changeable. Pureeing mixes the cell contents
with each other and with oxygen in the air, so
enzyme action and oxidation begin
immediately (see below for the effects in
cooked purees of tomato, a botanical fruit).
The best way to minimize this change is to
chill the puree, which slows all chemical
reactions.
Raw Purees: Pesto The Italian puree of basil
leaves, pesto genovese, also contains olive oil
and so is partly an emulsion as well. Pesto
takes its name from the same root that gives
us pestle, and the basil leaves and garlic were
traditionally ground with a pestle and mortar.
Because this takes some time and effort,
modern cooks usually prepare pesto in a
blender or food processor. The choice of
appliance and how it’s used influence both
consistency and flavor. The crushing and
shearing action of the pestle, the shearing
action of the blender, and the slicing action of