JPH0430836B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a process for the production of edible fats and fats for use in confectionery, including tyokolate, shortening, margarine and other plastic emulsion spreads. The improvement of edible fats and oils by rearranging the fatty acid residues of their constituent glycerides has been practiced in the food industry for many years. According to US Pat. No. 2,928,745, assigned to River Brothers, hydrogenated palm kernel oil is randomized using the rearrangement catalyst sodium methoxide and then fractionated to obtain hard fat for confectionery. Proposals have also been made to synthesize triglycerides. According to US Pat. No. 3,012,890, mono- and di-glycerides of fatty acids are reacted with acid chlorides to obtain synthetic triglycerides. Recently, a lipase-containing catalytic rearrangement and synthesis method was proposed. A particularly interesting proposal is the use of selectively active oxygen, which is effective in the 1- and 3-positions of the glyceride, without affecting the 2-position. US Patent No.
No. 4,275,081 describes a rearrangement process under the influence of a lipase rearrangement catalyst activated with a small amount of water. Using this technique, unsaturated vegetable fat oils such as sunflower oil can be converted into symmetrical disaturated triglycerides of saturated fatty acids themselves or their alkyl esters, especially palmitic and stearic acids, which can be used to convert cocoa butter and other Its presence in vegetable fats is responsible for the sharp melting properties and other physical contributions that make these expensive and often scarce products so highly prized. The best of these glycerides are 2-
It is an oleoyl homologue. The corresponding 2-linoleoyl and linoleoyl disaturated triglycerides exhibit somewhat less satisfactory properties. Furthermore, high unsaturation makes it significantly softer and more susceptible to oxidative deterioration. Their conversion to monoolefinic unsaturation by selective hydrogenation has a high degree of simultaneous conversion by isomerization to elaidic acid, i.e. the trans form of oleic acid, thereby converting the corresponding 2- The introduction of more highly soluble triglycerides than oleoyl isomers into glyceride compositions is a less than satisfactory solution. Furthermore, highly melting 2-elidoyl disaturated triglycerides exhibit immiscibility with pre-existing triglycerides. This results in unusual and undesirable melting behavior. Furthermore, the by-products of all rearrangement processes of highly unsaturated glyceride oils that are separated from the more saturated products are themselves highly unsaturated and likewise unstable and susceptible to ambient oxidation. Although they can hydrogenate saturated fatty acids or their derivatives, significant amounts of hydrogen are consumed in the process to be recycled to the rearrangement process. Therefore, the presence of substantial amounts of 2-linoleoyl and 2-linoleoyl triglycerides in many vegetable oils, including sunflower oil, makes it a suitable 1,3-specific rearrangement method for use in thiokolate and confectionery. would limit its value in The present invention provides a reordering method that appropriately and economically solves this drawback. The present invention provides a method for producing edible fats suitable for use in confectionery and similar edible compositions, wherein unsaturated glyceride fats are produced by contacting with lipase as a rearrangement enzyme in the presence of saturated fatty acids or esters thereof. It further rearranges to a higher degree of fat, the fat having a high oleate content and desirably consisting essentially of 2-saturated triglycerides, at least 90% of which are 2-oleoyl triglycerides. The present invention also provides C ₁₆ and
Also provided are novel fats containing symmetrical disaturated triglycerides of _C18 fatty acids. Such fats are obtained by the rearrangement method of the present invention using 1,3-specific lipase as rearrangement agent, as described in US Pat. No. 4,275,081. Useful commercially available high oleic sunflower seeds suitable for use in the present invention include, for example, naturally occurring high oleic sunflower seeds (Horwits and Winter, Nature, 179:582, 1975).
It can be obtained by the conventional plant compounding technique of crossing. High oleic mutants produced by artificial methods such as seed mutation treatments can also be used and are suitable for Pervenets species (Kharachenk, Fisiologiya Rastenii 26:1226,
1979) is an example. Progeny derived from such mutants are known as reported by Fick.
Preferably, as sunflower seeds, an oil having less than 10% linoleic acid, for example 3%, especially the AOCS method.
for at least 100 hours as measured by Cd12−57
Plant species that have an AOM value (active oxygen method) are used. Other oils suitable for use in the present invention include selected olive oils, sheer olein, salolein, cottonseed olein and wintered cottonseed oil. The enzyme rearrangement process of the present invention is carried out in a substantially non-aqueous and essentially water-immiscible liquid phase. Even so, a small amount of water is initially required to activate the enzyme. This can be done by first contacting the enzyme with water or, in a batch process, by including a small amount of water in the raw material. To increase catalyst activity, a balance is required since more water is provided to speed up the reaction rate, increasing the tendency for reactants and products to hydrolyze (as the rearrangement process is reversible). Therefore, we set the water activity of the system to 0.2
It is preferable to keep it at ~0.6. In the continuous process of the present invention in which the reactants are passed through a fixed bed of supported lipase, the water activity of the system is maintained within these limits by including a small amount of water in the feed fed to the fixed bed catalyst. is desirable. With this method, the rearrangement reaction is substantially completed within 2 hours of contact time, and
It is best to maintain water activity at a level that minimizes the effects of isomerization of partial glyceride by-products to produce 2-saturated triglyceride products, using 1,3-specific catalysts to produce symmetrically disaturated 2-triglyceride products. −
Produces oleoyl triglyceride. The rearrangement reaction can be carried out in the presence of a water-immiscible non-polar solvent such as hexane or other hydrocarbon to maintain the reactants in the liquid phase. If a solvent is used, the concentration of reactants in the solvent is preferably 20-50% by weight. The reaction is carried out at a slightly elevated temperature, e.g. 40 DEG -80 DEG C., at which temperature the selected catalyst remains active and the reactants are generally in the liquid phase. The catalyst may be, for example, an inert carrier such as celite or other particulate silicic acid, an inert inorganic carrier or an ion exchange medium,
It is preferable to support it on an organic material such as a resin or an inorganic material such as zeolite. The amount of lipase is 0.01~ of the carrier
0.1% by weight is good; commercially available lipase contains about 1%
A sufficient amount of the commercially available product is used to achieve this concentration of lipase in the carrier. Suitable 1,3-specific enzymes include Mucor
miehei, Rhizopus.A.niger and Aspergillus. The acidolysis reactants used in conjunction with sunflower or other oils according to the invention may be in the form of free saturated fatty acids, preferably palmitic acid, stearic acid or mixtures thereof. Alternatively, it may desirably be present as an ester of a short chain saturated monohydric alcohol, such as the methyl or ethyl ester of palmitic acid or stearic acid. It is desirable to use 1 to 5 moles of acylidolysis reactant per mole of oil, more preferably 3 to 5 moles. The rearranged triglyceride products of the present invention are preferably recovered from the reaction mixture by fractional crystallization at a temperature of preferably 10 to 40°C, after first fractionating any free fatty acids and the solvent used; Or the ester by-product is liquid and can be separated from the crystalline product. Fractionation can be carried out using a suitable solvent such as acetone. Alternatively, these by-products can be removed under reduced pressure by conventional acid purification methods. The by-product can be hydrogenated to the corresponding stearic acid or ester thereof and reused as the acidolysis reactant. Example 1 Equal parts of a mixture of high oleic sunflower oil and stearic acid were dissolved in twice its height in hexane. Half of the resulting feed was saturated with water by passing through a column containing a wet silica gel bed and then combined with the other half. The combined raw materials were transferred to a reaction column containing 1 Kg of transesterification catalyst consisting of Mucor miehei lipase/celite supported prepared as described in GB 1577933 and pre-activated with 10% water before use. The mixture was pumped at a flow rate of 6 Kg/hour at 50°C. The retention time was approximately 15 minutes. After evaporating off the solvent, the free fatty acids were separated using a falling film evaporator and the reaction products were fractionated at −5°C in acetone using a solvent/oil ratio of 5:1 in a scraped surface heat exchanger and stored in Stost. A rich stearin fraction was collected. Table 1 shows the product, stearin fraction and olein fraction data, and compares it to the composition of commercially available shea stearin.

TABLE The substantially high SOS content and low content of SLnS of the stearin fraction is evident from Table 1. Enzymes and shea stearin were evaluated for confectionery fats and oils in equal parts combinations of single and intermediate fractions using the Diensen cooling curve measurement method shown in Table 2.

Table: Oxygenically produced stearin exhibited excellent confectionery fat properties and was similar to shea stearin. Example 2 Example 1 was repeated using the oleic byproduct recovered from Example 1 as the feedstock. The catalyst in this case was supported on a phenol/formaldehyde weak anion exchange resin. In this example, the deacidified product was first fractionated in acetone at 0° C. in a 5:1 solvent/oil ratio to obtain the olein fraction in 56% yield. The remaining stearin fraction was redispersed in acetone in a 3:1 ratio and fractionated in a second stearin fraction at 25°C with an overall yield of 10%, consisting essentially of saturated glycerides and the remaining intermediate fraction in the solvent. Overall yield 34% from
It was recovered. The saturated glycerides in the upper stearin fraction are due to the presence of partial glycerides in the recycled olein that undergoes isomerization followed by transesterification in the reactor. The properties of the product are shown in Tables 1 and 2 and are compared with commercially available shea stearin. Example 3 A reaction mixture of high oleate sunflower oil (2.5 parts by weight) and myristic acid (1.0 parts by weight) dissolved in petroleum ether (8 parts by weight) at 100-120°C was mixed with acid-washed celite (4.0 g) containing 80% by weight of water. ) 40 through the floor
Saturated with water at °C. The water saturated reaction mixture is
A bed of catalyst (2.0 g) consisting of Rhizopus japonicus lipase/Celite at 40°C with a flow rate of 15 mlhr ^-1
I pumped it in. The catalyst prepared as in GB 1577933 contained 1700 lipase units/g and was activated with 10% water before use. The average retention time of the reaction mixture in the catalyst bed was about 15 minutes. The transesterification product contained 58% triglycerides, 6% diglycerides and 36% free fatty acids. Isolate the triglyceride fraction,
analyzed. The results shown in Table 3 show that myristate was added to sunflower oil triglycerides and useful SOS triglycerides were produced. Example 4 A mixture of high oleate sunflower oil (2.5 parts by weight) and methyl palmitate (2.4 parts by weight) dissolved in 100-120° petroleum ether (8 parts by weight) is
The reaction was carried out as described in Example 3 using a catalyst bed of Rhizopus niveus lipase/Celite and a flow rate of 4 mlhr ^-1 . The catalyst contained 1500 lipase units/g. The average retention time of the reaction mixture in the catalyst bed was about 1 hour. The reaction product contained 50% triglycerides, 4% diglycerides, 43% methyl esters and 3% free fatty acids. Analysis of the triglyceride fraction shows that extensive transesterification occurs. Palmitate was added to sunflower oil triglycerides to produce useful SOS triglycerides (Table 1).

【table】

[Table] The above results show that the enzymatically prepared intermediate fraction is similar to shea stearin.

Claims (1)

[Scope of Claims] 1. Confectionery and confectionery foods by rearranging unsaturated glyceride fats and oils in the presence of saturated fatty acids or their esters under the influence of a rearrangement catalyst consisting of a supported lipase enzyme in a fixed bed. A method of producing a food fat suitable for use in a composition, comprising:
The oil has a high oleate content and substantially 2
- consists of unsaturated triglycerides, at least 80% of which are 2-oleoyl triglycerides;
On the other hand, a method in which the water activity of the reaction mixture is maintained between 0.2 and 0.6 and a contact time of less than 2 hours is applied. 2. The method of claim 1, wherein the fat or oil contains at most 10% bound linoleic acid. 3. The method of claim 2, wherein the fat is sunflower oil having an AOM value of at least 100 hours. 4. The method according to claim 1 or 2, wherein the fat or oil contains olive oil. 5. Claim 1, wherein the fat or oil contains an olein fraction of shea oil, cottonseed oil, or monkey oil.
The method described in Section 1 or Section 2. 6. The method of any one of claims 1 to 5, wherein the lipase is 1,3-specific. 7. The method according to any one of claims 1 to 6, wherein the saturated fatty acid or ester thereof includes palmitic acid, stearic acid, or an alkyl ester thereof. 8. The method according to any one of claims 1 to 7, wherein 1 to 5 moles of fatty acid are used per mole of fat or oil. 9. A process according to any one of claims 1 to 8, wherein the product is recovered from the reaction mixture by fractional crystallization at 10-40<0>C. 10. A process according to any one of claims 1 to 9, wherein the unsaturated by-products recovered from the reaction mixture are hydrogenated and recycled as saturated fatty acids or esters thereof. 11. Confectionery fats comprising symmetrical disaturated triglycerides of palmitic acid and/or stearic acid, in which the saturated fatty acids are randomly distributed between the 1st and 3rd positions, at least 90% of which are 2-oleoyl triglycerides. Yes, fat. 12. The confectionery fat of claim 11, wherein at least 90% of the triglycerides are 2-oleoyl triglycerides.