A lobster burger is seen in this handout photo.

If making a meal featuring crab or lobster involves dropping it in a pot of boiling water, be aware that tasty crustacean will be hurting.

The subject of whether crustaceans feel pain has been debated for years.

Professor Robert Elwood of Belfast's Queen's University collected 90 crabs from a nearby beach and placed them in a large tank containing two similar shelters.

One shelter dispensed a small electric shock when a crab entered.

Elwood would remove the crabs from the tank for a short time and then return them to see if they chose a different shelter. The second time in the tank, the crabs returned to the shelter they first chose.

On the third trip to the tank, the shocked crabs would seek an alternate shelter to avoid receiving another shock, which is consistent with the definition of pain in other species, the study says.

The study was published in the Journal of Experimental Biology.