So when I went to lunch with friends at TenPenh restaurant last week, the "tempura ponzu softshell" winked at me from the menu. Everyone's always raving about how good soft-shell crabs are, but I've always been a tad skeptical that an exoskeleton could really be edible, let alone tasty.
I tried to ignore it and order salmon, which I know I like, but then I asked the waiter where it came from. Farmed, and he didn't know how or where. Uh oh. Not wanting to risk supporting unsustainable aquaculture practices (see this fact sheet on farmed salmon for an explanation), I pointed to the crab instead.
It arrived whole, the shape of its claws still clear beneath the batter, and appeared to be scuttling toward me—though it was merely sliding a bit on its bed of cucumbers and rice as the waiter set my plate down. I picked up my fork and knife more out of defensive reflex than actual appetite.
I tasted a mixture of salt and buttery sweetness, as well as that flavor that can only be described as "oceany." A few globs of something light green, like wasabi paste, oozed out as I cut closer to the crab's head.
"What's this?" I asked my friend.
"Just eat it," she said. "It's like a delicious mustard, and that's all you need to know."
Actually, it was probably the crab's liver and pancreas, often called mustard or tomalley. I pushed it aside, preferring the taste of the sweet chili dipping sauce. Other than that, I ate every last bite on my plate.
I was surprised at how easily I could cut through the shell, it was no tougher than chicken skin. That's because the creature had just shed its hard shell to grow a larger one, as blue crabs do some 18 to 23 times within their three-year life spans, according to the Maryland Seafood & Aquaculture Program.
If a crab is removed from the water right after molting, its new shell does not have a chance to harden—something fishermen figured out more than 100 years ago.
"A dainty succulent soft shell crab, nicely cooked and well browned, tempts the eye of the epicure and makes his mouth water," one writer enthused in a New York literary journal in 1870. His explanation of the molting process is more poetic than scientific, but I like it:
"Making a great effort to throw off the incubus of babyhood that weighs so heavily upon them, they burst open the back door of their shell and crawl out...they gaze in stupefaction at their old shell, amazed to find out that they have, by their own efforts, unaided and alone, accomplished such a wonderful change. The thought is overwhelming. It fills them with pride; rejoicingly they exult, and swell with gratification... they have increased their bulk to nearly double its former size. They can't get back into the old shell now, for it won't fit them...The only thing left for them to do is build another house.What's your favorite way—or favorite place—to eat soft-shell crabs?
It takes three or four days before they get fairly to work, and during that time they are called soft-shell crabs. This stage is particularly dangerous to the delicate creatures...Tender, helpless, innocent and beautiful, they are almost certain to be victimized and gormandized."