title: Continuous enzymatic transesterification of sesame oil and a fully hydrogenated fat: effects of reaction conditions on product characteristics.
abstract: An immobilized lipase from Thermomyces lanuginosus (TL IM) was employed to mediate the continuous transesterification of sesame oil and fully hydrogenated soybean oil (FHSBO) in a packed-bed reactor operating at 70 degrees C. Reactions between sesame oil (rich in LLL (15.97%), LOL (31.56%), and OLO (21.15%) [L = linoleic; O = oleic]) and the fully hydrogenated fat ((73.7% SSS, 26.3% SPS) [S = stearic; P = palmitic]) produced semi-solid fats. These products are complex mixtures of triacylglycerol (TAG) species whose compositions depend on reaction conditions. The dependence of the steady state product TAG profile on space time was determined for four initial weight ratios of sesame oil to hydrogenated fat (90:10, 80:20, 70:30, and 60:40). Except for the trial involving a weight ratio of sesame oil to FHSBO of 60:40, near equilibrium conditions were achieved at space times of 30 min-1 h. The chemical, physical, and functional properties of the product semi-solid fats were characterized. The predominant TAG species in the quasi-equilibrium products obtained from the mixture initially containing 90% (w/w) sesame oil and 10% FHSBO were LOL (26.22%) and OLO (21.92%). For transesterification of 80% sesame oil and 20% FHSBO, the major product species were OOP (21.27%), LOL (17.46%), and OLO (13.93%). OOP (24.38%) was the major product for reaction of 70% sesame oil with 30% FHSBO. Appropriate choices of reaction conditions and initial ratios of sesame oil to FHSBO lead to TAG with melting profiles and solid fat contents (SFC) similar to those of a variety of commercial products.
authors.affiliation: Instituto de Catálisis y Petroleoquímica, CSIC, Madrid, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Otero
authors.forename: Arnoldo
authors.initials: A
authors.lastname: López-Hernandez
authors.forename: Hugo S
authors.initials: HS
authors.lastname: García
authors.forename: Estela
authors.initials: E
authors.lastname: Hernández-Martín
authors.forename: Charles G
authors.initials: CG
authors.lastname: Hill
mesh_terms: D001203:Ascomycota / Q000201:enzymology*; D020650:Combinatorial Chemistry Techniques / Q000379:methods*; D004800:Enzymes, Immobilized / Q000737:chemistry; D004951:Esterification; D005227:Fatty Acids / Q000737:chemistry*; D006865:Hydrogenation; D008049:Lipase / Q000737:chemistry*; D012715:Sesame Oil / Q000737:chemistry*; D013024:Soybean Oil / Q000737:chemistry*; D044242:Trans Fatty Acids / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D005227:Fatty Acids; D044242:Trans Fatty Acids; D013024:Soybean Oil; D012715:Sesame Oil; D008049:Lipase