beaten into egg yolk plus water gives a sparse emulsion of coarse, unevenly sized oil droplets (left) Eight tablespoons/120 ml of oil give a tightly packed, semisolid emulsion of small droplets (right) The yolk emulsifiers and stabilizing proteins must be effective enough to withstand considerable physical pressure in order to prevent the oil droplets from coalescing into a separate layer Making Billions of Droplets from One Tablespoon It’s on account of surface tension, then, that the cook must pour energy into the liquid to be dispersed To make a sauce, its natural monolithic arrangement must be shattered And seriously shattered: when you beat a single tablespoon/15 ml of oil into a mayonnaise, you break it up into about 30 billion separate droplets! Serious whisking by hand or in a kitchen mixer provides enough shearing force to make droplets as small as 3 thousandths of a millimeter across A blender can get them somewhat smaller, and a powerful industrial homogenizer can reduce them to less than one thousandth of a millimeter The size of the droplets matters, because smaller droplets are less likely to coalesce with each other and break the sauce into two separate phases again They also produce a thicker, finer consistency, and seem more flavorful because they have a larger surface area from which aroma molecules can escape and reach our nose Two factors make it easier for the cook to generate small droplets One is the thickness of the continuous phase, which drags harder on the droplets and transfers more shearing force to them from the whisk Shake a little oil in a bottle of water, and the oil droplets are coarse and quickly coalesce; shake a little water in the more viscous oil, and the water gets broken into a persistent cloud of small droplets It’s helpful, then, to start with as viscous a part of the continuous phase as ... aroma molecules can escape and reach our nose Two factors make it easier for the cook to generate small droplets One is the thickness of the continuous phase, which drags harder on the droplets and transfers more shearing... on the droplets and transfers more shearing force to them from the whisk Shake a little oil in a bottle of water, and the oil droplets are coarse and quickly coalesce; shake a little water in the more viscous oil, and the water gets broken into a persistent cloud of small...somewhat smaller, and a powerful industrial homogenizer can reduce them to less than one thousandth of a millimeter The size of the droplets matters, because smaller droplets are