What is Suberin?

Suberin is a waxy substance found in a number of plants and trees. It is named after the Latin for the cork oak tree – Quercus Suber.

The main property of suberin is that it is highly hydrophobic or in other words water resistant. Plants use suberin for a variety of purposes connected to water. For example mangroves use suberin to minimize salt intake from their littoral habitat.

In the case of the cork oak, suberin is found in the dead bark, and in particular in the phellem layer or the outer layer of the bark. This is to stop moisture being lost by the tree.

It is this suberin in the bark of the cork oak that makes cork the perfect material for wine bottle stoppers. Because of the suberin in cork the wine stopper is water resistant enough to stop wine permeating the cork. Also the natural springiness or elasticity of cork means that it can be condensed and put in the neck of a wine bottle. Once in the neck it expands to make a water and air tight seal.

The suberin in cork is also useful for cork flooring. It makes the flooring water resistant. Small amounts of water will ‘sit’ on the flooring instead of soaking in, giving you time to mop up the spill.

Another useful property that suberin gives to cork flooring is that cork flooring is fire retardant. The waxy substance is resistant to fire. It is hard to set alight, and in the event of a fire cork flooring does not give off any toxic fumes.

So to sum up, suberin is a very useful substance that is vital to the survival of the cork oak tree. It provides water resistance in cork flooring and makes cork flooring non-flammable.