Culinary Foam – An introduction
In the past decade, there has been an up going trend among chefs in the usage of culinary foam made famous by Ferran Adria of elBulli fame. There are two schools of thoughts among chefs regarding food such as culinary foam. On one side, the old guards believe food should be wholesome, natural, with minimal meddling around with. The other school, which proclaim itself as “progressive cuisine”, embraces all things new that would help in the advancement of gastronomy. Stuffs which not look out of place in a scientific laboratory like a centrifuge, rotary evaporator, test tubes and liquid nitrogen are becoming the norm in such experimental kitchens.
We are not here to debate who is right. I believe that as long as such modern techniques contributes something to the dish and makes it even better, it has served its purpose. Putting culinary foam must make sense to the food, and not just for the sake of putting some little foam here and there just because it looks pretty.
Today, we will talk about the science of culinary foam, its usages, and maybe show a recipe or two on it.
Culinary Foam – The science of culinary foam
Why do we use culinary foam?
Culinary foam is like a sauce thickened by air. For me, I use culinary foam when I want to impart a light aromatic flavour to the food when a liquid sauce will be pooling unsightly all around the plate. It also lends a unique contrast to the textures of the food. As an added bonus is, it’s visually exciting.
Making culinary foam is very easy. You just blend or whisk the liquid at high speed, and hey presto… there you get it. But wait… after a few seconds it simply disappears…
Making culinary foam is easy, maintaining or stabilizing it is the harder part which takes some scientific knowledge. To make culinary foam, you need to introduce bubbles into the liquid by means of agitating it, there are many methods of doing it such as – blending it at high speed in a blender, whisking it hard enough, pumping it with gas in a whipping canister, or even using a fish tank pump to create bubbles.
The bubbles created will be very short-lived and highly unstable if there is no stabilizer to hold them in place. The bubbles generated will quickly coalesce and burst. Pure water does not provide bubble stability, and you should be very much concern if your drinking water is able to hold bubbles!
As chefs, we need to hold culinary foam until the food gets to the dining room and reaches the guests. We do this by introducing a surfactant into the liquid so as to coat the surface of air bubbles and water, and create a thin barrier between surrounding bubbles to prevent them coalescing. There are many edible stabilizers or surfactant which can temporarily stabilize culinary foams in the kitchen. Common stabilizers are proteins from eggs, lecithin, gelatine, and emulsified fat.
Culinary Foam – Video on making culinary foam
In this video, I demonstrated by using water as the base liquid as it is neutral. As can be seen in the video, I tried blending just the water itself but the bubbles won’t hold. I then add de-oiled lecithin powder, which is a surfactant into the water and blend again. This time, the culinary foam came out beautifully. I then aromatised it by grating some lime zest over it
You can use other liquid like juices, tea, and herb-infused liquid instead of water. The possibilities are endless. But do take note that the base liquid needs to be very intense as the air incorporated will dilute its flavour. Lecithin works well only in a non-fat environment. So if your base liquid contains any fat, other surfactants such as protein, gelatine, hydrocolloids, sucro, or emulsified fat should be used instead.
The photo above is the culinary foam in the video after ten minutes. As can be seen, it still holds its shape beautifully.
Culinary Foam – Recipes to try:
225 grams lime juice
275 grams water
1.5 gram lecithin (0.3%)
Combine the three ingredients and use a hand-held mixer on the surface of the liquid; allow to stabilise for one minute and collect the air that has form on top.
Recipe by Texturas elBulli
500 grams milk
100 grams muscovado sugar
10 grams Earl Gray tea
5 grams lecithin (0.83%)
Bring milk and sugar to the boil, infuse tea for four minutes. Strain, add lecithin, and froth with a hand-held blender. Allow to stabilise for one minute and collect the air that has form on top.
Recipe by The Chef Story.
Now that you know how culinary foam is made, try playing around with it to add some excitement to your food.