On food and cooking the science and lore of the kitchen ( PDFDrive ) 1190

afteranemulsionhasformedand
developedsomeviscosityshouldtheoil
beaddedmorerapidly.
Theproportionsofthetwophasesmust
bekeptinbalance.Formostemulsified
sauces,thevolumeofthedispersedphase
shouldn’texceedthreetimesthevolume
ofthecontinuousphase.Ifthedroplets
arecrowdedsocloselytogetherthatthey
areincontinuouscontact,thenthey’re
morelikelytopooltogether.Whenthe
consistencyofanemulsionbecomes
stiff,thisisasignthatthecookshould
addmoreofthecontinuousphasetogive
thedropletsmoreroom.
Starting Slowly There’s a simple reason for
starting the emulsion slowly and carefully,
withsmallamountsofthedispersedphase.In
theearlymixing,whenlittleornooilhasyet
beenemulsified,it’seasyforlargedropletsto
avoid the churning action of the whisk and


collectatthesurface.Ifalargevolumeofoil
is added before the previous one has been
fully emulsified, then the bowl may end up
with more unemulsified oil than water. The
oil then becomes the continuous phase, the
normallycontinuouswaterbecomesdispersed
init,andtheresultisaninside-outemulsion,
oily and runny. By whisking in the first

portionofoilinsmalldoses,thecookmakes
sure to produce and maintain a growing
population of small droplets. Then when the
rest of the oil is incorporated more rapidly
into the already well-emulsified system, the
existing droplets work as a kind of mill,
automaticallybreakingdowntheincomingoil
into particles of their own size. In the last
stagesofsaucemakingthecook’swhiskneed
notbreakuptheoildropsdirectly,buthasthe
easier job of mixing the new oil with the
sauce,distributingitevenlytoallpartsofthe
droplet“mill.”