How starch superpowers your bubble tea
Bubble tea was invented in Taiwan in the mid-1980s. Exactly who invented it is not clear, since two tea houses have vociferously laid claim to it: Chun Shui Tang in Taichung City and Hanlin Tea Room in Tainan City, about 150 km away.
The rivalry between them grew so intense that they ended up in court, in what would be a decade-long battle. In 2019, the court ruled, rather anti-climactically, that the question of invention was irrelevant, since bubble tea is not a patented product. Well, so much for ownership.
Now to more flavourful matters. Boba is made by adding chewy tapioca pearls to different kinds of tea. And while boba is what this beverage is called around the world, that term is considered rather rude in its birthplace, since the word is Taiwanese slang for breasts.
The term “pearl milk tea” (zhen zhu nai cha) is used instead. The pearls elevate the tea, by giving it khiu.
In Hokkien (which is a form of Min Chinese spoken in Taiwan), “khiu”, now shortened and modernised as “Q”, is an idealised chewy texture, characterised by springiness and bounce, that occurs in certain foods: some noodles, mushrooms, fish cakes, and boiled tapioca pearls too. This texture is considered so desirable in Taiwanese cuisine, that parallels are often drawn with the umami flavour in Japanese food. Walk through the streets of Taiwan and one will see a large letter Q on food stalls, to indicate that dishes they offer bear this characteristic. There’s a solid reason tapioca has khiu. Every starch has a superpower. Corn starch, for instance, crisps remarkably well when fried, and so it is used as a batter. Mung bean starch stays stable even at high temperatures, so it is used to make gluten-free noodles.
Tapioca is interesting. Raw, the root vegetable — cassava — is poisonous to humans, mixing with saliva to form hydrogen cyanide. But shred it and boil it, and the toxic compounds are eliminated. Grind it into a flour and boil it, and the isolated starch is sticky and elastic, perfect for little tapioca balls or pearls.
These starches are largely short-chain amylopectins. When boiled, they yield a structure so dense that it isn’t altered when immersed in a hot or cold drink. (The spheres are also delicious when sauteed or fried, as anyone who has eaten a sabudana khichdi; above, papad or vada will know.)
This starch behaves impeccably in low temperatures too. It doesn’t harden when refrigerated (as rice does, in the process called retrogradation).
Tapioca pearls can be frozen and thawed with very little damage to their structure. Their neutral flavour and clear, glossy appearance make them amenable to a range of sweet and savoury dishes. (Since the starch comes from a tuber and not from a glutinous grain, it is also naturally gluten-free.)
Bubble tea was originally a scoop of the pearls in sweet, iced milk tea; then the green, oolong and jasmine variants were added to menus. Today the pearls are used in fruit-based beverages too.
My younger daughter loves bubble tea; it’s a day-long treat for her. She will buy it and sip on it languidly, taking her time to chew each pearl. This, I think, is a key attraction — the sense of satisfaction and satiation that the drink affords, through the filling starch, the chewing, and the coveted texture.
I must admit that I am not a big fan. I prefer to sip rather than chew my caffeine fix. Nonetheless, this segment is worth an estimated $2.6 billion globally.
I hate to poke at a bubble, but I do feel compelled to mention that a cup of tapioca pearls contains 545 calories (about as much as a large cheeseburger). And that’s without the sugar, juice and other ingredients in the glass.
Don’t strike it off the list; just, as with all calorie-rich foods, keep the heft in mind? It’s hard for a body to burn that off, unless you’re sipping on your way to the gym.