Organic compounds -- part of the class 532-570 series – Organic compounds – Fatty compounds having an acid moiety which contains the...
Reexamination Certificate
2001-01-08
2002-01-08
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...
C435S134000
Reexamination Certificate
active
06337414
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a preparation process of partial glycerides making good use of a glycerolysis reaction of oil or fat by a lipase.
BACKGROUND ART
Preparation processes of partial glycerides include an esterification process and a glycerolysis process, and each process includes cases making use of a chemical catalyst and cases making use of an enzyme catalyst. As an esterification process making use of an enzyme catalyst, there has been known a process in which partial glycerides are prepared from oleic acid or the like high in fatty acid purity and glycerol as described in Japanese Patent Publication No. 56311/1994 and Japanese Patent Application Laid-Open No. 19090/1987. However, this process is not preferable as the preparation process of the partial glycerides from the economical point of view because a fatty acid prepared by decomposing oil or fat at a high temperature and a high pressure and then removing a colored component by a distilling treatment is used, and glycerol obtained by dehydration, concentration of purification treatments of an about 10% aqueous solution of glycerol produced upon the decomposition of the oil or fat is used. Accordingly, the glycerolysis process in which both fatty acid group and glycerol group constituting the partial glycerides are derived from a cheap oil or fat, and a deficient glycerol group can be supplied as glycerol is effective as the industrial production process of the partial glycerides.
The processes for preparing the partial glycerides from such a cheap oil or fat and glycerol by an enzymatic glycerolysis reaction are reported in Japanese Patent Publication No. 12710/1992, JAOCS, 71, 3, 339 (1994), etc.
However, the process described in Japanese Patent Publication No. 12710/1992 requires a special lipase satisfying conditions under which no secondary production of free fatty acids in a low water content region is attendant, so that it is difficult to preset a water content in a reaction system and procure the lipase. On the other hand, in the process described in JAOCS, 71, 3, 339 (1994), the partial glycerides are prepared from hydrogenated hardened beef tallow and glycerol by a glycerolysis process by which the formation of fatty acids is inhibited. However, this process has involved a problem that reproducibility of the reaction is poor.
Accordingly, it is an object of the present invention to provide a process for preparing a partial glyceride with industrial advantage by an enzymatic glycerolysis reaction.
DISCLOSURE OF THE INVENTION
The present inventors have found that when in a glycerolysis reaction of oil or fat making use of an easily available lipase, the reaction is conducted in a system in which water is present, under conditions that the secondary production of fatty acids occurs to a great extent and that crystals are precipitated in the reaction system, which are entirely different from the usual common sense, the yield of a partial glyceride, particularly a diglyceride is enhanced with great strides, thus leading to completion of the present invention.
According to the present invention, there is thus provided a process for preparing a partial glyceride, which comprises, in a glycerolysis reaction of oil or fat making use of a lipase, conducting the reaction in the presence of water under conditions that crystals are partially precipitated in the reaction system in the course of the reaction and the concentration of free fatty acids in an oil phase amounts to at least 5% by weight.
According to the present invention, there is also provided a process for preparing a diglyceride, which comprises conducting a removing operation of fatty acid, glycerol and monoglyceride components from a reaction mixture in the reaction described above or after completion of the reaction.
BEST MODE FOR CARRYING OUT THE INVENTION
In the present invention, oil or fat, a lipase, glycerol and water are used as raw materials. Examples of the oil or fat include vegetable oils and animal oils, more specifically, soybean oil, rapeseed oil, cotton-seed oil, corn oil, rice oil and fish oil. Oil or fat, in which a proportion of saturated fatty acids in the acyl group is at most 30% by weight, is preferably used. When the content of the saturated fatty acids is high, not only a high temperature is required of the reaction, but also a reaction product cannot be taken out of a vessel after the reaction, or heating is required, and so handling is complicated because the melting point of the raw oil or fat itself is high and the melting point of a partial glyceride formed is higher. In addition, a problem of deactivation of the enzyme arises in the high-temperature and high-water content system.
No particular limitation is imposed on the lipase used. However, an enzyme (1,3-position-selective lipase”) specifically acting on the 1- and 3-positions of glycerol is preferred. More preferably, lipases derived from microorganisms of the genera Rhizopus, Aspergillus and Mucor, and splenic lipases, more specifically, lipases derived from
Rhizopus delemar, Rhizopus japonicus, Rhizopus niveus, Aspergillus niger, Mucor javanicus
and
Mucor miehei
may be used. Immobilized lipases obtained by immobilizing each of the lipases on various kinds of carriers (Celite, diatomaceous earth, silica gel, ion-exchange resin, etc.) may also be used. In general, the use of the latter lipases, i.e., (heat-resistant) immobilized lipases having high durability in a wide concentration range is preferred to the use of the former lipases. Many of these lipases or immobilized lipases are easily available as products on the market. The amount of the lipase used is preferably 0.1 to 30% by weight, particularly 1 to 15% by weight (200 to 100,000 units per g of oil or fat) based on the raw materials for the reaction.
No particular limitation is imposed on the water content in the process according to the present invention. However, it is preferably 5 to 50% by weight, particularly 8 to 30% by weight, in terms of an initial concentration in the reaction system, based on glycerol from the viewpoint of acceleration of the reaction. With the progress of the reaction, the water content in the reaction system somewhat varies. However, the reaction is scarcely affected thereby.
Fatty acids and partial glycerides may exist in the raw materials for the reaction in addition to the oil or fat, glycerol and water. However, the number of moles of glycerol group is preferably controlled to a range of 0.3 to 3, particularly 0.8 to 1.5 per mole of the fatty acid group in the whole raw material.
The reaction conditions in the present invention require that crystals are partially precipitated in the reaction system in the course of the reaction and the concentration of free fatty acids in an oil phase amounts to at least 5% by weight. The conditions under which crystals are partially precipitated in the reaction system in the course of the reaction are conditions that oil or fat to be reacted is naturally melted in the initial stage of the reaction, but parts of monoglycerides and free fatty acids formed with the progress of the reaction are precipitated.
Thus, it is assumed that both of monoglycerides and free acids are partly excluded from the phase system of the reaction when brought in the condition under which a part of crystals is precipitated in the course of the reaction, whereby the glycerolysis reaction is further accelerated. Such conditions vary according to the oil or fat used as a raw material. When oil or fat, in which a proportion of saturated fatty acids in the acyl group is at most 30% by weight, is used as the oil or fat, the conditions are preferably achieved by presetting the reaction temperature to a range of 0 to 250° C., particularly 0 to 150° C.
In the present invention, the conditions are preset in such a manner that the concentration of free fatty acids in an oil phase amounts to at least 5% by weight, preferably 8 to 30% by weight, the yield of the partial glycerides is enhanced with great strides. Such conditions are preferably achieved b
Maruyama Eizo
Mine Kouji
Shimizu Masami
Sugiura Masakatsu
Yamada Naoto
Carr Deborah D.
Kao Corporation
LandOfFree
Process for producing partial glyceride 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 producing partial glyceride, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for producing partial glyceride will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2862717