Abstract: A selective adsorbent for the separation of organic material from solution comprises adsorbent particles and magnetic particles embedded in a porous matrix of organic polymeric material, the porosity of the matrix being selected so as to allow only molecules of up to a certain order of molecular weight to enter into the interstitial structure of the matrix whereby the composite material functions selectively to adsorb dissolved materials from solution. The adsorbent is useful, inter alia, in the food processing industry where trace quantities of materials need to be separated from complex mixtures.