Plunging a lobster (or crab) headlong into a pot of boiling water is not one of the best options because it is not exactly a humane method. Witnessing the doomed lobster's one or two second long spasm should prove this point to any doubting Thomas. The shock of this convulsive death does more than inflict pain on the lobster. It toughens its muscles and therefore your meal.
A more compassionate alternative to the plunging method is to sever the lobster's spinal cord before putting the lobster in the boiling water. This deadens its sense of pain. To sever the spinal cord, place the lobster right side up on a flat surface. Then, trust the tip of a knife downward into the natural breach where the head and front abdomen shells converge.
If you want to sever the spinal cord but are apprehensive about the thought of scuffling with an energetic lobster, you can use a method by placing the live lobster in a dish washing tub in a sink. Turn on both the hot and cold taps (be sure overflow water can pass through the sink's drain). When the tub is filled, turn off the cold water while increasing the flow of hot water until the water in the tub is very hot. Soon you'll see the lobster "go into sleep mode". Lift it out (it will be insensate and unaware of your presence). Now is the time to perform your culinary surgery before you boil the lobster. This hot tap water method can also be used to tame feisty live crabs.
Some cooks submerge the lobster (or crab) in a container of beer or wine. The crustacean becomes inebriated, relaxes its muscles, and reacts less spasmodically when dumped live into the seething cauldron of water. This method has validity, but today's wine and beer prices place it beyond the budget of most people. A lobster costs enough as it is.
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