SUMMARYRapid in vitro polymerization of the cutin acids of “Golden Delicious” apple skin is possible at a temperature of 100 °. The resulting polymers can be hydrolyzed so that the original constituents are obtained again. Not all the acids participate in the polymerization in the same way: after two days the concentration of monobasic acids in the polymer was low compared with the concentration of the hydroxy fatty acids. Pigmented material from the cuticle layers influences the elasticity of the polymer but has little influence on the polymer‐air surface str