B. Properties of triglycerides
Triglycerides, and therefore fats and oils, differ in their
stability, viscosity and melting point. The properties of any
specific TG molecule depend on the particular fatty acids that
constitute it. Different fatty acids are composed of different
numbers of carbon and hydrogen atoms (see Fig. 2). The
carbon atoms, each bonded to two neighboring carbons, form a
flexible zigzagging chain. Fatty acids with longer chains are
more susceptible to intermolecular forces of attraction (in this
case, van der Waals forces), rising their melting/pour point and
viscosity, and those of related fatty esters. On the other hand,
because of rigid kinks inserted by double bonds in the FA
carbon chains (see Fig. 2), unsaturated TGs cannot stack
themselves in a closely packed arrangement as saturated TGs
do, so they flow and freeze less easily and are typically liquid
at room temperature. For example, animal fats (tallow and lard)
are high in saturated FA content and are solids; olive and