Tube and flat fish maw are the same ingredient in two different shapes. Both are the dried swim bladder of a fish. Tube maw keeps the bladder's natural hollow, cylindrical form, while flat maw is the same bladder split open and pressed into a sheet. That single difference shapes how each one soaks, how it looks on the plate, and which dishes it flatters most.
Key takeaways
- Fish maw (bong bong ca, 花胶) is the dried swim bladder of a fish, a long-standing banquet ingredient in Chinese and Vietnamese kitchens.
- Tube maw holds its round, hollow shape and gives soups a springy, gelatinous bite.
- Flat maw is opened and pressed into a smooth sheet that suits braises and sliced platters.
- Both soak overnight until soft, then take on the flavor of the broth or sauce around them.
- Choose by the dish you are making and the look you want, not by which shape is “better.”
What fish maw is
Fish maw — bong bong ca in Vietnamese, 花胶 in Chinese — is the swim bladder of a fish, cleaned and dried until it becomes a firm, amber-to-pale-gold piece. In its dried state it is light and brittle, with a ridged, honeycomb-like surface. Once soaked and cooked it turns soft, translucent, and gelatinous, and it readily takes on the flavor of the soup or sauce it sits in. It has been a fixture of banquet cooking for generations, valued for its texture and for the body it lends a rich broth.
Tube fish maw
Tube maw is dried in the bladder's original form, so it looks like a hollow, curved tube or cone with a ridged surface. Because it keeps that open structure, it puffs and springs back when soaked, giving a bouncy, gelatinous bite. The hollow center traps liquid, which is why tube maw is a classic choice for soups and double-boiled dishes where you want it to drink up the broth. Our Fish Maw – Tube comes in a 213 g (7.5 oz) pack.
Flat fish maw
Flat maw is the same bladder split open and pressed flat into a sheet, so it lies smooth and even. It tends to have a denser, more uniform texture and holds its shape well over longer cooking, which makes it a natural fit for braises and for slicing onto a platter. Our Fish Maw – Flat is also 213 g (7.5 oz).
Which shape for which dish?
Soups and double-boiled dishes
For clear soups and double-boiled dishes, tube maw is the traditional pick. Its hollow form soaks up stock and gives each spoonful a light, springy piece that carries the flavor of the broth.
Braises and platters
For a slow braise or a dish where the maw is sliced and arranged on a plate, flat maw is easier to handle. Its even sheet cuts cleanly and stays intact through longer cooking, taking on a glossy coat of sauce.
How to choose
Neither shape is better — choose by the dish and the presentation you want. Reach for tube maw when you want a bouncy piece in a soup, and flat maw when you want tidy slices in a braise. Both start the same way: soak overnight until soft, blanch briefly in water with ginger and scallion to remove any odor, rinse, then cook. You will find both in our Seafood collection.
Frequently asked questions
Is tube or flat fish maw better?
Neither is better. They are the same ingredient in two shapes. Tube maw suits soups; flat maw suits braises and sliced platters.
How do you prepare dried fish maw?
Soak it overnight until soft, then blanch it briefly in water with ginger and scallion to remove any odor. Squeeze and rinse it, then add it to your soup or braise.
What does cooked fish maw taste like?
On its own it is mild. Its appeal is the soft, gelatinous texture and the way it absorbs the flavor of the broth or sauce it is cooked in.
