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Make a magical snack

Make a magical snack
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Make glowing jelly snacks using tonic water and gelatin. Prepare molds, chill until set, then reveal fluorescence under a black light with supervision.

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Step-by-step guide to make glowing jelly snacks

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3 Easy Snacks Kids Can Make | Recipe Compilations | Allrecipes.com

What you need
Adult supervision required, black light, heatproof measuring cup, refrigerator, saucepan, silicone molds or small cups, small bowl, spoon, sugar optional, tonic water, unflavored gelatin powder

Step 1

Gather all the materials from the list and bring them to your workspace.

Step 2

Wash your hands with soap and water.

Step 3

Measure 1 cup of tonic water into a heatproof measuring cup.

Step 4

Pour 1/4 cup of the tonic water into a small bowl and sprinkle 1 tablespoon of unflavored gelatin over the surface to bloom it for 1 minute.

Step 5

Heat the remaining 3/4 cup of tonic water in a saucepan over medium heat until it is hot but not boiling.

Step 6

Pour the hot tonic water into the bowl with the bloomed gelatin and stir until the gelatin is completely dissolved.

Step 7

Stir in 1 tablespoon of sugar if you want your snack sweeter and mix until the sugar dissolves.

Step 8

Carefully pour the jelly mixture into silicone molds or small cups.

Step 9

Let the filled molds cool on the counter for 10 minutes.

Step 10

Place the molds in the refrigerator and chill for at least 2 hours until fully set.

Step 11

Ask an adult to bring the set molds into a dark room and turn on the black light.

Step 12

Unmold one glowing snack and hold it under the black light to watch the fluorescence appear.

Step 13

With an adult’s permission taste a small bite to enjoy your glowing snack.

Step 14

Share your finished glowing snack on DIY.org.

Final steps

You're almost there! Complete all the steps, bring your creation to life, post it, and conquer the challenge!

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Help!?

What can I use instead of tonic water or unflavored gelatin?

You need quinine-containing tonic water for the glow so it can't be replaced, but for a vegetarian option you can swap the 1 tablespoon unflavored gelatin for about 1 teaspoon agar-agar and boil it with the 3/4 cup tonic water instead of blooming.

My jelly didn't set or didn't glow — what went wrong?

If it didn't set, you likely skipped blooming the 1 tablespoon gelatin for 1 minute or didn't fully dissolve it in the hot 3/4 cup tonic before pouring and chilling for at least 2 hours, and if it didn't glow make sure you used tonic water and viewed it under a black light in a dark room.

How can I adapt this activity for different ages?

For toddlers have an adult handle the hot saucepan and unmolding while the child sprinkles and pours the bloomed gelatin into silicone molds, and for older kids let them measure 1 cup tonic, bloom the 1 tablespoon gelatin, stir in sugar, pour, and refrigerate with supervision.

How can we enhance or personalize the glowing snack?

To personalize, use fun silicone mold shapes, stir in a pinch of clear edible glitter to the jelly mixture before pouring, or make layered glowing snacks by chilling the first layer until set and then pouring a second layer.

Watch videos on how to make glowing jelly snacks

Here at SafeTube, we're on a mission to create a safer and more delightful internet. 😊

3 Fun Summer Snacks Kids Can Make | Easy Snack Recipes for Kids by MOMables

4 Videos

Facts about kitchen science for kids

⚠️ Supervision matters: use food-safe molds, let hot liquids cool before kids handle them, and avoid shining UV lights into anyone's eyes.

💡 Black lights give off UVA (long-wave) ultraviolet that makes some molecules glow while the light itself looks faint to our eyes.

🐄 Gelatin comes from collagen (usually from animal bones and skin) and turns liquids into jiggly desserts when chilled.

🧪 Quinine in tonic water absorbs UV light and fluoresces bright blue—perfect for spooky glowing snacks!

🍸 The quinine levels in commercial tonic water are low and safe to eat in food, and it's also what gives tonic its characteristic bitter bite.

How do I make glowing jelly snacks with tonic water and gelatin?

To make glowing jelly snacks, sprinkle unflavored gelatin over a small amount of cold tonic water to bloom. Gently heat the rest of the tonic water until hot (not boiling), stir in the bloomed gelatin and optional sweetener or juice, then pour into food-safe molds. Refrigerate until fully set (usually 2–4 hours). Unmold and show the snacks under a black light for fluorescence. Always let hot liquids cool a bit and supervise children during the whole process.

What materials do I need to make glowing jelly snacks?

Materials: tonic water (contains quinine for the glow), unflavored gelatin or agar for a vegan option, measuring cups and spoons, saucepan, heatproof bowl, whisk, silicone or plastic food molds, sugar or natural sweetener if desired, refrigerator, and a safe UV black light to reveal fluorescence. Also have serving spoons, napkins, and adult supervision ready. Avoid using metal molds to prevent taste changes and choose clear molds for the best glow.

What ages are glowing jelly snacks suitable for?

Suitable ages: This activity is best for school-age children (about 6–12 years) who can help mix and pour with supervision. Younger preschoolers (3–5 years) can assist with safe, non-hot steps like choosing molds and decorating, but should not handle hot liquids. Not recommended for infants or toddlers who may choke on small molds or consume excessive tonic water. An adult should always oversee preparation, refrigeration, and serving.

Are glowing jelly snacks safe and are there variations or benefits?

Safety and variations: Quinine in tonic water is safe in small quantities but avoid giving large amounts to infants; if your child has health concerns or takes medication, consult a healthcare provider. Use a food-safe black light and don’t look directly into the UV lamp. To vary, try flavored gelatin mixes or swap some tonic water for clear fruit juice (may reduce glow). This activity boosts curiosity about science, sensory exploration, and fine motor skills when kids help with molds and decora
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