The membranous brown fronds of laver can be found at low tide, covering rocks like discarded plastic bags. Impossible to eat raw, laver must be cooked for a heroic 10 hours. Only then will the cell structure break down to release the intense umami flavour locked inside. The result of all that cooking is a sticky, brown paste known as laver bread, which people either love or hate. An almost identical species, Pyropia yezoensis, is cultivated in the Far East in the millions of tons. This is not used to make an oriental laver bread, but
nori, the black papery covering of sushi rice. It was a difficult species to cultivate until breakthrough work by the English phycologist, Kathleen Mary Drew-baker in 1949, when she published the life cycle of Porphyra species. This formed the basis of a multi-billion-dollar industry and Drew-baker is honoured in Japan with a monument and the impressive title ‘mother of the sea’.