If you look at old meringue recipes - those dating from, say, 30 years ago - there's a consensus about the method, the quantities of sugar and egg and the temperatures at which they should be baked. But although the standard 100g egg white to 200g sugar can't be faulted, cooking has evolved since the 1970s. With a few exceptions, restaurants these days don't go in for Baked Alaska and vacherins.
Chefs such as Daniel Galmiche of Harvey's in Bristol and his pƒtissier, Laurent Pierre, use meringue differently from the way their predecessors did. They need a basic mixture that is stable, regardless of how it's spread or otherwise handled: it mustn't be too sweet. And though it might be dried in the oven, it won't be baked.
That's why they prefer to make a cooked Italian meringue rather than the raw Swiss meringue taught by the old school - the Swiss version still makes the classic plump, tawny meringue shells better, but is not what today's chefs need.
Italian meringue once had specific uses. It was a component of iced soufflés and the topping on lemon meringue pie and other similar desserts. The method was to whip the whites first, then pour boiling sugar on to them. At Harvey's the chefs use a third less sugar than most textbooks insist on, and they pour it on to the whites when they start whisking them. It's a simple, practical and foolproof method.
The benefit is that the mixture can be piped fine, spread as thin as a wafer or folded into mousseswithout being cloying. Nuts or other flavourings can be added - anything from cocoa powder to peppercorns. It doesn't break up as uncooked meringuecan, and it keeps for several days without any lossof quality.
Italian meringue structure
A meringue expands to about eight times the original volume of the egg white. It's a foam made of air trapped in a network of bonded water and protein bubbles. Whisk the white long enough, and the bubbles will burst and the meringue collapse. Adding sugar makes the foam more stable and longer-lasting, although it will still separate eventually.
When boiling sugar is added to egg white, as in Italian meringue, it coagulates (or cooks) part of the egg's protein, preventing the bubbles from bursting. They bind to each other better, while holding the air.
Basic Italian meringue
Speak to almost any pastry cook who has learned his craft in Britain, and he will have two meringue recipes in his repertoire. He will make Swiss meringue from uncooked egg white and sugar and Italian meringue from boiling sugar poured on egg white. For both he will measure two parts of egg to one part of sugar. This is easy to remember, but it's too sweet for the modern desserts served at Harvey's. And by using less sugar in his meringue, Pierre also increases its volume and improves its texture.
The fresher the eggs, the more body the meringue has. A good free-range egg might make a marginal difference - give more volume - but it is not essential.
When separating the eggs, ensure no yolk or fat mixes with the white. A single speck is enough to stop the meringue forming. It's the first rule every college student learns about egg whites - and it's true.
Chefs believe copper mixing bowls make better, more stable meringue, and, in fact, scientists have shown that egg white whisked in copper receptacles is less liable to collapse. The benefit, though, applies only to raw white - it won't materially influence cooked Italian meringue.
It is essential to washÁ bowls thoroughly so that no trace of fat remains. To be on the safe side professional bakers steam-clean bowls before use.
Pastry cooks often believe cube sugar is more refined and gives a better finish when boiled. Caster sugar is more commonly used in pƒtisserie, but a granulated sugar is not noticeably inferior.
Salt and vinegar
Chefs often add a squeeze of lemon juice, a little vinegar and/or salt when whisking egg whites. Do these traditional tricks make a difference? Acid won't give a foam extra volume, but it does help prevent a raw meringue collapsing. Salt, on the other hand, not only reduces volume but also lengthens whisking time. n