On Food and Cooking

vegetables are a major exception: starch
granules in the cells absorb all the free
moisture in the tissue, and are best left intact
in unbroken cells so the solid puree doesn’t
become gluey. See the discussion of mashed
potatoes on p. 303.) Purees are made into
sauces and soups, frozen into ices, and dried
into “leathers.” For purees as sauces, see p.
620.
Many ripe fruits have sufficiently
weakened cell walls that they are easily
pureed raw, while most vegetables are first
cooked to soften the cell walls. Precooking
has the additional advantage of inactivating
cell enzymes which, when cellular
organization is disrupted, would otherwise
destroy vitamins and pigments, alter flavor,
and cause unsightly browning (p. 269). The
size of solid particles in the puree, and so its
textural fineness, is determined by how
thoroughly ripening or cooking have
dismantled the cell walls, and by the method