Choosing the right mud crab for cooking is important. I used to buy mud crab (aka. Scylla Serrata) in wet market near my house. Over the years, i have learned some tricks on how to choose fresh and meaty crab.
Delicious crabs are fresh crabs cooking with the right sauce. Here i list out ways to choose the meaty crab based on my experience.
Check its eyes and body movement
Fresh crab are crab still alive and looks aggressive when you get hold of it. The legs of the crab should be moving, the body is solid and firm.
Another way is crab eyes, make sure they are intact and still moving. This is because the eyes for mud crab is like a pulse for humans. Usually, mosquito like to bite the crab eyes or it was bump into some object during packing or sorting. If the eyes are not moving or look inactive, that mean the crab is weak and may die very soon.
Another way to check the freshness of the meaty crab is by pressing the crab elbow. If you press the elbow, it will swell again; it mean inside is solid and meaty.
When choosing meaty crabs, ignore the tendency to choose bright, shiny crabs. Instead, choose crabs with shells that are dull and scratched. You see, the dull and scratched shell shows the crabs are ready to replace the skin (molting to become soft shell crab) and have dense meat. Normally the crab will feed themselves a lot before molting – Crabs (and other crustaceans) cannot grow in a linear fashion like most animals. Because they have a hard outer shell (the exoskeleton) that does not grow, they must shed their shells, a process called molting. Just as we outgrow our clothing, crabs outgrow their shells. Prior to molting, a crab reabsorbs some of the calcium carbonate from the old exoskeleton, then secretes enzymes to separate the old shell from the underlying skin (or epidermis). Then, the epidermis secretes a new, soft, paper-like shell beneath the old one. This process can take several weeks.