On Food and Cooking

fearing” substances. The reason for this is that
carbon and hydrogen atoms pull with a similar
force on their shared electrons. So unlike the
oxygen-hydrogen bond, the carbon-hydrogen
bond is not polar, and the hydrocarbon chain
as a whole is nonpolar. When polar water and
nonpolar lipids are mixed together, the polar
water molecules form hydrogen bonds with
each other, the long lipid chains form a
weaker kind of bond with each other (van der
Waals bonds, p. 814), and the two substances
segregate themselves. Oils minimize the
surface at which they contact water by
coalescing into large blobs, and resist being
divided into smaller droplets.
Thanks to their chemical relatedness,
different lipids can dissolve in each other.
This is why the carotenoid pigments — the
betacarotene in carrots, the lycopene in
tomatoes — and intact chlorophyll, whose
molecule has a lipid tail, color cooking fats
much more intensely than they do cooking