When I first came to Britain nearly three decades ago, one of the (many) things I found strange was carrot cake. Carrot, for me, was something you pickled with oriental cabbage in kimchee, boiled in Japanese-style kare or fried with other vegetables for japchae (Korean glass noodles fried with julienne of vegetables and meat). It was not something you put in a dessert. Carrot cake is now one of my favourites but initially it was the equivalent, say, of Brussels sprouts crumble or cabbage cheesecake for a Brit, proving that so many of our ideas about how a food ingredient should be used are culturally specific.

Carrot, which originally comes from central Asia (probably Afghanistan), used to be yellow, white or purple. The orange variety, which is now the dominant one, was developed in the Netherlands only in the 17th century.

The orange colour of the carrot is given by beta-carotene, which turns into vitamin A when taken internally. In 2000, a group of scientists led by Ingo Potrykus and Peter Beyer transplanted carrot genes into rice and created the so-called golden rice, which is rich in vitamin A, unlike natural rice. Poor people in rice-eating countries eat little other than rice and therefore suffer from vitamin A deficiency, which is estimated to be responsible for up to two million deaths, half a million cases of blindness and millions of cases of xerophthalmia, the debilitating eye disease, every year.