This recipe appeared on Le Scienze blog (the Italian edition of Scientific American magazine).
Dario Bressanini is a chemist that writes a very engaging column for this magazine called La Scienza in cucina (Science in the kitchen) about the most common chemical reaction happening in the kitchen.
This is the link for the original article
The recipe is for French meringues, very simple if you follow scrupulously all the rules.
Ingredients :
100 gr of egg whites
between 100 a 200 gr of icing sugar
1 tsp of lemon juice or ½ tsp of cream of tartar
Method :
Preheat the oven at 85 C
1. It's best if using fresh eggs, the older the eggs the less stable will be the foam.
2. Weight the egg whites in a bowl that's squeak clean, without a speck of grease, Bressanini suggest to avoid plastic bowls as because of its chemical structure it attracts grease hence harder to clean, he says to use a stainless steel bowl (i used my glass Kitchen Aid bowl).
3. French meringues have a ratio of egg whites: sugar that's 1:1 or 1:2, if you like a crunchy outside and a chewy core use the first ratio but i like mine very crisp (unless i'm making a Pavlova) so i used the 1:2 ratio.
4. Acidic ingredients play a central role to help reaching the perfect foam. You can use Cream of Tartar ( Potassium acid tartrate) or lemon juice (citric acid) that will give the meringues a beautiful candid colour.
5. Don't add salt, i repeat, don't add salt! Contrary to common belief (guilty) the salt will destabilise the foam.
6. Whisk the whites with a stand mixer or an electric whisk to soft peaks or until the volume is four times the initial volume.
7. Add the sugar and cream of tartar little by little while mixing, the sugar has to dissolve completely.
8. Beat the egg whites until you have stiff peaks.
9. Transfer the meringue in a piping bag and pipe them on a baking tray covered with greaseproof paper.
10. Transfer into the oven at 85 C for 2 / 3 hours.
Let me know if you make them!