Solid phase enzymatic glycerolysis of beef tallow resulting in a high yield of monoglyceride

Abstract

A mixture of mono-, di-and triglycerides was obtained when beef tallow was reacted with glycerol using lipase enzyme as a catalyst. The reaction was carried out batchwise in a small vessel with agitation by magnetic stirring. The yield of monoglyceride (MG) was greatly influenced by the reaction temperature-at higher temperatures (48-50~ a yield of approximately 30% MG was obtained, while at lower temperatures (38-46~ a yield of approximately 70% MG was obtained. /~ sharp transition was Observed between the high and low yield equilibrium states. The temperature at which this transition occurred is called the critical temperature (Tc) and was found to be 46~ in the case of tallow. During the course of the reaction, when approximately 40% MG had been synthesized, the reaction mixture became solid but the reaction continued until approximately 70% MG had been synthesized.A yield of 70% MG also was obtained with tallow at 42~ when a glycerol/tallow mole ratio ranging from 1.5 to 2.5 was used. The free fatty acid content at equilibrium depended on the water concentration in the glycerol phase and varied from 0.5% to 11.0% when the water content ranged from 0.6% to 12.5%. Above 8% water content, the yield of MG was reduced. Of the commercially available lipases that were investigated, lipase from Pseudomonas fluorescens or Chromobacterium vzscosum resulted in the highest yield of MG. KEY WORDS: Beef tallow, glycerolysis, lipase, monoglyceride.Monoglycerides (MG) are an important group of emulsifying agents widely used in the food industry. At present they are produced commercially by the reaction of natural fats and oils with glycerol (glycerolysis) by using an inorganic catalyst at temperatures greater than 220~ (1,2). A yield of MG of approximately 40% is usually obtained. The use of high temperatures results in the formation of dark-colored by-products with an undesirable flavor. Repeated molecular distillation is used to remove impurities and to concentrate the MG. To obtain a product of higher quality and higher yield, and to minimize energy costs, several attempts have been made to synthesize MG at low temperature using lipase enzymes as a catalyst. Enzymatic synthesis by glycerolysis of triglyceride (TG) oils (3,4) or by reaction of free fatty acid (FFA) with glycerol (5) was achieved using either a simple batch system or a membrane bioreactor system, but the yield of MG was low (less than 25%). A microemulsion system incorporating 1,3 specific lipase was recently used to 6) selectively hydrolyze triglyceride at the 1,3 position resulting in 2-MG (6); or (ii) to transesterify acyl groups from triglyceride to glycerol (glycerolysis reaction) (7). This system requires the use of organic solvents and emulsifying agents and therefore is not practical for large scale synthesis.In the present paper, a process is described for the syn-*To whom correspondence should be addressed. thesis of MG from beef tallow by enzymatic glycerolysis with a yield of approximately 70%. The reaction is effective at moderate temperatures ...

Change in glyceride composition of olive pomace oil during enzymatic esterification

“…This might be explained by the possible random binding of FFAs to available glycerol. It has also been reported by previous workers [15,16] that in the enzymatic esterification of glycerol with oleic acid, an excess of glycerol was able to increase MG production.…”

Repeated use of immobilized lipase for monoacylglycerol production by solid‐phase glycerolysis of olive oil

“…Previous studies (8)(9)(10)(11)(12) have demonstrated that solidphase glycerolysis of fats and oils, catalyzed by lipases, may be an advantageous approach for obtaining MAG. In this process, the yield of MAG is greatly influenced by the programmed reaction temperatures (8).…”

Relationship between the Molecular Structures and Emulsification Properties of Edible Oils

“…When 8: 0, 10: 0, and 12: 0 were used as FA, the reaction was done for 10 h, and the procedure was repeated three times, since the incorporation degrees of these FAs were low, as described previously.25) In the final purification by column chromatography, TO was eluted by n-hexane instead of n-hexane-diethyl ether (85: IS, v/v). It was confirmed that highly pure TO was obtained by the analysis of thin-layer chromatography-flame ionization detector by the method of McNeill et al 26 ) Preparation of monoacid-TG molecular species and edible oils. Monoacid-TO molecular species were purified by column chromatography on Florisil using n-hexane--diethyl ether (95: 5, vIv) as the eluting solvent.…”