Description
A foam composed of calcium-alginate bubbles, set via reverse spherification to create delicate, bursting textures.
Technical
Sodium alginate is dispersed in a flavorful liquid (pH > 3.5), then whipped into foam; calcium ions diffuse from a bath to form semi-permeable membranes around air pockets. Key reactions include alginate cross-linking (Ca²⁺ + alginate → gel) and foam stabilization via protein-polysaccharide interactions.
Culinary Significance
Creates ethereal, flavor-packed bubbles that dissolve on the tongue, ideal for avant-garde dishes or cocktail garnishes.
Science
Primary Reaction
Ionic cross-linking of alginate
Parameters
Temperature
18°C optimal
4°C to 60°C range
Time
90 sec
30 sec – 3 min
Equipment
Whipping siphonPerforated spoonpH meter