Process for the preparation of a monoglyceride

Details Process for the preparation of a monoglyceride Process for the preparation of a monoglyceride

2001-02-28

2002-12-31

Carr, Deborah D. (Department: 1621)

Organic compounds -- part of the class 532-570 series

Organic compounds

Fatty compounds having an acid moiety which contains the...

Reexamination Certificate

active

06500974

ABSTRACT:

FIELD OF THE INVENTION
The present invention relates to a process for the preparation of a monoglyceride. The present invention particularly relates to a catalyst free improved process for the preparation of a monoglyceride by reaction of fatty acids with glycerol in the presence of solvent, under conditions that favour the predominant formation of monoglycerides.
BACKGROUND OF THE INVENTION
Monoglycerides constitute an important group of commercial derivatives which are used in food, cosmetic, pharmaceutical, lubricant and chemical industries. Monoglycerides find many applications as surfactants, mainly as emulsifiers, in a wide range of foods, cosmetics and pharmaceuticals. Monoglycerides are used in yeast-raised foods for retarding staling, cakes, icings and in the manufacture of margarine. Overall, this group of surfactants is the single most important one for food uses, representing about 75% of total emulsifier production. (
Bailey's Industrial Oil Fat Products,
Vol. 3, 5
th
Edition;
J. Am. Oil. Chem. Soc.,
1976, 53, 400;
J. Am. Oil. Chem. Soc.,
1984, 61, 255;
Angew. Chem. Int. Ed.,
1988, 27, 42). Surfactants have a wide field of application in all those processes that involve working with interfaces. Nonionic surfactants especially esters of hydrophillic polyols, such as glycerine with fatty acids are of great interest (Falbe, J.,
Surfactants in Consumer Products: Theory, Technology and Applications,
Springer-Verger New York, 1988). The most important commercial products are glycerol monostearate, monooleate, and monoricinoleate. Owing to their ability to form stable emulsions, monoglycerides such as monooleates are suitable as emulsifying components in aqueous fiber finishes, lubricant components, fine mechanical oils, water displacing oils and in grinding and polishing pastes (
J. Am. Oil. Chem. Soc.,
1984, 61, 255). Monoglycerides are also reported to possess antibacterial properties. (Kabara, J. J.,
The Pharmacological Effect of Lipids,
2
nd
Edition, The American Oil Chemist's Society, Illinois, 1985). Recent developments include their use as drug delivery facilitators and bioadhesives (
Int. J. Pharma,
1997, 147, 135;
Biomaterials,
1997, 18, 63). They are reported to have a preventive effect on cardiovascular diseases. (
J. Am. Oil. Chem. Soc.,
1993, 70, 745).
Many methods are described in prior art for the preparation of monoglycerides. Commercial manufacture of monoglycerides involves either glycerolysis of oils and fats at high temperature or direct esterification of fatty acids and glycerol with or without catalysts. Various types of homogenous and heterogenous catalysts are reported (
J. Am. Oil. Chem. Soc.,
1976, 53, 400;
J. Am .Oil Chem. Soc.,
1982, 59, 795A;
Nature,
1960, 188, 56;
J. Am. Oil. Chem. Soc.,
1962, 39, 345;
J. Am. Oil. Chem. Soc.,
1964, 41, 727;
Chem Rev,
1958, 58, 845;
J. Am .Oil. Chem. Soc.,
1966, 43, 536;
J. Org. Chem.
1997, 62, 749;
J. Am. Oil. Chem. Soc.,
1998, 75, 755). In all these processes the yields are typically in the range of 50%. Pure monoglycerides (over 90%) are obtained by molecular distillation which sometimes is a part of industrial process (
Fette. Seifen. Anstrichmittel,
1983, 85, 443;
Chem Abstr
1995, 123, 202772c).
Feuge and Gross (
J. Am. Oil. Chem. Soc.,
1950, 27, 117) described preparation and purification of technical monoglycerides by modification of vegetable oils. They carried out reaction between fat and glycerol under hydrogen at atmospheric pressure using a glass vessel equipped with a stainless steel stirrer at 200-250° C. Monoglycerides to an extent of 40 and 60% were obtained by using approximately 20 and 45% glycerol respectively with sodium hydroxide as catalyst. Higher yields of monoglycerides are reported with soaps of iron, nickel, chromium or manganese as catalysts (U.S. Pat. No. 2,628,967). Choudhury reported glycerolysis of various oils for the preparation of monoglycerides and found that the maximum amount of monoglyceride formed by glycerolysis was about 45% (
J. Am. Oil. Chem. Soc.,
1960, 37, 483).
A commercial non-solvent method of production involving glycerolysis of hydrogenated cottonseed oil with 40% glycerol (based upon the weight of fat used) at 250° C. yields about 60% of monoglycerides (
J. Am. Oil. Chem. Soc.,
1979, 56, 752A). Castor oil glycerolysis was claimed to give 82% alpha-monoglycerides after 2 hours at 240° C. with 800 gm of oil and 2000 gm of glycerol, in the presence of carbon dioxide at 100 psi as a coblanketing catalytic agent. Under similar conditions coconut oil gave 74 and peanut oil 73% of monoglyceride. (Indian patent 71,979).
Recently glycerolysis of methyl stearate and tristearin has been carried out in the presence of alkyl guanidines, strong non-ionic bases as catalyst. The reaction was carried out at 10 mol % of 1,5,7-tri-azabicyclo(4.4.0)de-5-ene, 1,2,3-tricyclohexylguanidine or 1,3-decyclohexyl-2-n-octylguanidine resulting in monoglycerides in more than 90% selectivity at 50% conversion at 110° C. and 16 mbar pressure. They found that a higher conversion of about 80% resulted in lower selectivity (50-60%) for monoglycerides (
J. Am. Oil. Chem. Soc.,
1998, 75, 755).
Choudhury also studied direct esterification of fatty acids with glycerol for preparation of monoglycerides in optimum yield and carried out reactions with excess glycerol at 180° C. in the presence or absence of alkaline catalysts and reported a maximum yield of 55-60% of monoglyceride (
J. Am. Oil. Chem. Soc.,
1960, 37, 483). Selective esterification of glycerine to glycerol monooleate using a slightly basic ultrastable Y-Zeolite as catalyst was reported to give monoglycerides with a selectivity of about 90% (
Ind. Eng. Chem. Res.,
1997, 36, 1524). Esterification of oleic acid with glycerol in the presence of superacidic sulfated iron oxide catalyst was reported (
J. Am. Oil. Chem. Soc.,
1996, 73, 347). Monoglycerides were also obtained by esterification reaction over an acid catalyst. High pressure and temperatures were used to shift the equilibrium forward towards monoglyceride production. The product obtained was a complex mixture of 35-60% monoglyceride, 35-50% diglyceride, 1-20% triglyceride, 1-10% glycerine and fatty acids. The amount of monoglyceride was raised to 90-95% with 7-10% of 2-monoglyceride by molecular distillation. The advantage of pressure in carrying out glycerolysis is noteworthy. It appears to aid in the attainment of homogeneity and thus yields were improved.
Although the yields of monoglycerides by usual non-solvent methods of production are limited to about 60% of total glycerides, the use of solvents for the glycerolysis reaction enables a much higher conversion. Immiscibility of glycerol in fat like phases was overcome by carrying out the reaction in a solvent medium. Solvents like phenol, cresols, 1,4 dioxane, pyridine, chloroform and dimethyl formamide etc were used (
J. Am. Oil. Chem. Soc.,
1982, 59, 795A;
Fat. Sci. Technol.,
1995, 97, 347;
Chem Abst,
1990, 112, 197639a,). Solvents offer the prospects of high yields at relatively low temperature but disadvantages in their handling, toxicity, noxious odors etc and the need to remove them completely from products explains the very limited efforts directed towards the synthesis in solvents. For example, Sunflower oil 10 parts, was reacted with glycerol, 20 parts at 120° C. with 0.3 parts of sodium bicarbonate in excess pyridine yielding 83% of total monoglycerides containing about 8% of 2-monoglyceride. In the absence of solvent, the reaction yielded 58% total monoglyceride containing 6% of beta-monoglyceride (
J. Am. Oil. Chem. Soc.,
1979, 56, 751A). Kinetics of esterification reaction between glycerol and oleic acid in the presence of pyridine for production of partial glycerides was studied (
Fat. Sci. Technol,
1995, 97, 347). The authors found pyridine to be a good solvent for the formation of partial glycerides.
The use of enzymes for the synthesis of MG was extensively studied (
Enzyme Microb. Technol.,
1995, 17, 578;
J. Am. Chem. Soc.,
1999, 76, 701). U.

Affiliated with

Also associated with

Rating

Process for the preparation of a monoglyceride does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Process for the preparation of a monoglyceride, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the preparation of a monoglyceride will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2971414