Xanthan gum

The chemistry of the perfect coffee foam The Caffe Shakerato is often overlooked in modern coffee bars, yet it remains the gold standard for summer espresso drinks. James Hoffmann argues that the drink's simplicity is its greatest asset, provided you master the aeration. When you shake hot espresso with ice, you aren't just cooling it; you are creating a stable micro-foam. While some traditionalists insist on granulated sugar to assist this process, testing proves that a simple syrup is superior. Syrup ensures total dissolution, providing a consistent sweetness that granulated sugar often fails to deliver in a cold environment. Precision tools for the classic build To execute the classic version, start with a double espresso (approximately 40g). You will need a cocktail shaker—preferably a large set of shaker tins to avoid the pressure build-up that can pop the lid off smaller vessels. Add 10g of a one-to-one simple syrup and two drops of a 20% saline solution. This salt content is crucial; it suppresses the inherent bitterness of chilled coffee without making the drink taste salty. Shake vigorously with plenty of ice to maximize aeration, then strain into a chilled glass. For a cleaner texture, double-strain through a fine mesh sieve to catch stray ice shards. Elevating aromatics with Earl Grey and bitters For those seeking more complexity, James Hoffmann suggests a fruit-forward variation. This involves pulling a slightly tighter, more acidic shot from a washed coffee, perhaps from Ethiopia or Rwanda. Instead of plain syrup, use an Earl Grey-infused syrup and 0.2g of orange Angostura bitters. The bergamot notes and botanical complexity of the bitters marry perfectly with the high acidity of the espresso, resulting in a sophisticated, tea-like coffee cocktail. Batching for efficiency with nitrous and xanthan The final evolution addresses the workflow bottleneck of shaking individual drinks. By using a cream whipper and nitrous oxide, you can batch five double espressos at once. The addition of xanthan gum at a precise 0.05% concentration stabilizes the foam, giving it a rich, creamy mouthfeel that mimics dairy. Charging the canister twice—discharging the first to remove oxygen—prevents oxidation, keeping the coffee fresh for hours in an ice bath. This modernist approach allows a high-volume cafe to serve a perfect Shakerato with the speed of a nitro tap.