Fernet with Pineapple Foam
An exercise in molecular minimalism.
To make a good foam, one needs to a balance the ratio of sugar to acid, not merely for flavor, but also for the structural integrity of the foam. Pineapple juice has a pH of about 3.0, whereas lemon juice hovers between 1.8 and 2.2. I used pineapple juice as the base of this foam, so I knew I needed to use significantly less citrus than in the whiskey sour foam from before, but I wasn't sure how much less. I ended up taking a stab in the dark, and getting lucky. Pineapple juice also has a high sugar content, so one wonders if it might not be fine on its own.
Pineapple Foam
6 oz Fresh Pineapple Juice, strained.
1 oz Fresh Lime Juice, strained.
1 oz Simple Syrup
2 oz water
4 egg whites
Combine all in an iSi whipped cream dispenser and discharge two nitrogen cartridges.
Allow the canister to rest in the refrigerator for ten minutes before use.
Old Fashioned Fernet Cocktail, Pineapple Foam
1.5 oz Fernet Branca
.25 oz Simple Syrup
1 Dash Angostura Bitters
Stir over ice and strain into a rocks glass with a single large ice cube.
Top with a generous amount of pineapple foam.
This drink needed nothing. Perhaps instead of an old fashioned, it should be called a new fangled, in reference to the molecular mixology technique here employed. Regardless, this was one of my finest original creations to date. The water mellowed out the flavor of the foam, balancing it against the Fernet, allowing the whole drink to breathe. A big danger with foam drinks is that the foam can overwhelm the drink underneath, and dilution of the foam is the secret to keeping the flavors in balance.