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For the caviar, you’ll use the same agar-

fruit mix, but you’ll use oil to turn food into

jelly globes called pearls. To do so in your

kitchen, grab a jar of quite cold canola or

light olive oil from the fridge.

Remove the lid. Using the eyedropper,

slurp up some of the juice-agar solution and

then drop it slowly into the oil. Watch the

solution freeze into little globules as it sinks.

Keep letting drops fall from the

eyedropper until the bottom of the jar is

covered in the tiny spheres. Transfer them to

a fine-mesh sieve and rinse with warm (not

hot!) water. Use your fruit caviar as a mad

scientist–style garnish on your next dessert.

What’s with all this agar stuff? It’s

a gelling agent found in dried seaweed

(it’s different from gelatin, which is made from

animal byproducts). Agar has five times the setting

power of gelatin, so you don’t need a lot to create

shapes that last. Agar melts at 185°F (85°C), but solidifies

at 104°F (40°C)—a phenomenon known as hysteresis. This

means that, once you have your solid agar blobs, you can

rinse them in warm water without melting them away. The

firmness of the gelled agar is affected by the acidity and sugar

content of the liquid with which you mix it. An acidic liquid

produces a more weakly gelled product, while adding sugar

can create a stronger gel.

What’s the Deal?