So maybe you caught my earlier post on burnt garlic oil. It is bitter and almost unpalatable on its own, but delicious when accompanying fatty and/or salt foods. It is traditional spooned over ramen and blends perfectly with the creamy broth.
Today, I played around with the burnt garlic oil some more. I wanted to try to tone down the bitterness and come up with more applications for the oil than just spooning it over the food. I decided that a foam would be a good idea because introducing air typically dilutes the flavor based on volume. Also, I thought, a black foam would look great on a plate.
To achieve a foam, the oil needs to be thickened to the point that it is strong enough to trap air. As far as I know, glycerin flakes is the only emulsifier that is fat soluble instead of water soluble. What this means is that glycerin flakes will dissolve and disperse directly into oil, while other emulsifiers require hydration and dispersion in water which then can be mixed into oil. To dissolve glycerin flakes, the oil has to be heated to at least 60C, or 140F. I found that about 8% by weight of glycerin flakes to oil created a product good for foaming.
Once the glycerin flakes is fully dispersed, pour into a whip cream dispenser, such as an iSi Whip, and load in two nitrous cartridges. The oil should be warm to the touch. Too hot and the foam does not hold and too cold and the oil congeals.
Results – I started with 100g in a .5 Liter capacity iSi Whip. One thing for sure is that I should have had the canister filled to near capacity. Maybe it was the viscosity of the oil but I had difficulty getting the oil down to the siphon and achieving a consistent stream of foam. The foam was dense, more like a mousse than a whipped cream. Very fine bubbles with a slick sheen. There was not as much volume increase as I thought there would be and therefore did not dilute the taste of the burnt garlic. Once it cooled to room temperature, the oil congealed slightly and the foam remained in tact. It is still very bitter when eaten on its own but tones down a lot more with a bit of salt. I will need to try it with food. A fatty fish or pork. Maybe along side thick cut, tender, smokey bacon.
Afterthought – I was looking for a foam and I got a foam but it was a lot denser than I wanted. I probably would not garnish a plate with it like I would a lighter foam with big luscious bubbles. However, I would treat it as I would a thick sauce or puree, swooshed on the plate with the rest of the components on top.
If I had to try again to make a lighter foam out of flavored oil, I would use soy lecithin dissolved in a little water then mixed into the oil. Perhaps my next experiment.