On Food and Cooking

be firm or soft, slick or creamy, depending on
its egg content. The greater the proportion of
whole eggs or whites, the firmer and glossier
the custard. Extra yolks, or using yolks alone,
will produce a more tender, creamier effect. A
custard to be served in the container it was
cooked in can be as soft as the cook desires.
Those that are to be turned out of a container
for serving must be firm enough to stand on
their own, which means that they must contain
either some egg whites or at least 3 yolks per
cup/250 ml of liquid (the LDL-bound yolk
proteins are less efficient networkers than the
free-floating albumen proteins, so we need
more of them to make a firm gel). The
replacement of some or all of the milk with
cream reduces the proportion of eggs required
for a given firmness, since cream contains 20
to 40% less water and the egg proteins are
proportionally less diluted. Unmolding is
easiest from a buttered ramekin, and when the
custards have been allowed to cool