Who doesn’t want to eat tea bubbles?! And I’m not talking about tapioca pearls, fruit jellies, or popping boba that are commonly added to bubble tea.
Agar Fruit Tea Bubbles
Lisa (owner of TeaHaus, Ann Arbor) and her sons are always cooking up new things with tea, and they recently made bubbles, or pearls—not for tea, but using tea.
Passionfruit is a naturally caffeine-free blend (apple pieces, white hibiscus blossoms, freeze-dried passionfruit, mango bits, safflower, marigold flower, cornflower blossoms, and natural flavor) that makes a saturated-yellow cup (read more about passionfruit).
Summer Romance is a naturally caffeine-free blend (apple pieces, rose hips, hibiscus blossoms, elderberries, freeze-dried strawberry and raspberry pieces, strawberry leaves, vanilla pieces, and natural flavor) that brews into a gorgeous crimson color.
So to make your own tea bubbles, first brew a cup of strong tea (Lisa recommends fruit or rooibos blends). Strain the tea and then combine 1 cup of tea with 1 teaspoon agar. Bring to a boil while stirring with a whisk.
Then, using a dropper or syringe, drop the tea-agar liquid into very cold vegetable oil (freeze for half an hour before using).
Strain the bubbles out and rinse with water.
The tea bubbles are beautiful—and yummy!
Gelatin Black Tea Bubbles
It’s also possible to make tea bubbles with gelatin rather than agar, as both are gelling agents.
Gelatin is made of collagen, the protein that comprises a third of our body’s protein makeup. When gelatin is heated, its proteins come apart as long strands, and as the gelatin cools, the proteins start interweaving with each other. But when the gelatin is surrounded by cold oil, the proteins won’t interact with the gelatin so the strands form a sphere, which minimizes their contact with the oil. As they do this, liquid becomes trapped in the sphere and gels.
Agar comes from agarose, a polysaccharide (a carbohydrate made of sugar molecules) found in the cell walls of algae, a simple plant without stems, roots, or leaves. This vegetarian and vegan option for animal-based gelatin, as shown above, reacts like gelatin when dropped in oil, forming a sphere.
I tried my hand at using gelatin, choosing a flavored black tea. Wanting something with some heft, I chose the TeaHaus blend of Chili Chocolate, which contains tea (black, roasted green, and oolong), cocoa pieces, hazelnut brittle, blossoms, and spices. I love this tea because it’s a robust tea that has a hint of chocolate, but later, after you swallow, you get an incredible heat from the chili peppers that is positively addicting.
I brewed the tea a tad stronger than I normally would, and, over heat, added gelatin powder (one 7-g package to ¼ cup of tea), stirring until fully dissolved. After cooling for 5 minutes, I used first an eyedropper, and then a baster (with better results), to drop the warm tea solution into the cold oil.
As I had hoped, the bubbles had a tea-and-slight-chocolate flavor, but at the end I really got that heat of the chili peppers. For fun I tried them with a dollop of whipped cream (because why not?!) and considered what other foods—both sweet and savory—would pair well with these bubbles. Of course you could simply put these into iced tea, but why restrict them to tea?
And think about all the tea possibilities. Lisa’s flavorful fruit bubbles would be pretty on any summer dessert; Earl Grey bubbles might be lovely garnishing whipped cream and a delicate cake. What about sencha bubbles with sour cream atop a baked potato?
Molecular Gastronomy Fun!
No matter how you make or serve tea bubbles, you are engaging in molecular gastronomy, or the science of cooking, which investigates how the outcome is affected or determined by how the food is prepared. This still evolving field can also be defined as “the use of advanced chemical and biochemistry to create novel foods” (Sivakumaran 2018).
Transforming liquid tea into a gelatinous bubble is an example of spherification, one branch of molecular gastronomy, and a technique that is both widely used and highly researched. The chef controls not only the flavor, but also whether the spheres encapsulate liquid or a gel. To get a sense of the complexity involved, the chef must optimize such things as viscosity, acidity, calcium level, density, and concentration.
In addition to spherification, there’s also reverse spherification and even extrusion-based layer-wise deposition used with reverse spherification (basically a 3-D printer for making juice-filled bubbles). Although a basic knowledge of science has always been useful in the kitchen, today’s chefs benefit from extensive research conducted in laboratories and perfected in experimental kitchens. And of course there are chefs who are scientists themselves, inventing and innovating in restaurant kitchens.
But for the home cook, basic tea bubbles are fun and easy to make, yielding delicious results—and perhaps a novelty to serve at your next dinner party!
Source: K. Sivakumaran, “An overview of the applications molecular gastronomy in food industry,” International Journal of Food Science and Nutrition 3(3):35–40. May 2018.
Photos of agar tea bubbles courtesy of Lisa McDonald.