Molecular gastronomy is the logical result of merging food, physics and chemistry. While not the most common style of cooking, the results can be very impressive or disgustingly bland – or both. The problem is that it is all too often seen as some exclusive cult – limited to Michelin star fame. Fortunately this is not true for the amateur molecular gastronomer.
The more important obstacle is understanding what to do with food, something many chefs struggle with, using flashy food to compensate for lack of cooking skill. Looking at restaurants, it seems the three most common uses of molecular gastronomy are foams, “caviar” and sous-vide. Foams are used to create a light touch of a flavour for your food. Making foam can be done with
foam gelatine, however, an emulsifier can be simpler to use. Fortunately soy lecithin (non G.E. varieties are commonly available, cheaply, at health food stores) is a very useful emulsifier (something which keeps two things together), and perfect for foams. “Caviar” are small spheres, varying from the size of a pea to a walnut, surrounded by a gelatine like film with liquid inside; they are both a symbol of molecular gastronomy and already a cliché. Finally, sous-vide is a form of cooking food in a vacuum sealed bag in warm water for very long periods of time to preserve the flavours and constitution of food. Beginning with molecular gastronomy can be intimidating, and so to start, a foam is useful, simple and cheap, unlike “caviar” and sous-vide. Below is a recipe for Turkish coffee foam, a nice addition to many desserts, which can also be frozen for a light coffee sorbet.
- 1 tablespoon Turkish coffee powder (less if you don’t like strong coffee.)
- 1 to 2 tablespoons sugar (more if you don’t like bitter coffee.)
- 1 teaspoon lecithin granules (easily available at health stores)
- 175ml water
- 80ml milk
You can either make Turkish coffee properly if you have a cezve or you can use a pot. Either way, you will need to sieve the coffee before use to remove the dregs. To make Turkish coffee in a pot, simply put your coffee powder, sugar and half a cup of water in a pot, and while stirring, heat until the coffee starts to boil on medium to high heat.
Preparing soy lecithin can be difficult. Depending on what you use (there is lecithin for restaurants available that is easier to deal with) your lecithin may need some encouragement to dissolve into 50ml water, which can be done by placing it in a microwave on medium or low power for two minutes. If you do this, strain the excess lecithin that did not dissolve and keep the solution.
Mixing the milk, lecithin solution and coffee into a dish with a large surface area, and taking a stick blender so that the blade is half in the solution, and half in the air, blend on medium- low speed. Bubbles and foam will quickly form. An open dish is useful because good contact with air is necessary for foaming well.
Scoop off the foam and you are done. You should get a cup or two of foam, but there will be excess fluid, which you can drain off or blend to make more foam. The foam will last for a good half hour, but any longer may be pushing it. If you want you can freeze it for a light coffee sorbet.
The trick is to get the right amount of lecithin, which binds the air bubbles to the coffee by forming a thin sphere around the air bubbles, keeping the foam stable, rather than gelling in the bubbles, making the foam more solid, as with gelatine. Your mileage may vary and so it is important to experiment! Try some other drinks – cola and tea come to mind, but it is your experiment. Serve with ice cream or milkshakes for a little something extra. For more information, see khymos.org or watch some of Heston Blumenthal’s television shows. Think about how you could use some of the techniques, and try them out. You’ll be surprised.
You can find this article and many more in Issue 01 of Citizen Science Quarterly