Heterogeneous biocatalyst: Polyurethane foam coating technique with co-immobilized lipase for bio-flavor production

Abstract

Bio-flavor is produced from the esterification reaction including free fatty acids and citronellol. Free fatty acids (lauric C12) can be obtained from the hydrolysis of coconut oil substrate. Both of these reactions use heterogeneous polyurethane foam (PUF) matrix catalysts which immobilize the lipase enzyme. PUF is used as an immobilized matrix, because it has characteristics as open cell, rigid, high porosity, consists of of the ether-, carbamate-, amide-groups, so it has the ability to absorb water-oil. PUF has been modified its surface structure by co-immobilized lipase coating technique to make it more hydrophobic/oleofilic. Co immobilized consists of a mixture of gelatine, lechitin, polyethylene glycol (PEG), MgCl2. The aim of this research is to compare the immobilization technique of lipase Mucor miehei using different carriers, that are zeolite, alginate and polyurethane foam (PUF) to produce bio-flavor at mild condition. Each of that was through the mechanism of adsorption, entrapment and covalent binding process. The research was done in specific condition and all of the carriers has gone through the esterification process using different mole ratio of FFA and citronellol. Optimum result of bio-flavor conversion was obtained at the temperature of 40°C, highest thermal stability of 90% and the ability for reusage 4 times on PUF carrier. This results have proven to be cheaper on cost and environmentally friendly.