Emulsification (Emulsion)
Emulsification
Japanese: 乳化（エマルション）
A stable state where normally immiscible water and oil mix as fine particles. A colloidal phenomenon involved in the texture of mayonnaise and miso.
Emulsification is the phenomenon where two immiscible liquids—like water and oil—form a stable mixture with one dispersed as fine particles in the other. Mayonnaise (using egg yolk lecithin as emulsifier) and milk are classic examples.
Miso also involves emulsification. Soy-derived lipids and water are dispersed with soy lecithin and degraded proteins (peptides) as emulsifiers. This emulsified state contributes to miso's smoothness and body.
When dissolving miso in soup, oil droplets dispersing throughout rather than floating is the power of emulsification. As aging progresses and protein breakdown advances, peptides involved in emulsion stability increase, achieving more uniform dispersion. The invisible way things 'mix' determines miso's mouthfeel.