On food and cooking the science and lore of the kitchen ( PDFDrive ) 1493
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oceans.Ourbodiesare60%waterbyweight;
rawmeatisabout75%water,andfruitsand
vegetablesupto95%.
WaterClingsStronglytoItself
Theimportantpropertiesofordinarywater
canbeunderstoodasdifferentmanifestations
ofonefact.Eachwatermoleculeis
electricallyunsymmetrical,orpolar:ithasa
positiveendandanegativeend.Thisis
becausetheoxygenatomexertsastronger
pullthanthehydrogenatomsontheelectrons
theyshare,andbecausethehydrogenatoms
projectfromonesideoftheoxygentoforma
kindofVshape:sothere’sanoxygenendand
ahydrogenendtothewatermolecule,andthe
oxygenendismorenegativethanthe
hydrogenend.Thispolaritymeansthatthe
negativeoxygenononewatermoleculefeels
anelectricalattractiontothepositive
hydrogensonotherwatermolecules.When
thisattractionbringsthetwomoleculescloser
toeachotherandholdsthemthere,it’scalled
ahydrogenbond.Themoleculesiniceand
liquidwaterareparticipatinginfromoneto
fourhydrogenbondsatanygivenmoment.
However,themotionofthemoleculesinthe
liquidisforcefulenoughtoovercomethe
strengthofhydrogenbondsandbreakthem:
sothehydrogenbondsinliquidwaterare
fleeting,andareconstantlybeingformedand
broken.
Thisnaturaltendencyofwatermolecules
toformbondswitheachotherhasanumberof
effectsinlifeandinthekitchen.
Water molecules. Here are three different
ways of representing a molecule of water,
which is formed from one oxygen and two
hydrogen atoms. Because the oxygen atom
