slightest immediately after laying, and gets
stronger the longer it’s stored before cooking.
In general, egg age and storage conditions
have a greater influence on flavor than the
hen’s diet and freedom to range. However,
both diet and pedigree can have noticeable
effects. Brown-egg breeds are unable to
metabolize an odorless component of
rapeseed and soy meals (choline), and their
intestinal microbes then transform it into a
fishy-tasting molecule (triethylamine) that
ends up in the eggs. Fish-meal feeds and
certain feed pesticides cause off-flavors. The
unpredictable diet of truly free-range hens
will produce unpredictable eggs.
Something between 100 and 200
compounds have been identified in the aroma
of cooked eggs. The most characteristic is
hydrogen sulfide, H 2 S. In large doses — in a
spoiled egg or industrial pollution — H 2 S is
very unpleasant. In a cooked egg it contributes
the distinctively eggy note. It’s formed