BACKGROUNDSpray congealing is investigated as a new innovative immobilization technique for biocatalysts. The immobilization is realized by atomization of a mixture of a melted carrier and the enzyme, which is re-solidifyed due to temperature decrease. This method needs neither organic solvents, nor difficult downstream processing after preparation. For the encapsulation of different matrices, long chain alcohols and glyceryl derivatives, with melting points below 86 degrees C and environmentally friendly properties, are chosen and tested for their suitability for enzyme encapsulation. RESULTSThe immobilization of a laccase (EC 1.10.3.2, Novozym 51003, from Myceliophthora thermophila) was investigated and the produced microparticles were characterized. The obtained particles showed a mean particle size around 40m and a spherical surface with different structures depending on the used matrix. Spray congealing with the laccase reached yields of 80% and residual activities up to 56%. Furthermore, four consecutive reactions were realized with cetyl alcohol as carrier and an activity of 20% was retained. CONCLUSIONCetyl alcohol was found to be the most appropriate carrier for the immobilization of the investigated laccase, due to easy handling and high yields. In comparison with the other tested carriers, the best retained activities were obtained and recycling of the biocatalyst was realized. (c) 2017 Society of Chemical Industry