Whether entertaining friends or snacking after school, it’s fun to sip on a sweet beverage, and you can use science to help you create the perfect thirst-quencher.

BY ADDING LOTS OF SUGAR TO WATER AND HEATING THE MIXTURE, YOU CAN CREATE A SIMPLE SYRUP, WHICH SCIENTIST CALL A “SUPERSATURATED SOLUTION”. THESE TASTY SYRUPS CAN BE USED TO SWEETEN AND FLAVOR EVERYTHING FROM TAPIOCA TO CARBONATED WATER.

If you prefer to carbonate your own soda, a microorganism called yeast can help you out. Yeast produce carbon dioxide when they eat sugar, so by mixing water, sugar, yeast and flavoring, you can bottle your own bubbles.

Other tasty beverages in this course include bubble tea, made by rehydrating tapioca pearls, and colorful lemonade density gradients.

COOK UP FLAVORFUL FRUIT SYRUPS THAT TRANSFORM CARBONATED WATER INTO HOMEMADE SODA POP. IT’S FUN TO EXPERIMENT WITH DIFFERENT COLORS AND FLAVORS.

  Medium or large saucepan with a heavy bottom

  Strainer or colander

  Spoon

  Stove

RECIPE

1. Add the fruit, water, and sugar to the saucepan. (Fig. 1, 2)

Fig. 1: Measure the berries and add them to the saucepan.

Fig. 2: Pour in the water and sugar.

2. Bring the mixture to a boil over medium-high heat.

3. Stir and boil for about 15–20 minutes, until the fruit is soft enough to crush with a spoon as you cook it. Some kinds of fruit will take longer than others. (Fig. 3)

Fig. 3: Cook until the fruit is soft.

4. Let the mixture cool.

5. Place a colander or strainer over a bowl large enough to hold the contents of the pan. Use a spoon to push the liquid through, collecting it in the bowl underneath. (Fig. 4)

Fig. 4: Strain out berries.

6. Add a few tablespoons of the syrup to a glass of carbonated water and stir to make fruit soda. (Fig. 5)

Fig. 5: Stir the syrup into carbonated water.

7. Sip your homemade soda. (Fig. 6)

Fig. 6: Sip your homemade soda.

THERE’S NOTHING BETTER THAN AN ICE-COLD MUG OF ROOT BEER, AND IT’S FUN TO BREW YOUR OWN FLAVORFUL BLEND USING YEAST, SUGAR, WATER, AND A SODA BASE. ONCE YOU MASTER ROOT BEER, YOU’LL BE READY TO TACKLE ANY SODA FLAVOR.

  2 cups (400 g) sugar

  1 tablespoon (15 ml) root beer or soda pop extract (base)

  1/8 heaping teaspoon yeast (champagne, wine, or beer yeast works best, but fresh baker’s yeast may be used)

  Clean, empty plastic soda bottles with caps

  Labels and pen

  Large stirring spoon

  Small bowl

  Funnel (optional)

Follow the instructions in the recipe, continuing to check the bottles periodically once you’ve moved them to a cooler spot and chilling them in the refrigerator before you open them.

There may be some yeast residue at the bottom of the bottles. It’s safe to drink, but pouring carefully will keep it from clouding up your beverage.

Fig. 1: Add yeast to warm water.

2. Pour 2 cups sugar into a one gallon (4.5 L) container and add enough water to bring the volume to 8 cups. (Fig. 2)

Fig. 2: Add sugar and soda extract.

3. Shake up the root beer extract and add 1 tablespoon to the sugar/water mix. Stir well.

4. Add 7 cups of water and the yeast mixture from Step 1 to the sugar-water mixture to bring the volume to 1 gallon. Mix well.

5. Fill clean, plastic bottles with the root beer mixture to within 1–2 inches (2.5–5 cm) of the top and screw the caps on tightly. (Fig. 3)

Fig. 3: Fill bottles with mixture..

6. Add dates and labels to the bottles. (Fig. 4)

Fig. 4: Add labels and dates.

7. Squeeze the bottles to check how firm they are before fermentation begins.

8. Let the root beer sit at room temperature for 3–5 days, feeling the bottles occasionally to see whether they’ve become firmer from carbon dioxide gas pressure.

9. When the bottles feel firm, lay them on their side on a baking sheet and store them in a cool, dark place for 1–2 weeks. Then, put them in the refrigerator upright for 1–2 days before opening.

10. Taste your homemade root beer and share it with friends. (Fig. 5)

Fig. 5: When the bottles feel firm, chill them to enjoy the root beer with friends.

BUBBLE TEA IS A WELL-KNOWN DRINK THAT HAS BEEN POPULAR FOR YEARS. MAKE YOUR OWN VERSION OF THIS DELICIOUS DRINK BY COOKING UP SOME BOBA TO ADD TO YOUR FAVORITE TEA OR SMOOTHIE.

  2 cups (475 ml) water

  1/4 cup (56 g) boba tapioca pearls

SIMPLE SYRUP

  2 cups (300 g) brown sugar

  1 cup (235 ml) water

FRUIT SMOOTHIE BUBBLE TEA

  1 cup (255 g) frozen fruit

  1 cup (235 ml) milk

  2 tablespoons sugar (26 g) or honey (40 g)

MATCHA BUBBLE TEA

  1 teaspoon matcha powder

  1 cup (235 ml) milk

  1 cup (140 g) ice

  2 tablespoons sugar (26 g) or honey (40 g)

  Blender

  Mixing spoon

  Stove

Adult supervision required for cooking sugar syrups.

Use metal or paper bubble tea straws, if you can find them, since they’re better for the environment.

2. Add the boba pearls and stir until the tapioca begins to float to the top.

3. Cook the boba over medium heat for 15 minutes, then turn heat off and let them sit for another 15 minutes to keep absorbing water. While the boba sit, make simple syrup (below).

4. Make a simple syrup to sweeten the boba pearls. Add 2 cups (300 g) brown sugar to 1 cup (235 ml) water in a medium saucepan.

5. Boil the mixture until the sugar dissolves. Remove from heat.

6. Rinse and drain the cooked boba. (Fig. 1)

Fig. 1: Cook the boba in water, then rinse and drain.

7. Add the boba to the simple syrup. They will keep in the refrigerator for at least a week. (Fig. 2)

Fig. 2: Add syrup to sweeten and store boba.

8. Blend together the ingredients for either the Fruit Smoothie Bubble Tea or the Matcha Bubble Tea in the ingredients list. (Fig. 3)

Fig. 3: Blend up a smoothie or some icy matcha tea.

9. Add some boba to the bottom of a clear glass and pour the bubble tea mixture over them. Taste the bubble tea. If it needs more sweetness, stir in a little bit of the simple syrup. (Fig. 4, Fig. 5)

Fig. 4: Add boba to a glass and pour smoothie or tea over boba.

Fig. 5: Make plenty for everyone!

LOADED WITH SUGAR MOLECULES, SIMPLE SYRUPS CREATE A DRINKABLE DENSITY GRADIENT, SITTING AT THE BOTTOM OF THE GLASS UNTIL YOU MIX THEM IN.

  Lemonade

  Carbonated water

  Raspberries (optional)

  Spoon or straw

Fig. 1: Pour fruit syrup into the bottom of a glass.

2. Use a spoon or a straw to slowly and carefully layer lemonade on top of the syrup. It works best it you let the liquid run down the side of the glass. (Fig. 2)

Fig. 2: Use a spoon to layer lemonade on top of the syrup.

3. Add just enough fruit syrup (a different color, if you have it) to some carbonated water to tint it a light color. Layer it on top of the lemonade. (Fig. 3)

Fig. 3: Add some syrup to carbonated water and layer it on the lemonade.

4. Float a piece of fruit on top, if you have it. (Fig. 4)

Fig. 4: Float a piece of fruit on top.

5. Taste your creation. (Fig. 5)

Fig. 5: Taste it!

6. What other fruit juices, syrups, and sodas could you try? (Fig. 6)

Fig. 6: What other syrups, juices, and sodas can you layer?