construction of their cell walls, and the
amount of water held in by those walls.
The cell walls of our fruits and vegetables
have two structural materials: tough fibers of
cellulose that act as a kind of framework, and
a semisolid, flexible mixture of water,
carbohydrates, minerals, and proteins that
cross-link the fibers and fill the space between
them. We can think of the semisolid mixture
as a kind of cement whose stiffness varies
according to the proportions of its ingredients.
The cellulose fibers act as reinforcing bars in
that cement. Neighboring cells are held
together by the cement where their walls
meet.
Crisp Tenderness: The Roles of Water
Pressure and Temperature Cell walls are
thus firm but flexible containers. The cells
that they contain are mostly water. When
water is abundant and a cell approaches its
maximum storage capacity, the vacuole swells