Chopping onions
"First take an onion..." is an instruction that begins countless recipes. But the chemistry of the onion, its ability to build bridges for other ingredients and the way its chemical nature changes with different styles of cooking, is only partly understood.
For example, to develop the full, concentrated sweetness of onion, it needs to be melted in butter or oil before adding other ingredients. Salt makes it weep and stops it browning, and acids – lemon and tomato – prevent it softening. But recipes often skate over this fine detail and onions often end up undercooked and indigestible.
I’ve got into the Spanish habit of storing onions fried to melting in olive oil in the fridge. Covered and immersed in oil, they keep for several days and save time for quick suppers.
Another favourite is onion marmalade. It takes up to an hour to cook several large onions in olive oil into a soft, dark pulp and another 30 minutes with red wine or red wine vinegar. It keeps safely in a sterilised jar in the fridge for several weeks and is wonderful with pate and terrines.
TV chef Henry Harris adds fresh orange juice and serves it with foie gras at Racine in Knightsbridge and Pascal Aussignac of Michelin starred Club Gascon in Smithfield, adds lemon thyme and uses it to season courgette and tomato gratin. Try it too with mature Cheddar or one of the tempting British blue cheeses described in Juliet Harbutt’s seminal World Cheese Book.
Finally, there's a great variation on the French onion sauce 'soubise' that Trish Hilferty and Tom Norrington-Davies give their new book Game, A Cookbook. They use bread sauce seasonings to flavour onions stewed in milk to make this sauce and serve it with roast quails on toast, an idea to copy with chicken and other game.
Time out on tears
Q: I suffer terribly when peeling onions, tears streaming down my face. Is there a solution? I have noticed that some onions are worse than others.
A: The answer lies in the soil. Onions collect sulphur from the earth and turn it into highly volatile molecules called amino acid sulfoxides. When you peel then slice into an onion, these are released and instantly irritate the eyes and nose.
Sulfoxides are water soluble so it helps to peel onions under water but they still have to be sliced or chopped. Leaving the root end intact can help, and so does chilling.
Some onions are worse than others and as a general rule, the smaller the onion, the stronger the aroma. Contact lenses and swimming goggles work for some people but I’d love to hear your tips for peeling onions without tears.
Safety tip: always peel and chop onions with a sharp knife; a blunt one can easily slip off the tough, shiny skin and cause an injury. Another tip is to halve or quarter medium or large onions before peeling or chopping.
Saga Book Shop
Game, a Cookbook by Trish Hilferty and Tom Norrington-Davies. Buy this book at a discount from Saga Books
World Cheese Book by Juliet Harbutt. Buy this book at a discount from Saga Books
This article was first published in the February 2010 edition of Saga Magazine