more effective than polyethylene or PVC). In
the case of mashed avocado, this means
pressing the wrap directly into the surface.
Though not usually cooked — heat generates
a bitter compound and brings out an odd, eggy
quality — avocados are sometimes added at
the last minute to thicken and flavor soups,
sauces, and stews.
Sweet Corn The corn that we eat as a
vegetable is a fresh version of the same grain
that gives us dry, starchy popcorn and
cornmeal (chapter 9). Each individual grain
on an ear of corn is a miniature fruit that’s
mainly seed, a combination of a small
embryonic plant and its relatively large food
supply of storage proteins and starch. We eat
fresh corn about three weeks after pollination,
while the fruits are immature, their storage
tissues still sweet and juicy. Corn owes its
typical yellow color to carotenoid pigments,
including zeaxanthin (which derives its name