Initial Experiments in Molecular Gastronomy

2012.01.21 in fooding

A while back, I watched the No Reservations episode filmed surrounding the final days of el Bulli; the Catalonian restaurant often called the best in the world.

Since then, in the back of my mind, I've known that food can be more interesting than we usually make it, through the introduction of chemistry! Those who know me probably realize that the passion and culture of the food (which drove el Bulli) wouldn't be nearly as exciting to me as the application of science — not the most noble reasoning, and certainly not the takeaway anyone involved in that episode intended, but still very exciting from my perspective!

I left that knowledge alone for a while, moved out here, and became extremely lazy about cooking. Recently, though, I decided I'd play with some of the basic techniques of molecular gastronomy, just to see how it worked. After some trouble I managed to acquire a supply of basic ingredients — after all, they're not the kinds of things you can easily find in an ordinary grocery store.

I'm beginning with just the simplest techniques first, attempting to learn separate components before combining them into anything actually interesting. I imagine what I've managed so far might appear more boring than normal food, from the outside, but the possibilities are what excite me!

In fact, I've tried just two techniques so far, out of the many yet invented — the simplest: spherification and gelification, and only in their most basic forms.

Spherification

Spherification involves constructing a skin around a liquid, using calcium lactate and sodium alginate.

1/3 cup lemonade
4 grams C6H10CaO6

The target liquid is combined with calcium lactate, then frozen in small spherical portions. I chose lemonade simply because it was on hand, and seemed like a reasonable liquid to have "exploding" in your mouth.

1/4 cup water
2 grams NaC6H7O6
Next, the sodium alginate is dissolved in water, to make the spherification bath. While the spheres are freezing, the bath is refrigerated.

Once the spheres are completely frozen, they are removed from their molds, and dropped into the bath. After a few minutes, they are removed from the bath and washed in water, to prevent further growth of the skin.

Once the spheres have completely melted, they are ready for consumption:



There are a few things that I'm planning on changing next time:
  1. I left my spheres in the sodium alginate bath for too long; the skin was slightly thicker than I'd have liked. My understanding is that the reaction that creates the skin continues until it's removed from the bath and washed.
  2. The skin of my spheres was not particularly smooth. I believe that a rounder and smoother mold might have helped with this. Also, I didn't have a powered hand mixer to combine the sodium alginate and water; a more well-mixed bath might have helped in the smoothness department.
  3. There were air pockets in all of my spheres! They floated in the sodium alginate bath; I need to find a way to suspend them deeper without impacting their shape.
  4. My spheres were a bit too big. Luckily, there's an easy solution to this!
Verdict: more experimentation required! (and yet still delicious)

Gelification

While both gelification and spherification are often used to make spheres, there's one key difference: gelification involves turning the entire material into a gel! Agar is the key ingredient in this process; the same algae-derived material used to keep microbes happy on petri dishes!

Conveniently, gelification is extremely simple; a target liquid is heated to boiling, and usually watered down somewhat. Agar is added, in its powdered form, and mixed in thoroughly. This mixture is then shaped as desired, and then cooled; agar is a liquid above 85°C, so the cooling process is the key to bringing it back into its solid state.

The shaping process is where most of the differentiation happens; one relatively easy shape to make is tiny spheres, resembling caviar. In order to make small spherical gels, a mechanism for creating droplets of liquid is required. After reading a bit, I found that people commonly use chilled vegetable oil. In the end, using a pipette to drop the near-boiling liquid mixture into oil that had been sitting in the freezer for a while turned out to do just the trick:

1/3 cup water
1/2 cup honey
2 grams agar



Once the supply of boiling honey is depleted, the spheres are retrieved and washed in water.

After making "honey caviar", I made a few notes to myself:
  1. The balls were extremely uneven. I had used an unfortunately large and hard to control pipette; for later experiments, I found a more appropriate one, with a small tip.
  2. The honey taste was extremely subtle; perhaps cutting down on the water would help.

I took another stab at gelification today, in the construction of a ridiculously time-consuming burger:

1/4 cup water
1/2 cup mustard
2 grams agar

1/4 cup water
1/2 cup ketchup
2 grams agar

The only difference between the preparation of the ketchup and mustard was in the cooling stage; the ketchup was cooled in the same way as the honey; dropped from a pipette (more appropriately sized this time!) into freezer-chilled vegetable oil. The mustard, on the other hand, was fed into surgical tubing, which I then placed in ice water. After a few minutes I used a syringe to force air into one end of the tube, slowly forcing the mustard out the other, leaving behind a stringy spaghetti-like condiment that was so solid it could be picked up in your hands!

The two were then combined to great effect:



I'm quite pleased with how this, my third experiment, turned out; still, there are many more left to be done! If you have any ideas, let me know!