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Asked by: Martin Egan, Ireland
Lobsters and other shellfish have harmful bacteria naturally present in their flesh. Once the lobster is dead, these bacteria can rapidly multiply and release toxins that may not be destroyed by cooking. You therefore minimise the chance of food poisoning by cooking the lobster alive.
That's great for us but what about the lobster? It has been argued that lobsters do not possess a true brain and so can't feel pain. It is fair to say that they are not self-aware in the same way that we are, but they do react to tissue damage both physically and hormonally, so they are obviously capable of detecting pain on some level. In fact, the hormone that they release into the bloodstream, cortisol, is the same one that humans produce when hurt. But the most visible sign of distress is the twitching tail, which evolved as an escape reflex.
Researchers at the University of Maine found that putting the lobster on ice for 15 minutes before dropping it into boiling water produced the shortest tail-twitching interval (20 seconds). Contrary to the popular urban myth though, placing the lobster in cold water that is then slowly brought to the boil does not anaesthetise the animal and appears to extend its suffering.
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