Grease composition with high content of OPO and OPL and preparation method thereof

Abstract

The invention discloses a grease composition with high content of OPO and OPL and a preparation method of the grease composition, and relates to the technical field of grease synthesis. The product comprises the following raw materials: palmitic acid stearin, sunflower seed fully-hydrolyzed oil, high oleic acid sunflower seed fully-hydrolyzed oil, lipase and water. The preparation method comprises the steps of material preparation, primary enzymolysis, secondary enzymolysis and product preparation. The product grease composition is rich in OPO and OPL, has more functions, and is closer to breast milk composition; the preparation method can better control a target product and by-products, the production efficiency is high, and the whole method is green and environment-friendly in process, good in safety, low in cost and beneficial to industrial large-scale application.

Description

Technical Field

[0001] The present application relates to the technical field of oil synthesis, and in particular to an oil composition with high content of OPO and OPL and a preparation method thereof. Background Art

[0002] Triglycerides (TAG) are the most abundant components in breast milk lipids, accounting for about 98% of all lipids. Among them, 1,3-dioleoyl-2-palmitoylglycerol (1,3-dioleoyl-2-palmitoylglycerol, OPO) and 1-oleoyl-2-palmitoyl-2-linoleoylglycerol (1-oleoyl-2-palmitoyl-3-linoleoylglycerol, OPL) are the two most abundant TAGs in breast milk. This special TAG structure is not only beneficial for improving the baby's absorption of calcium, reducing the loss of calcium in the feces, and reducing constipation and defecation difficulties in the baby, but also can improve the absorption and utilization of fat energy and promote the baby's bone growth and development. At the same time, OPO oil is rich in oleic acid, which can regulate blood lipid levels, lower cholesterol, effectively reduce the occurrence of hypercholesterolemia and cardiovascular diseases, and reduce the chance of coronary heart disease; OPL oil is rich in linoleic acid, which is an essential fatty acid for the human body. It has the effect of lowering cholesterol and preventing atherosclerosis. Linoleic acid is a nutrient for the development of the brain and optic nerves of infants and young children, and plays an important role in improving the intelligence and visual acuity of infants. If infants lack linoleic acid, they will suffer from skin diseases, growth retardation, etc.

[0003] The position of fatty acids on triglycerides affects their digestion and absorption. Palmitic acid in cow's milk and common vegetable oils is mostly distributed at the Sn-1 and 3 positions of triglycerides. Palmitic acid at the Sn-1 and 3 positions will be freed after being hydrolyzed by pancreatic lipase in the body. It is easy to form high-melting-point saponification products with calcium and magnesium ions in the body and be excreted from the body, causing constipation in infants and young children and the loss of nutrients such as palmitic acid and calcium. Fatty acids in human milk fat have unique distribution characteristics. Palmitic acid is mainly distributed at the Sn-2 position, so that palmitic acid exists in the form of Sn-2 fatty acids, which is beneficial for infants to absorb.

[0004] Therefore, there is an urgent need to develop a product that is rich in OPO and OPL, and the triglyceride Sn-2 position is mainly palmitic acid. In particular, the efficient preparation method of OPO and OPL oils is more important. At present, the content of the target substance in the oil mixture prepared by the traditional method is not high, and it is difficult to control the proportion of by-products. In addition, due to the influence of the reaction system, the traditional preparation method will result in a very low number of enzyme repetitions and a high process cost. Summary of the invention

[0005] The purpose of the present application is to provide an oil composition with a high content of OPO and OPL and a preparation method thereof. The product oil composition is rich in OPO and OPL, has more diverse functionality, and is closer to the composition of breast milk; the preparation method can better control the target product and by-products, has high production efficiency, and the entire method process is green and environmentally friendly, has good safety, and low cost, which is conducive to industrial-scale application.

[0006] The technical solution of this application is as follows:

[0007] On the one hand, the present invention provides a grease composition with a high content of OPO and OPL, which is prepared from raw materials comprising the following components:

[0008] Palmitostearin, fully hydrolyzed sunflower seed oil, fully hydrolyzed high oleic sunflower seed oil, lipase and water;

[0009] Among them, in the palmitic acid stearin, the content of tripalmitoyl triglyceride is 40-60%, and the content of 1-oleoyl-2,3-palmitoyl triglyceride is 25-40%;

[0010] The above fully hydrolyzed sunflower seed oil has an oleic acid content of 18-30% and a linoleic acid content of 55-70%;

[0011] The high oleic acid sunflower seed fully hydrolyzed oil has an oleic acid content of 70-85% and a linoleic acid content of 5-15%.

[0012] The above lipase is a sn-1,3 position specific lipase.

[0013] On the other hand, the present invention also provides a method for preparing the above-mentioned grease composition with high content of OPO and OPL, which comprises the following steps:

[0014] Ingredients: palmitic acid stearin, sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil are taken, and the amount of palmitic acid stearin, sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil is determined according to the amount of tripalmitin triglyceride contained in palmitic acid stearin, the amount of oleic acid and linoleic acid contained in the sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil, and the molar ratio of tripalmitin triglyceride, oleic acid and linoleic acid, and the mixture is mixed to obtain a reaction substrate;

[0015] Primary enzymatic hydrolysis: lipase and water are added to the reaction substrate to react, and the product obtained after the reaction is molecularly distilled to obtain a primary residue;

[0016] Secondary enzymatic hydrolysis: adding high oleic acid sunflower seed fully hydrolyzed oil, lipase and water to the primary distillation residue to react, and subjecting the product obtained after the reaction to molecular distillation to obtain the secondary distillation residue;

[0017] Product preparation: The secondary distillation residue is deoxidized and decolorized to obtain a grease composition product with high content of OPO and OPL.

[0018] Compared with the prior art, the embodiments of the present application have at least the following advantages or beneficial effects:

[0019] In the first aspect, the present application provides a grease composition with a high content of OPO and OPL, which is prepared from raw materials comprising the following components:

[0020] Palmitostearin, fully hydrolyzed sunflower seed oil, fully hydrolyzed high oleic sunflower seed oil, lipase and water;

[0021] The above lipase is a sn-1,3 specific lipase. Furthermore, preferably, the lipase is derived from Aspergillus niger, such as the immobilized lipase Skuny SM041 (a product model developed by the applicant), or other lipases derived from Aspergillus niger.

[0022] In the above embodiment, palmitic acid stearin contains tripalmitoyl triglyceride (PPP) and 1-oleoyl-2,3-palmitoyl triglyceride (OPP), and sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil contain oleic acid (OA) and linoleic acid (LA); wherein, palmitic acid stearin comes from palm oil, which is mainly oil extracted from the fruit of palm trees, and is a fat product (in the embodiment of the present application, palm oil) obtained by winterization reaction (physical reaction, crystallization and precipitation at different temperatures according to the different solidification points of the components) by temperature gradient. Palmitostearin 52℃ refers to the component that crystallizes out at 52℃); both fully hydrolyzed sunflower seed oil and high oleic sunflower seed hydrolyzed oil are oils extracted from sunflower seeds. After the hydrolysis reaction, the original triglyceride (TG) oil is converted into free fatty acids (FFA). The sunflower seeds used in fully hydrolyzed sunflower seed oil and high oleic sunflower seed hydrolyzed oil are different, resulting in different OA contents in the two product oils (the OA content in fully hydrolyzed sunflower seed oil is 18-30%, while the OA content in fully hydrolyzed high oleic sunflower seed oil is 70-80%).

[0023] Its raw materials come from a wide range of sources. Although other vegetable oils, such as safflower oil, linseed oil, peanut oil, etc., can also be used, under existing conditions, palmitic acid stearin and sunflower oil are cheaper in terms of raw material and process costs, and can fully meet the demand for obtaining a high-content OPO and OPL oil composition.

[0024] In addition, in the raw materials, the water used is preferably pure water. By adding a certain amount of pure water before starting the reaction, the efficiency of enzyme-catalyzed OA and LA replacing the sn-1,3 palmitic acid of PPP and OPP in the raw materials can be improved, the reaction time can be shortened, and the reaction efficiency can be improved.

[0025] Furthermore, in some embodiments of the present application, in the product oil and fat composition, the total content of OPO and OPL is greater than 65%, and the content of OPL is greater than 45%.

[0026] Regarding the second aspect, the embodiments of the present application also provide a method for preparing the above-mentioned oil and fat composition with high content of OPO and OPL, the steps of which include: batching, primary enzymolysis, secondary enzymolysis and product preparation.

[0027] In the above embodiment, the preparation method adopts a two-step enzymatic method, utilizing the selectivity of the sn-1,3 position of the enzyme to transesterify most of the PPP and OPP in the raw material into a mixture of OPO and OPL, and removes excess FFA by molecular distillation to obtain the first-stage distillation residue TAG, and then adds a raw material containing high OA, and then uses the enzyme to transesterify the first-stage distillation residue TAG again, and removes excess FFA by molecular distillation, and then deoxidizes and decolorizes to obtain the final product; the method can effectively increase the content of the OPL and OPO mixture in the final product to obtain a grease composition rich in OPO and OPL, and can effectively avoid the acyl migration side reaction and control the generation of by-products; the whole process of the method is simple and easy to operate, the reaction conditions are mild, no other toxic solvents are used, it is green and safe, and is conducive to large-scale production and application.

[0028] Furthermore, in some embodiments of the present application, in the above-mentioned ingredient preparation step, the molar ratio of tripalmitin triglyceride, oleic acid and linoleic acid is 1:(4-18):(5-20); preferably PPP:OA:LA=1:(6-12):(8-15); further preferably PPP:OA:LA=1:(8-9):(9-10).

[0029] Furthermore, in some embodiments of the present application, in the above-mentioned enzymatic hydrolysis step, the amount of lipase added is 3-15% of the mass of the reaction substrate, preferably 6-12%; the amount of water added is 0.5-3% of the mass of the reaction substrate; the reaction temperature is 45-65°C, preferably 50-60°C.

[0030] Furthermore, in some embodiments of the present application, in the above-mentioned enzymatic hydrolysis step, the reaction time is 1 to 24 hours, preferably 3 to 20 hours, and more preferably 3 to 12 hours.

[0031] Furthermore, in some embodiments of the present application, in the above-mentioned secondary enzymatic hydrolysis step, the amount of high oleic sunflower seed fully hydrolyzed oil added is 20-40% of the mass of the primary distillation residue; the amount of water added is 0.5-3% of the mass of the reaction substrate; and the reaction temperature is 45-65°C, preferably 50-60°C.

[0032] Furthermore, in some embodiments of the present application, in the above-mentioned secondary enzymatic hydrolysis step, the reaction time is 1 to 24 hours, preferably 3 to 20 hours, and more preferably 3 to 12 hours.

[0033] Furthermore, in some embodiments of the present application, in the above-mentioned primary enzymolysis step, the lipase is collected by filtration after the reaction, and the collected lipase is washed with petroleum ether, then filtered, and then continuously treated with nitrogen; the lipase obtained after the treatment is continuously put into the above-mentioned secondary enzymolysis step for use;

[0034] In the above-mentioned secondary enzymolysis step, the lipase is collected by filtration after the reaction, and the collected lipase is washed with petroleum ether, then filtered, and then continuously treated with nitrogen; the lipase obtained after the treatment is recovered.

[0035] In the above embodiment, by washing the immobilized lipase with petroleum ether, the reactants adhering to the surface of the enzyme particles can be effectively removed, and the residual reactants can be prevented from affecting the activity of the lipase, thereby realizing the recycling and reuse of the lipase, thereby effectively reducing the raw material cost of the lipase and improving the economic benefits of the production process. The number of times the immobilized lipase can be reused after washing can be greatly increased to more than 40 times.

[0036] Furthermore, in some embodiments of the present application, in the above-mentioned primary enzymatic hydrolysis step and the above-mentioned secondary enzymatic hydrolysis step, the petroleum ether used is an environmentally friendly food-grade petroleum ether with a boiling point of 30-120°C, preferably 60-90°C; the petroleum ether washing time is 10-60min, preferably 15-30min; the nitrogen flow rate is 30-100SLPM, preferably 50-80SLPM, and the nitrogen treatment time is 10-60min, preferably 15-30min.

[0037] Further, in some embodiments of the present application, in the above-mentioned primary enzymatic hydrolysis step and the above-mentioned secondary enzymatic hydrolysis step, the reaction is carried out under a vacuum degree of 2 to 50 Pa, preferably a vacuum degree of 3 to 30 Pa;

[0038] The conditions for molecular distillation are: evaporation temperature 160-200°C, rotor speed 1000-1300rpm, pressure 2-10Pa.

[0039] In the above embodiment, a vacuum pump can be used to provide vacuum reaction conditions, which can effectively remove the moisture in the raw materials and the moisture added by the previous reaction, avoid excessive hydrolysis side reactions resulting in excessive production of by-product diacylglycerol (DAG), and affect the content of the OPO and OPL mixture; it can also effectively remove the petroleum ether remaining in the washed lipase, avoiding the damage of the residual petroleum ether to the immobilized carrier resin.

[0040] Furthermore, in some embodiments of the present application, in the above-mentioned primary enzymolysis step and the above-mentioned secondary enzymolysis step, a rotary vane vacuum pump, a screw vacuum pump, a Roots vacuum pump, or a water ring vacuum pump is used to provide vacuum conditions, and the pressure is 20 to 300 Pa, preferably 30 to 100 Pa.

[0041] Furthermore, in some embodiments of the present application, in the above product preparation step, activated clay is used to deoxidize and decolorize the secondary distillation residue, and the amount of activated clay used is 5 to 15% of the mass of the secondary distillation residue;

[0042] The conditions for deoxidation and decolorization are: constant temperature 95-105°C, magnetic stirring speed 150-200rpm, and pressure 10-60Pa.

[0043] In the above embodiments, the molecular distillation method and the activated clay deoxidation and decolorization method are used, the separation effect is good, the product chromaticity is good, the peroxide value and anisidine value in the product are very low, and the safety is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 This is the HPLC-ELSD diagram of the product oil composition in Example 1 of the present application;

[0046] Figure 2 This is the GC graph of the product grease composition in Example 1 of the present application;

[0047] Figure 3 HPLC-ELSD diagram of the product oil composition in Example 2 of the present application;

[0048] Figure 4 This is the GC graph of the product oil composition in Example 2 of the present application;

[0049] Figure 5 HPLC-ELSD diagram of the product oil composition in Example 3 of the present application;

[0050] Figure 6 This is the GC graph of the product oil composition in Example 3 of the present application;

[0051] Figure 7 This is a graph showing the content of the OPO and OPL mixture in the reaction products of the water-added group and the non-water-added group in Comparative Example 1 of the present application;

[0052] Figure 8 This is the GC graph of the reaction products of the water-added group and the non-water-added group in Comparative Example 1 of the present application;

[0053] Fig. 9 This is the GC graph of the products of the nitrogen-passing reaction group and the vacuum reaction group in Comparative Example 2 of the present application;

[0054] Fig.10 This is a graph showing the content of the OPL and OPO mixture in the product continuously produced by the petroleum ether washing group and the direct recovery group in Comparative Example 3 of the present application. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to the conventional conditions or the conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0056] It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "includes..." do not exclude the existence of other identical elements in the process, method, article or device including its elements.

[0057] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application may be combined with each other.

[0058] The features and performance of the present application are further described in detail below in conjunction with the embodiments.

[0059] Example 1

[0060] This embodiment provides a grease composition with high content of OPO and OPL, which is prepared by the following method:

[0061] Ingredients: Take separately:

[0062] Palmitostearin (52°C), wherein the content of tripalmitoyl triglyceride (PPP) is 43.29%, and the content of 1-oleoyl-2,3-palmitoyl triglyceride (OPP) is 36.32%;

[0063] Sunflower seed fully hydrolyzed oil, containing 24.46% oleic acid (OA) and 66.45% linoleic acid (LA);

[0064] High oleic sunflower seed fully hydrolyzed oil, wherein the content of oleic acid (OA) is 83.95%, and the content of linoleic acid (LA) is 7.41%;

[0065] In a solvent-free system, a reaction substrate is prepared by mixing according to a molar ratio of PPP:OA:LA equal to 1:9:10;

[0066] Primary enzymatic hydrolysis: add lipase (immobilized enzyme Skuny SM041) with a mass of 8% of the substrate and pure water with a mass of 0.5% of the substrate to the reaction substrate, and stir the reaction at a vacuum of 30 Pa and 45° C. for 6 h;

[0067] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 90-120°C petroleum ether, and then 50 SLPM of nitrogen is introduced for 20 minutes for use;

[0068] After the reaction product is filtered to remove lipase, molecular distillation is performed under the conditions of evaporation temperature of 200°C, rotor speed of 1100rpm, and pressure of 10Pa to obtain a primary distillation residue;

[0069] Secondary enzymolysis: the nitrogen-treated lipase recovered in the first enzymolysis step, 25% of the mass of high oleic sunflower seed fully hydrolyzed oil, and 0.5% of the mass of pure water were added to the first distillation residue again, and the mixture was stirred and reacted for 6 hours under vacuum conditions of 30 Pa and 45° C.;

[0070] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 90-120°C petroleum ether, and then treated with 50 SLPM nitrogen for 20 minutes before recovery;

[0071] The reaction product was filtered to remove lipase, and then molecularly distilled to remove FFA at an evaporation temperature of 200°C, a rotor speed of 1100 rpm, and a pressure of 10 Pa to obtain a secondary distillation residue;

[0072] Product preparation: Using activated white clay with a material mass content of 12%, deoxygenation and decolorization are carried out at a constant temperature of 95°C, a magnetic stirring speed of 150rpm, and a pressure of 60Pa to reduce the peroxide value and anisidine value to obtain a grease composition product with a high content of OPO and OPL.

[0073] The product grease composition obtained in this example was subjected to HPLC-ELSD and GC analysis, and the results were as follows: Figure 1 and Figure 2 As shown;

[0074] Figure 1The HPLC-ELSD chromatogram of the product oil composition is shown in FIG. 1 . From the right, the second peak on the right is OPL, and the third peak on the right is OPO.

[0075] Figure 2 The gas chromatogram (GC) of the product oil composition, in which the two right peaks from the right are a mixture of OPO and OPL.

[0076] Example 2

[0077] This embodiment provides a grease composition with high content of OPO and OPL, which is prepared by the following method:

[0078] Ingredients: Take separately:

[0079] Palmitostearin (52°C), wherein the content of tripalmitoyl triglyceride (PPP) is 48.58%, and the content of 1-oleoyl-2,3-palmitoyl triglyceride (OPP) is 39.93%;

[0080] Sunflower seed fully hydrolyzed oil, containing 24.46% oleic acid (OA) and 66.45% linoleic acid (LA);

[0081] High oleic sunflower seed fully hydrolyzed oil, wherein the content of oleic acid (OA) is 83.95%, and the content of linoleic acid (LA) is 7.41%;

[0082] In a solvent-free system, a reaction substrate is prepared by mixing according to a molar ratio of PPP:OA:LA equal to 1:8:9;

[0083] Primary enzymatic hydrolysis: add lipase (immobilized enzyme Skuny SM041) with a mass of 6% of the substrate and pure water with a mass of 1% of the substrate to the reaction substrate, and stir the reaction under vacuum conditions of 50 Pa and 60° C. for 10 h;

[0084] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 60-90°C petroleum ether, and then 30 SLPM nitrogen is introduced for 30 min before use;

[0085] After the reaction product is filtered to remove lipase, molecular distillation is performed at an evaporation temperature of 190° C., a rotor speed of 1000 rpm, and a pressure of 3 Pa to obtain a primary distillation residue;

[0086] Secondary enzymolysis: the nitrogen-treated lipase recovered in the first enzymolysis step, 30% of the mass of high oleic sunflower seed fully hydrolyzed oil, and 1% of the mass of pure water were added to the first distillation residue again, and the mixture was stirred and reacted for 10 hours under vacuum conditions of 50 Pa and 60° C.;

[0087] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 60-90°C petroleum ether, and then treated with 30 SLPM nitrogen for 30 min before recovery;

[0088] The reaction product was filtered to remove lipase, and then molecularly distilled to remove FFA at an evaporation temperature of 190°C, a rotor speed of 1000 rpm, and a pressure of 3 Pa to obtain a secondary distillation residue;

[0089] Product preparation: Using 8% activated white clay by mass, deoxidation and decolorization are carried out at a constant temperature of 105°C, a magnetic stirring speed of 200rpm, and a pressure of 20Pa to reduce the peroxide value and anisidine value to obtain a grease composition product with a high content of OPO and OPL.

[0090] The product grease composition obtained in this example was subjected to HPLC-ELSD and GC analysis, and the results were as follows: Figure 3 and Figure 4 As shown;

[0091] Figure 3 The HPLC-ELSD chromatogram of the product oil composition is shown in FIG. 1 . From the right, the second peak on the right is OPL, and the third peak on the right is OPO.

[0092] Figure 4 The gas chromatogram (GC) of the product oil composition, in which the two right peaks from the right are a mixture of OPO and OPL.

[0093] Example 3

[0094] This embodiment provides a grease composition with high content of OPO and OPL, which is prepared by the following method:

[0095] Ingredients: Take separately:

[0096] Palmitostearin (52°C), wherein the content of tripalmitoyl triglyceride (PPP) is 47.71%, and the content of 1-oleoyl-2,3-palmitoyl triglyceride (OPP) is 38.88%;

[0097] Sunflower seed fully hydrolyzed oil, containing 24.46% oleic acid (OA) and 66.45% linoleic acid (LA);

[0098] High oleic sunflower seed fully hydrolyzed oil, wherein the content of oleic acid (OA) is 83.95%, and the content of linoleic acid (LA) is 7.41%;

[0099] In a solvent-free system, a reaction substrate is prepared by mixing according to a molar ratio of PPP:OA:LA equal to 1:4:5;

[0100] Primary enzymatic hydrolysis: add lipase (immobilized enzyme Skuny SM041) with a mass of 12% of the substrate and pure water with a mass of 3% of the substrate to the reaction substrate, and stir the reaction under vacuum conditions of 20 Pa and 55°C for 3 h;

[0101] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 30-60°C petroleum ether, and then 80 SLPM of nitrogen is introduced for 10 minutes for use;

[0102] After the reaction product is filtered to remove lipase, molecular distillation is performed under the conditions of evaporation temperature of 200°C, rotor speed of 1000rpm, and pressure of 5Pa to obtain a primary distillation residue;

[0103] Secondary enzymolysis: the nitrogen-treated lipase recovered in the first enzymolysis step, 35% of the mass of high oleic sunflower seed fully hydrolyzed oil, and 3% of the mass of pure water were added to the first distillation residue again, and the mixture was stirred and reacted for 3 hours under vacuum conditions of 20 Pa and 55° C.;

[0104] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 30-60°C petroleum ether, and then treated with 80 SLPM nitrogen for 10 minutes before recovery;

[0105] The reaction product was filtered to remove lipase, and then molecularly distilled to remove FFA at an evaporation temperature of 200°C, a rotor speed of 1000 rpm, and a pressure of 5 Pa to obtain a secondary distillation residue;

[0106] Product preparation: Using activated white clay with a mass content of 10%, deoxidation and decolorization were carried out at a constant temperature of 95°C, a magnetic stirring speed of 200 rpm, and a pressure of 40 Pa to reduce the peroxide value and anisidine value, and obtain a grease composition product with a high content of OPO and OPL.

[0107] The product grease composition obtained in this example was subjected to HPLC-ELSD and GC analysis, and the results were as follows: Figure 5 and Figure 6 As shown;

[0108] Figure 5 The HPLC-ELSD chromatogram of the product oil composition is shown in FIG. 1 . From the right, the second peak on the right is OPL, and the third peak on the right is OPO.

[0109] Figure 6 The gas chromatogram (GC) of the product oil composition, in which the two right peaks from the right are a mixture of OPO and OPL.

[0110] Comparative Example 1

[0111] The specifications of palmitic acid stearin, sunflower seed fully hydrolyzed oil, and high oleic acid sunflower seed fully hydrolyzed oil used in this comparative example are the same as those in Example 3, and the molar ratio of PPP:OA:LA in the reaction substrate is also the same as in Example 3, which is 1:4:5;

[0112] Based on the above conditions, a water-added group and a non-water-added group were divided for comparative experiments;

[0113] The subsequent method for the water-addition group was:

[0114] Primary enzymatic hydrolysis: add lipase (immobilized enzyme Skuny SM041) with a mass of 6% of the substrate and pure water with a mass of 3% of the substrate to the reaction substrate, stir and react for 3 hours under vacuum conditions of 10Pa and 55°C, and take samples every hour to detect the content of the mixture of OPO and OPL in the material;

[0115] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 60-90°C petroleum ether, and then 50 SLPM of nitrogen is introduced for 10 minutes for use;

[0116] The reaction product is filtered to remove lipase, and then molecularly distilled to obtain a primary residue;

[0117] Secondary enzymolysis: add the nitrogen-treated lipase recovered in the first enzymolysis step, 30% of the mass of high oleic sunflower seed fully hydrolyzed oil, and 1% of the mass of pure water to the first distillation residue, stir and react for 3 hours under vacuum conditions of 10Pa and 55°C, and take samples every hour to detect the content of the mixture of OPO and OPL in the material;

[0118] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 60-90°C petroleum ether, and then treated with 50 SLPM nitrogen for 10 minutes before recovery;

[0119] The reaction product is filtered to remove lipase, and then subjected to molecular distillation to remove FFA to obtain the product;

[0120] The subsequent method of the group without water addition was basically the same as that of the group with water addition, except that pure water was not added in the first and second enzymatic hydrolysis steps of the group without water addition; and the content of the OPO and OPL mixture in the products of the first and second enzymatic hydrolysis steps was detected every hour according to the method of the group with water addition.

[0121] The results are as follows Figure 7 As shown, Figure 7 In the middle, the left figure is the water-added group. It can be seen from the figure that after 1 h of reaction, the content of OPO and OPL mixture is >40%;

[0122] Figure 7The right picture is the group without water addition. It can be seen from the picture that after 1 hour of reaction, the content of OPO and OPL mixture is <40%, indicating that the reaction efficiency of the group with water addition is higher.

[0123] The GC analysis of the products of the water-added group and the non-water-added group is shown in Figure 8 As shown in the figure, from the right, the second right peak is a mixture of OPO and OPL.

[0124] Comparative Example 2

[0125] The specifications of palmitic acid stearin, sunflower seed fully hydrolyzed oil, and high oleic acid sunflower seed fully hydrolyzed oil used in this comparative example are the same as those in Example 3, and the molar ratio of PPP:OA:LA in the reaction substrate is also the same as in Example 3, which is 1:4:5;

[0126] Based on the above conditions, a nitrogen reaction group and a vacuum reaction group were divided for comparative experiments;

[0127] The subsequent method of the nitrogen-filled reaction group is:

[0128] Primary enzymatic hydrolysis: add lipase (immobilized enzyme Skuny SM041) at 8% of the substrate mass to the reaction substrate, and stir the reaction at 55°C for 3 h while continuously passing nitrogen at a rate of 80 SLPM;

[0129] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 30-60°C petroleum ether, and then 80 SLPM of nitrogen is introduced for 10 minutes for use;

[0130] The reaction product is filtered to remove lipase, and then molecularly distilled to obtain a primary residue;

[0131] Secondary enzymolysis: add the nitrogen-treated lipase recovered in the first enzymolysis step and 30% of the mass of high oleic sunflower seed fully hydrolyzed oil to the first distillation residue again, and stir and react for 3 hours at 55° C. under the conditions of continuous nitrogen flow of 80 SLPM;

[0132] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 30-60°C petroleum ether, and then treated with 80 SLPM nitrogen for 10 minutes before recovery;

[0133] The reaction product is filtered to remove lipase, and then subjected to molecular distillation to remove FFA to obtain the product;

[0134] The subsequent method of the vacuum reaction group is basically the same as that of the nitrogen reaction group, except that in the primary and secondary enzymatic hydrolysis steps of the vacuum reaction group, after adding lipase, the reaction is stirred for 3 hours under vacuum conditions of 5Pa and 55°C.

[0135] The products obtained from the nitrogen reaction group and the vacuum reaction group were analyzed by GC. Fig. 9 As shown;

[0136] Fig. 9 In the middle, from the right, the second peak on the right is a mixture of OPO and OPL; from the left, the first, second, and third peaks on the left are DAG;

[0137] Fig. 9 In the figure above, the nitrogen-passing reaction group has a higher DAG peak at 6-7.5 min, and the content of the product OPO and OPL mixture is relatively reduced.

[0138] Fig. 9 The figure below is the vacuum reaction group. It can be seen that the DAG peak at 6-7.5min is lower, and the content of the product OPO and OPL mixture is relatively increased.

[0139] Comparative Example 3

[0140] The specifications of palmitic acid stearin, sunflower seed fully hydrolyzed oil, and high oleic acid sunflower seed fully hydrolyzed oil used in this comparative example are the same as those in Example 3, and the molar ratio of PPP:OA:LA in the reaction substrate is also the same as in Example 3, which is 1:4:5;

[0141] Based on the above conditions, a comparative experiment was conducted between a petroleum ether washing group and a direct recovery group.

[0142] The subsequent method of the petroleum ether washing group is:

[0143] Primary enzymatic hydrolysis: add lipase (immobilized enzyme Skuny SM041) with a mass of 12% of the substrate and pure water with a mass of 1% of the substrate to the reaction substrate, and stir the reaction under vacuum conditions of 10 Pa and 50° C. for 3 h;

[0144] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 60-90°C petroleum ether, and then 80 SLPM of nitrogen is introduced for 10 minutes for use;

[0145] The reaction product is filtered to remove lipase, and then molecularly distilled to obtain a primary residue;

[0146] Secondary enzymolysis: add the nitrogen-treated lipase recovered in the first enzymolysis step, 25% of the mass of high oleic sunflower seed fully hydrolyzed oil, and 1% of the mass of pure water to the first distillation residue, and stir and react for 3 hours under vacuum conditions of 10 Pa and 50° C.;

[0147] After the reaction is completed, the reaction product is filtered through a plate and frame method to remove lipase, and the lipase is washed with 60-90°C petroleum ether, and then treated with 80 SLPM nitrogen for 10 minutes before recovery;

[0148] The reaction product is filtered to remove lipase, and then subjected to molecular distillation to remove FFA to obtain the product;

[0149] The subsequent method of the direct recovery group is basically the same as that of the petroleum ether washing group. The difference is that in the direct recovery group, in the primary enzymatic hydrolysis step, the plate and frame filtration method is used to remove the lipase after the reaction, and the lipase is not washed with petroleum ether, but is directly put into the secondary enzymatic hydrolysis step for use. In the secondary enzymatic hydrolysis step, the lipase is removed by filtration after the reaction, and is also not washed with petroleum ether, but is directly recovered.

[0150] According to the two groups' respective methods, the recovered lipase was repeatedly recovered and put into production, and the content of the OPO and OPL mixture in the final product obtained each time was tested. The results are as follows: Fig.10 As shown;

[0151] Fig.10 The left figure shows the content of the mixture of OPO and OPL in the product of the petroleum ether washing group. It can be seen that when the lipase is washed with petroleum ether and repeatedly recycled and put into production for 40 times, the content of the mixture of OPO and OPL in the product is still >40%;

[0152] Fig.10 The right figure shows the content of the mixture of OPO and OPL in the direct recovery group's continuous repeated production products. It can be seen that after the lipase was directly filtered and recovered and repeatedly recycled and put into production for 11 times, the content of the mixture of OPO and OPL in the product was less than 40%, and the product quality did not meet the standard. This shows that the lipase can be reused more times after washing with petroleum ether, and the content of the mixture of OPO and OPL in the product is more stable.

[0153] In summary, the embodiments of the present application provide a grease composition with a high content of OPO and OPL and a preparation method thereof. The preparation method adopts a two-step enzymatic method, which can effectively increase the content of OPL and OPO mixture in the final product to obtain a grease composition rich in OPO and OPL, and can effectively avoid acyl migration side reactions and control the generation of by-products. The method is simple and easy to operate throughout the process, has mild reaction conditions, does not use other toxic solvents, and is green and safe. The raw materials are widely available, and the raw material and process costs are lower, which is conducive to large-scale production and application.

[0154] The embodiments described above are part of the embodiments of the present application, rather than all of the embodiments. The detailed description of the embodiments of the present application is not intended to limit the scope of the present application for protection, but merely represents the selected embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

Claims

1. A grease composition with high content of OPO and OPL, characterized in that: It is prepared from raw materials comprising the following components: Palmitostearin, fully hydrolyzed sunflower seed oil, fully hydrolyzed high oleic sunflower seed oil, lipase and water; Wherein, in the palmitic acid stearin, the content of tripalmitoyl triglyceride is 40-60%, and the content of 1-oleoyl-2,3-palmitoyl triglyceride is 25-40%; The fully hydrolyzed sunflower seed oil has an oleic acid content of 18-30% and a linoleic acid content of 55-70%; The high oleic acid sunflower seed fully hydrolyzed oil has an oleic acid content of 70-85% and a linoleic acid content of 5-15%; The lipase is a sn-1,3 position specific lipase.

2. A grease composition with high content of OPO and OPL according to claim 1, characterized in that, The lipase is selected from the lipase derived from Aspergillus niger.

3. A method for preparing a grease composition having a high content of OPO and OPL as claimed in any one of claims 1 to 2, characterized in that: It includes the following steps: Ingredients: palmitic acid stearin, sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil are taken, and the amount of palmitic acid stearin, sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil is determined according to the amount of tripalmitin triglyceride contained in palmitic acid stearin, the amount of oleic acid and linoleic acid contained in the sunflower seed fully hydrolyzed oil and high oleic acid sunflower seed fully hydrolyzed oil, and the molar ratio of tripalmitin triglyceride, oleic acid and linoleic acid, and the mixture is mixed to obtain a reaction substrate; Primary enzymatic hydrolysis: lipase and water are added to the reaction substrate to react, and the product obtained after the reaction is molecularly distilled to obtain a primary residue; Secondary enzymatic hydrolysis: adding high oleic acid sunflower seed fully hydrolyzed oil, lipase and water to the primary distillation residue to react, and subjecting the product obtained after the reaction to molecular distillation to obtain the secondary distillation residue; Product preparation: The secondary distillation residue is deoxidized and decolorized to obtain a grease composition product with high content of OPO and OPL.

4. The method for preparing a grease composition having a high content of OPO and OPL according to claim 3, characterized in that: In the step of preparing ingredients, the molar ratio of tripalmitin triglyceride, oleic acid and linoleic acid is 1:(4-18):(5-20).

5. The method for preparing a grease composition having a high content of OPO and OPL according to claim 3, characterized in that: In the primary enzymatic hydrolysis step, the amount of lipase added is 3-15% of the mass of the reaction substrate; the amount of water added is 0.5-3% of the mass of the reaction substrate; and the reaction temperature is 45-65°C.

6. The method for preparing a grease composition having a high content of OPO and OPL according to claim 3, characterized in that: In the secondary enzymolysis step, the amount of high oleic sunflower seed fully hydrolyzed oil added is 20-40% of the mass of the primary distillation residue; the amount of water added is 0.5-3% of the mass of the reaction substrate; and the reaction temperature is 45-65°C.

7. The method for preparing a grease composition having a high content of OPO and OPL according to claim 3, characterized in that: In the primary enzymolysis step, the lipase is collected by filtration after the reaction, and the collected lipase is washed with petroleum ether, then filtered, and then continuously treated with nitrogen; the lipase obtained after the treatment is continuously put into the secondary enzymolysis step for use; In the secondary enzymolysis step, the lipase is collected by filtration after the reaction, and the collected lipase is washed with petroleum ether, then filtered, and then continuously treated with nitrogen; the lipase obtained after the treatment is recovered.

8. The method for preparing a grease composition having a high content of OPO and OPL according to claim 7, characterized in that: In the primary enzymolysis step and the secondary enzymolysis step, the petroleum ether used is environmentally friendly food-grade petroleum ether with a boiling point of 30 to 120° C.; the petroleum ether washing time is 10 to 60 minutes; the nitrogen flow rate is 30 to 100 SLPM, and the nitrogen treatment time is 10 to 60 minutes.

9. The method for preparing a grease composition having a high content of OPO and OPL according to claim 3, characterized in that: In the first enzymatic hydrolysis step and the second enzymatic hydrolysis step, the reactions are carried out under a vacuum degree of 2 to 50 Pa; The conditions for molecular distillation are: evaporation temperature 160-200°C, rotor speed 1000-1300rpm, pressure 2-10Pa.

10. The method for preparing a grease composition having a high content of OPO and OPL according to claim 3, characterized in that: In the product preparation step, activated clay is used to deoxidize and decolorize the secondary distillation residue, and the amount of activated clay used is 5-15% of the mass of the secondary distillation residue; The conditions for deoxidation and decolorization are: constant temperature 95-105°C, magnetic stirring speed 150-200rpm, and pressure 10-60Pa.

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