The picture above shows what appear to be three very different things but, in fact, they are just different forms of a product used in Chinese and South-East Asian cookery, and commonly referred to as ‘Fish Maw’. The word maw actually means stomach, or gullet, and, as such, the term for this product is a bit of a misnomer as it is really the ‘Swim bladder’ of certain bony (non-cartilaginous) species of fish. The swim bladder, is a gas filled sac that lies in the belly and allows the fish that possess them to maintain and control buoyancy at different depths.
As with a number of products in Chinese cookery, this item is used primarily for its texture. Some sources state bluntly that it has no taste of its own but, like tofu, takes on the flavors of other ingredients in a dish. In fact, it does have a certain, mild, ‘fishiness’, but it is still the texture that is important. It is rich in collagen, which not only gives a pleasant texture itself, but the collagen will dissolve into soups and braising liquids to lend added richness.
Several species are harvested for their bladders (Yellow Croaker is a favored type), but I do not know what from what fish any of the ones you see picture were taken… the packages I have, all written exclusively in Chinese characters, are silent on that point… In any event, the two basic forms are the plain dried article (the yellowish things at the bottom right of the picture), and the sort that consists of the same thing that has been deep-fried before being packaged for sale…
Here you can see a close-up the plain dried article. They have a slightly translucent appearance, and a rather plastic feel. I have read that some unscrupulous dealers pass off squid ‘tubes’ as dried fish maw, however, being quite familiar with those, I am confident that is not the case here. The aroma of the plain dried sort is, however, a little like dried squid (albeit a bit milder).
Here are two types of the deep-fried variety. They have a spongy look, although they are quite firm, and even brittle, and the smaller pieces remind me very much of fried pork-rinds. Again, there is some deception practised in the industry with fried shark-skin often being substituted for the real deal. I am almost certain, though, that this not the case with the small curled pieces you see pictured, but I am less confident as regards the large flat sheet variety. The deep-fried maws don’t have much aroma that I can detect but there is a fishy quality to the taste (no pun intended) that I found much stronger in the ‘sheet’ type … so… who knows?
Both sorts of fish maw need to be reconstituted before using in a dish. The plain dried sort is typically first soaked in water to soften, for a fairly extended period, and then simmered to soften even further.
The initial soaking time will depend upon the age and thickness of the pieces, and 6 – 12 hours is often cited. However, you have a lot of lee-way and can leave it soaking for quite a long time without any problems and it is a simple matter to start soaking on one day then leave it overnight in the fridge for use the following day.
The simmering part can be omitted if you are using the maw for soups or slow-braise dishes, but simmering, with a bit of ginger added, is often employed in Chinese cookery to remove any ‘fishy’ taste. Personally, I don’t regard this as an issue (and I don’t bother to change the soaking water several times as is often suggested), but, if you do undertake this step, know that you have less lee-way than with the cold soaking. Some say to put the maw in water, bring it to the boil and the remove from the heat and leave it to sit until cool. However, I found that putting it onto water already at a low simmer and leaving it, still simmering, for an hour, or so, works nicely. Much longer, and you will make It too soft and leech out a good deal of the collagen that will add richness to your finished dish.
Here is the plain dried sort after both operations. You can see that it is both limp and soft at this point. If you try tasting it at this stage, you will already be able to see why the foodstuff is prized for its gelatinous, collagen-rich texture.
If you don’t want to go through the fairly lengthy soaking process if all you have is the plain dried sort rather than commercially deep-fried, you can always deep-fry it yourself. Just drop pieces in moderately hot oil and fry for a minute or two until they puff up… Once done, you then can proceed to the much simpler soaking process as follows….
The deep-fried variety of fish maw needs a very short time in water to be reconstituted for use. As little as fifteen minutes, up to thirty or so is all that is necessary, depending on thickness and density. Here you can see how the soaked deep-fry type becomes just as soft and flexible…
Fish maw is primarily used in soups and braised dishes, but can also be stir-fried. There are no hard-and fast rules, by any means, but the plain dried sort is particularly suited to soups and braised dishes, especially those that are cooked long and slow. The deep-fried sort can also be use here (although you probably would use shorter cooking times once the maw is added to your preparation), but it is a much better choice, in my opinion, for stir-fried dishes.
Here is a soup I made using some of the soaked and simmered plain-dried sort. Fish maw with crab meat is quite common, but here I used shredded lobster flesh (as I had some left from a can of frozen lobster meat). I used the ‘liquor’ from the can along with a little chicken stock for the base and added nothing else except the fish maw and some frozen peas. No seasonings were necessary and a somewhat slow cooking of the maw in the broth before adding the lobster and peas gave the finished result a lovely unctuous richness.
Stay tuned… some actual detailed recipes using fish maw will follow shortly….