A mixture of a polyester, such as poly(ethylene terephthalate) PET, or a polyamide, and a suitable stabilizer selected from the group consisting of hydroxylamine stabilizers, substituted hydroxylamine stabilizers, nitrone stabilizers and amine oxide stabilizers, when extrusion compounded exhibits a lower residual acetaldehyde content than does polyester or polyamide alone when similarly treated. The invention pertains to any polyester or polyamide used in the manufacture of molded articles, fibers or films, for instance bottles or containers which are used to store consumer materials, for example food, beverages and water.