Description
Mechanical shear forces applied to hydrocolloid gels (gellan/agar) disrupt polymer networks, creating fluid yet fibrous textures.
Technical
Shearing breaks the brittle gel matrix into micro-strands while retaining viscosity via residual polymer entanglement. Gellan gum (high-acyl) is preferred for its shear-thinning properties and thermal stability. Agar requires precise shear rates to avoid complete liquefaction.
Culinary Significance
Used to create 'fluid gels' for sauces with body, or fibrous textures mimicking plant/meat structures. Enables heat-stable foams and stable suspensions without gumminess. Critical in modernist vegan dishes for mouthfeel.
Science
Primary Reaction
Polymer network fragmentation under shear stress
Parameters
Temperature
°C to °C range
Too cold increases viscosity; too hot risks melting
Time
1-2 min (pulsed shear)
15 sec (high shear) – 5 min (continuous shear)
Equipment