Each is born in a tough, white membrane or shell.

It is encased in a tough white membrane which needs to be stripped off before cooking.

Then they must be blanched and their tough outer membrane removed.

There are tough membranes in the centre of each one, which you need to remove with a sharp knife.

Force pulp through a strainer to remove any tough membranes.

This steak is covered in a tough membrane that should be removed before cooking.

Pericardium is a tough double layered membrane which covers the heart.

There's a tough membrane between the skull bone and the brain itself.

Still, the brain itself was not exposed; they looked through the hole at a tough inner membrane, the brain's final layer of protection.

The tough membrane that covers the brain had 100 million crystals per gram.