a lipidic polyester present in suberized plant cell walls that develop in the outer tissues of plants, where they play protective and insulating functions; term derived from Quercus suber, the cork-oak tree; upon depolymerization, cork suberin releases a complex mixture of monomers, namely, glycerol (14%) and long-chain ω-hydroxyacids (26%) and α,ω-diacids (45%), with dominant chain-lengths of 16, 18 and 22 carbons; used to make plant cell walls more visible to electron microscopy