Premium
Increased rate of lipase‐catalyzed saccharide‐fatty acid esterification by control of reaction medium
Author(s) -
Zhang Xun,
Hayes Douglas G.
Publication year - 1999
Publication title -
journal of the american oil chemists' society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.512
H-Index - 117
eISSN - 1558-9331
pISSN - 0003-021X
DOI - 10.1007/s11746-999-0191-3
Subject(s) - oleic acid , chemistry , fructose , catalysis , lipase , reaction rate , butanol , fatty acid , glycerol , solvent , chromatography , organic chemistry , nuclear chemistry , ethanol , biochemistry , enzyme
Through proper selection of initial conditions and control of the reaction medium composition, a productivity rate over 10‐fold higher than that previously reported was achieved for lipase‐catalyzed fructose‐oleic acid esterification. From a screening process, tert ‐butanol ( t ‐BuOH) was selected as the most effective solvent for cosolubilizing fructose and oleic acid during the initial stage of the reaction. A t ‐BuOH concentration of 0.35–0.55 w/w produced the highest rate and extent of reaction at 60°C. Neither water addition nor removal applied to initial reaction materials improved the rate. Since both fructose‐oleic acid mono‐ and diester promoted higher fructose solubility than either oleic acid or oleic acid/ t ‐BuOH mixtures, t ‐BuOH was not needed during the latter stage of the reaction. Also, the presence of t ‐BuOH hindered the removal of water by free evaporation. Thus, complete removal of t ‐BuOH during the middle‐to‐latter stage of reaction was found to enhance the reaction rate. In addition, the introduction of fructose to the reactor in small batchwise increments accelerated the reaction. The monoester to diester ratio decreased during the initial and middle stages of the reaction owing to the disappearance of t ‐BuOH, but increased slightly during the later stages presumably because of the ester formation.