Fruit of the sun

Citrus. A history 

Pierre Laszlo 

Chicago, US: University of Chicago Press 2007 | 252pp | ?13.00 (HB) ISBN 9780226470269 

Reviewed by Tony Onyett

Pierre Laszlo taught chemistry at Princeton and Cornell in the US, the University of Liege, Belgium, and the Ecole Polytechnique, near Paris, France, but is now a popular science writer. He has previously written about salt and also science writing and communication. His writings combine a wide knowledge of science, history and art that I find particularly fascinating. 

Laszlo’s latest book, on citrus fruit, takes the reader on a journey around the world from Asia, through North Africa to Spain and Portugal to the Americas, especially to Florida and California, and through centuries of history. The three basic species of citron, pummel and mandarin have been extensively hybridised to produce the huge number of cultivated citrus varieties grown today. Laszlo traces these developments in the Old and New Worlds and gives special attention to the two most widespread commercial citrus products - lemonade and orange juice. 

Laszlo’s chemical background comes out in his description of the identification and later synthesis of vitamin C, especially the biographical details on the Hungarian Albert Szent-Gy?rgyi, who received a Nobel prize in 1937 for his identification of the vitamin and the American Charles Glen King who, quite rightly, did not. 

The peel of citrus fruit, so often thrown away, is also the source of many terpene chemicals, especially limonene, which are widely used in the food and cosmetics industries. Laszlo devotes a chapter to this valuable part of the fruit.  

Finally, chemistry also comes to the surface in the chapter dealing with that staple of the healthy breakfast - refreshing orange juice. Laszlo describes in detail its widespread commercial adulteration, since the term orange juice covers a multitude of products from ’freshly squeezed’ to ’frozen concentrate’ and the thick sickly mixture with high-fructose corn syrup so beloved by children.  

There are chapters on citrus fruit in art, literature and culture (including the orange-throwing festivals in Ivrea in Italy and Binche in Belgium), and its preservation in marmalades, candied products, alcoholic beverages and chutney. 

Overall this is a highly readable account about fruit which most of us have eaten and enjoyed in one form or another, with some recipes and culinary tips for the reader who wants to experiment further.