JPS61179299A - Recovery of hard butter from vegetable fat - Google Patents

Abstract

Hard butters for confectionary are obtained by separating mid- and oelin- fractions and preferably also a stearin-fraction, from a vegetable fat containing substantial amounts of symmetrical disaturated triglycerides of C<1><6>/C<1><8> fatty acids and rearranging the gylcerides in a mixture of the olein fraction with a substantially saturated C<1><6>/C<1><8> fat, preferably the stearin fraction, in the presence of a catalyst, preferably a lipase enzyme, which is selectively active in the 1,3-positions only of glycerides, to provide increased amounts of symmetrical disaturated triglycerides which may be fractionated from the rearranged product.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to hard butter and its production from edible fats.

The palatability of chocolate fat and other hard butter compositions containing cocoa butter is
This is mainly attributed to the presence of a high proportion of 2-oleylglycerides of palmitic and stearic acids. The various alternative fats proposed as replacements for this expensive fat likewise contain more or less substantial amounts of these triglycerides. Processes for producing cocoa butter substitutes and extender fats from these alternative sources generally involve a fractionation step in which these more valuable glycerides are separated from other glycerides, particularly those with less desirable melting properties. tri-saturated and mono-saturated and tri-unsaturated triglycerides.

It is also separated from asymmetric disaturated glycerides. Separation is typically accomplished by fractionated crystallization from solvents such as acetone or hexane, among others. The more highly saturated glycerides are removed in the high-melt or stearin fraction and the more highly unsaturated glycerides are removed in the lower-melt or olein fraction.

These less desirable fractions make up half of the initial fat and deserve a much lower premium than the hard putter fraction.

Transesterification of fats and glyceride oils by a method using enzymatic rearrangement catalysts is described in GB 1577933. EP 69599 describes a process for rearranging the glycerin IJ y in the fractions obtained and then fractionating the product if desired to recover a higher degree of symmetrical glycerides, especially for the production of cocoa butter substitute fats. A fractionation method is disclosed.

The present invention provides a method for recovering hard butter from vegetable fats.

In this process, a vegetable fat containing a substantial amount of symmetrically disaturated triglycerides of 016 and 018 fatty acids is fractionated to recover this glyceride by separating at least a more highly unsaturated, low-melting olein fraction; , preferably substantially saturated by recombining with a high-melting stearin fraction separated from vegetable fats (C16/C1e) liglyceride fat, the mixture preferably only in the outer positions of the glycerides, i.e. one of the glycerides - and transesterification in the presence of an enzyme catalyst selectively active at the 3- or alpha-positions to yield more symmetrical disaturated glycerides.

Since the largest proportion of the olein fraction consists of glycerides with unsaturated fatty acid residues in the 2-position, it is theoretically possible to convert all of these into symmetric disaturated triglycerides by transesterification under the action of enzyme catalysts. be. However, in the admixture, e.g. in the high-melt or stearinic fractions that are combined, saturated fatty acid residues may be present in the alpha or 6-positions which are susceptible to catalysis in order to carry out the transesterification with the more highly unsaturated glycerides. The only condition is that there is sufficient glyceride containing. For example, trisaturated glycerides are transesterified with tri-unsaturated glycerides to provide 1-saturated tri-unsaturated glycerides, which in turn become 3-disaturated glycerides under the action of the selective activity of the catalyst. The trisaturated glycerides themselves are converted correspondingly into asymmetric di-saturated monounsaturated glycerides p and symmetric di-unsaturated glycerides, ie 6-di-unsaturated, 2-saturated glycerides.

The transesterified glycerides can be separated as in conventional fractionation methods to recover a fraction consisting essentially of symmetrical disaturated glycerides for use as a cocoa butter substitute fat. In particular, the more highly unsaturated glycerides in the transesterification mixture containing symmetric, 3-di-unsaturated glycerides form a low-melting olein fraction.

Any unreacted trisaturated glycerides can be separated into a top fraction if necessary and recycled for further transesterification with any unsymmetrical disaturated glycerides. These appear in either the stearin or olein fractions separated from the symmetric disaturated fractions.

The transesterified glyceride mixture can be separately fractionated or recombined with the raw fat in the fractionation step of the process.

In continuous operation, where the feedstock is introduced into a circulation through a fractionation and transesterification unit and the symmetrical disaturated glyceride fraction is removed from this circulation, the feedstock is introduced into either unit to form the cold transesterification product. It can be mixed and initially fractionated, or it can be first transesterified with the recycled transesterified fraction from which the symmetrical disaturated glycerides are removed. In continuous operations where feedstock fats and oils are introduced and the symmetric di-saturated fraction is removed, purification of the symmetric di-unsaturated glycerides is necessary to avoid the formation of this recalcitrant material in the recycle composition. Rearrangement catalysts, such as non-selective catalysts, 2-selective catalysts, or catalysts that are selectively active for saturated fatty acid residues but not for unsaturated fatty acid residues, convert and further process this material. It can also be used to return it to a more convenient shape. A particular advantage of continuous operation is that the transesterification requires a relatively short time and transesterification does not have to be sufficient for each pass through the unit. Enzymatic transesterification is generally substantially slower than transesterification under the action of the inorganic catalysts used in Takagata. However, by continuous recirculation, the residence time of the transesterification step is sufficient to provide a significant improvement in the yield of the desired glyceride even if equilibrium is not necessarily reached.

The present invention provides a fat that can be used in margarine or other emulsions, edible streak reds, or ice creams, without fractionation or recirculation, especially for the production of hard stock fats which are then blended with liquid glyceride oils. including recovering the product from the rearrangement step.

The fractionation step carried out according to the invention comprises an acceptable solvent,
Any solvent fractionation using e.g. acetone, hexane or nitroparaffin or an environmental gas in pressurized liquid state.
This is a common practice.

Fractionation is at least a partially solvent-free drying method;
The separation of liquid and solid phases during the fractionation can then be facilitated by the use of aqueous surfactant dispersions, as in the so-called Lande process.

Preferably, however, the fractionation is carried out in acetone at a temperature of 15 to -5°C or in hexane at a temperature of 10 to -20°C.

Contains transesterified mucor mlehei only at the outer position of the glyceride molecule. These enzyme catalysts leave unsaturated fatty acid residues at the 2-position of the low-melting fraction glycerides unaltered by transesterification, providing the basis for the preparation of the desired symmetrical disaturated glycerides in the reaction of the intermediate fractions. Guarantee. Although enzymatic catalysts are particularly preferred for this method, other catalysts can of course be employed provided that they exhibit selective activity only in the alpha position. The transesterification reaction is carried out in a solvent inert to the catalyst, in particular hexane for enzyme catalysts, or without a solvent; the reaction is carried out batchwise or continuously; in the latter case the catalyst is preferably immobilized in the reaction vessel; Through this vessel a reaction mixture containing high-melting and low-melting mixed fractions is passed.
den) passes. The enzyme catalyst can be preactivated by contact with water and supported on a suitable support as described in Applicant's GB 1577933.

Water content is controlled by humectants and/or humectants to remove water from the reaction phase.
or by other means up to the predetermined limits in accordance with the applicant's patent specifications (UK patent abandoned, but IP64855). The water content is preferably no more than 2 g, especially no more than 1 g of the reaction mass containing the solvent.

In particular, the water activity AV is preferably less than 5% during the reaction. However, enzyme catalysts can be used in polyhydric alcohol solutions to maintain very low water content. Preferably, the water content is low enough to minimize the extent of hydrolysis that occurs with the formation of partial glycerides.

However, these can be removed by selective adsorption means using silica-type adsorbents.

Suitable fats include in particular palm oil, but shea, sal, pentadesma oils and, of course, fluorobacter itself can all be processed according to the invention.

Vegetable oils and fats are used because they contain many unsaturated fatty acid residues in the 2-position of their glycerides. Mixtures of fats and oils can be used, and fats lacking trisaturated glycerides can be mixed with other fats containing these or hydrogenated to provide sufficient amounts for the transesterification reaction. It is preferable to refine the oil before use as the raw material fat for the present invention, and both neutralized and unneutralized fats and oils can be used.

Example: Equal weight parts of olein and stearin fractions obtained by removing the palm intermediate fraction by acetic fractionation of palm oil were combined, the mixture was dissolved in 6 times the weight of hexane, and Mucor minihei derived from microorganisms was used as a transesterification catalyst. The mixture was transesterified using a 1,3-specific enzyme supported on diatomaceous earth in a packed bed reactor and activated with water before use. Micella containing 500 ppm water was transesterified at 6 nozzles per hour. It was fed through a reactor containing .7 kl of catalyst.

The residence time in the reactor was approximately 30 minutes and the reaction was conducted at 55°C.

The solvent was evaporated from the product, then first at 20°C and then at 5°C.
Intermediate fractions were collected by recrystallization from acetone at °C. This was compared in the table with a sample of the intermediate fraction obtained by crystallization from unmodified palm oil.

The composition of the raw oil/fat mixture and its components are also shown in the table.

The oleic and stearin fractions derived from the reaction products were found to be essentially the same in composition. Triglyceride analysis is determined using a silver-phase HPLC method.

Table A Tomo Notaku Kakero Kuze Jun 4'iy75"" 0 12.3 4.910-9
,45.127.0n top fraction 77.41B,2 2.6 ,4
0.4 0 mixture 42.015.9 3.7
5.520.712.3 Product 22.822.
625.0 7.620.11, intermediate from 8 products
4.343.73, 2 6.21L4 3.2 Fraction

Claims (1)

[Claims] A vegetable fat containing a substantial amount of symmetrically disaturated triglycerides of C_1_6/C_1_8 fatty acids is fractionated and crystallized to recover this glyceride and more highly unsaturated olein fraction, which olein fraction is then converted into the vegetable fat,
In a process for recovering hard butter from vegetable fats, preferably from palm oil, preferably by mixing with a substantially saturated glyceride composition recovered by fractionation, the mixture thus obtained is combined with a transesterification catalyst, preferably one of the glycerides. transesterification in the presence of selectively active lipase enzymes only in the - and 3-positions, the rearranged glyceride products are preferably fractionated, and the symmetrical disaturated triglycerides are preferably recovered in a continuous process comprising fractionation and transesterification steps. However, the reactants are circulated between these steps, the raw oil containing this vegetable fat is introduced therein, the symmetrical disaturated glyceride fraction is recovered therefrom, and if necessary any of the fractionation and/or transesterification steps are carried out. The above method, characterized in that a solvent is used.