make 2 balls of chocolate, 1 ball twice the size of the second. It is then that you can add the powdered pigments by kneading the chosen color using the smaller of the 2 balls of chocolate. Then roll and twist both balls together to make a marbling effect.
If you want to paint with the chocolate, melt it till it is runny, but this time do not overheat it.
TIP: There are some makes of chocolate that need cocoa butter added to
make it runny. Add the chosen pigment, mix well and paint.
Indian tonic water mixed with gelatin in ultraviolet light: You could actually write a secret message with it on the cake as long as it is liquid and runny, just write your message, then let it dry. When you shine ultraviolet light on the cake the message will be revealed!

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