A kind of deacidification method of OPO structure fat

Abstract

The invention discloses a deacidification method for OPO structural fat, comprising the following steps: weighing the OPO structural fat to be deacidified, and determining the acid value; preparing a deacidification reagent; adding the deacidification reagent to the OPO structural fat, and filtering after the reaction to obtain the OPO structural fat with an acid value less than 1 mgKOH / g. The deacidification method of the invention uses octanoic acid glyceride as a skeleton to support a self-made deacidification reagent with a layered structure, which can effectively adsorb free fatty acids in the OPO structural fat, and effectively reduce the saponification of the OPO structural fat itself, thereby obtaining an OPO structural fat product with a low acid value, and can effectively avoid the rearrangement of fatty acids in the OPO structural fat. The rearrangement rate of fatty acids in the OPO structural fat is reduced from 10% in the conventional deacidification using a sodium hydroxide method to less than 1%; the invention selects octanoic acid glyceride, which has a better effect on reducing the rearrangement rate of fatty acids in the OPO structural fat than the literature records that adding p-toluenesulfonic acid has a better effect, and experiments have found that the addition of p-toluenesulfonic acid has a limited effect on the rearrangement, and p-toluenesulfonic acid also has an effect on the safety of OPO.

Description

Technical Field

[0001] The invention belongs to the technical field of organic synthesis of structural lipids, relates to OPO structural lipids, and in particular to a deacidification method of OPO structural lipids. Background Art

[0002] 3-Dioleyl-2-palmitoyl triglyceride (OPO) is an important component of human milk fat, accounting for 20% to 40% of the total amount. Studies have shown that adding OPO to infant formula can promote the absorption of fatty acids by infants, effectively reduce the possibility of calcium soap production, reduce the difficulty of defecation in infants, and improve the absorption and utilization of energy and minerals by infants, reduce the lack of calcium, magnesium ions and other nutrients in the body, and promote the natural growth of infants' physique and bones.

[0003] When the OPO process is produced by transesterification reaction of oleic acid and palm stearin catalyzed by Sn-1,3 specific lipase, the reaction product will contain a large amount of fatty acids, which will affect the analysis of key data such as OPO content and SN-2 palmitic acid content, and will also cause problems such as instability of OPO and decrease in OPO content during storage. Therefore, separation and purification of triglycerides and fatty acids (unreacted oleic acid replaced by stearic acid and other fatty acids replaced in oleic acid) is a very important process.

[0004] The usual method for removing free fatty acids is molecular distillation. However, during molecular distillation operation, it was found that when OPO is distilled to an acid value below 5 mgKOH / g, the required temperature is high and OPO is easier to rearrange. Moreover, under this distillation condition, OPO is more likely to enter the light component, resulting in a decrease in the yield of OPO distillation.

[0005] The traditional process often uses molecular distillation to roughly evaporate OPO to an acid value of about 5, and then adopts the traditional alkali refining process. This method uses dilute sodium hydroxide, which is easier to cause saponification of OPO, making it difficult to reduce the acid value to the requirements of the OPO finished product index. There is a lot of excess alkali solution. At the same time, due to the presence of sodium hydroxide, it is easier to cause the rearrangement of fatty acids in OPO, thereby causing the purity of OPO to decrease.

[0006] Literature records the use of alkaline calcium-based bentonite to alkali refine oils and fats, but this method is less suitable for OPO deacidification, and the rearrangement rate of OPO is still high.

[0007] Chinese patent application number CN201110105852.3 relates to a process and equipment in the oil refining process, in which alkali solution and oil are mixed by a centrifugal mixing pump, and then continue to mix through a long pipeline, and then heat and separate. However, this method will produce a large amount of wastewater, and the method is less suitable for OPO deacidification.

[0008] Chinese patent application number CN202010824952.0 discloses a method for deacidification of high-acid-value oils and fats, which uses a specific carrier as a "reservoir" for glycerol to improve the reaction activity of lipase-catalyzed esterification of glycerol and fatty acids. However, there are problems such as high enzyme costs and high requirements for reaction temperature control that limit industrial development. Summary of the invention

[0009] In order to solve the above problems, the present invention discloses a deacidification method for OPO structured lipids, which directly deacidifies the OPO structured lipids using a deacidification reagent, thereby effectively reducing the acid value and the rearrangement rate of the OPO structured lipids under alkaline conditions.

[0010] In order to achieve the above object, the present invention adopts the following technical solutions:

[0011] A deacidification method for OPO structured fat, the deacidification method comprising the following steps:

[0012] 1) Weigh the OPO structured lipid to be deacidified and determine the acid value;

[0013] 2) preparing a deacidification reagent;

[0014] 3) adding the deacidification reagent obtained in step 2) to the OPO structured lipid in step 1), filtering after the reaction to obtain an OPO structured lipid having an acid value of less than 1 mgKOH / g;

[0015] The OPO structured fat that needs to be deacidified is an OPO structured fat product that has been deacidified by molecular distillation in the early stage.

[0016] As a preferred embodiment of the present invention, the acid value of the OPO structured lipid to be deacidified is within 20 mgKOH / g.

[0017] As a preferred embodiment of the present invention, in step 2), the deacidification agent is prepared by first stirring calcium base, octanoic acid glyceride and ethanol to react, then adding activated clay to make a slurry and reacting, and finally completely burning to obtain a deacidification agent of 50-200 mesh.

[0018] As a preferred embodiment of the present invention, the weight ratio of the calcium base, octanoic acid glyceride, ethanol and activated clay is 1:3-5:10-50:10-30.

[0019] As a preferred embodiment of the present invention, the stirring reaction temperature is 80° C. and the stirring reaction time is 2 h.

[0020] As a preferred embodiment of the present invention, the reaction temperature after adding activated clay to the slurry is 250°C to 300°C, the reaction time is 2h to 3h; and the temperature of the burning reaction is 800°C.

[0021] As a preferred embodiment of the present invention, the calcium-based alkali includes calcium hydroxide or calcium oxide.

[0022] More preferably, the calcium-based base is calcium hydroxide.

[0023] As a preferred embodiment of the present invention, in step 3), the amount of the deacidification reagent added is such that the molar ratio of the anion exchange capacity in the deacidification reagent to the free fatty acids in the OPO structured lipid is 1:1-3.

[0024] As a preferred embodiment of the present invention, in step 3), the reaction temperature is 50°C to 80°C after the deacidification reagent is added.

[0025] As a preferred embodiment of the present invention, in step 3), the reaction time after the deacidification reagent is added is 1 h to 3 h.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1) The deacidification method of the present invention utilizes octanoic acid glyceride as a skeleton to support a homemade deacidification reagent with a layered structure, which can effectively adsorb free fatty acids in OPO structured fats and effectively reduce the saponification of OPO structured fats themselves to obtain an OPO structured fat product with a low acid value.

[0028] 2) The deacidification method of the present invention utilizes octanoic acid glyceride as a skeleton to support a homemade deacidification reagent with a layered structure, which effectively reduces the acid value of OPO structural fat and can effectively avoid the rearrangement of fatty acids in the OPO structural fat. The rearrangement rate of fatty acids in the OPO structural fat is reduced from 10% in the conventional deacidification using a sodium hydroxide method to less than 1%; the present invention selects octanoic acid glyceride, which has a better effect on reducing the rearrangement rate of fatty acids in the OPO structural fat than the literature records that adding p-toluenesulfonic acid has a better effect on reducing the rearrangement rate of fatty acids in the OPO structural fat. Experiments have found that the addition of p-toluenesulfonic acid has limited effect on the rearrangement, and p-toluenesulfonic acid also has an impact on the safety of OPO.

[0029] 3) Compared with the traditional NaOH alkali refining method, the deacidification method of the present invention avoids a series of sewage problems caused by using dilute alkali alkali refining. DETAILED DESCRIPTION

[0030] In order to make the technical means, creative features, purpose and efficacy of the present invention easy to understand, the present invention is further described below in conjunction with specific embodiments, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work all belong to the protection scope of the present invention. The experimental methods in the following embodiments, unless otherwise specified, are conventional methods, and the materials, reagents, etc. used in the following embodiments, unless otherwise specified, can all be obtained from commercial channels.

[0031] Example 1

[0032] This embodiment discloses a method for deacidification of an OPO structured lipid, comprising:

[0033] Preparation of deacidification reagent: first, calcium hydroxide, octanoic acid glyceride, and ethanol are stirred and reacted at 80°C in a weight ratio of 1:4:20 for 2 hours; then, activated white clay is added to make a mixed slurry and reacted at 250-300°C for 2-3 hours; finally, it is completely burned at 800°C to finally obtain a 100-mesh deacidification reagent.

[0034] Weigh 100 g of OPO structural fat, determine the acid value to be 4.21 KOH / (mg / g), add 3.52 g of deacidification reagent, react at 60°C for 2 h, and filter to obtain the finished OPO; test the main quality indicators of the product in accordance with the standard "GB 30604-2015 National Food Safety Standard Food Nutrition Fortifier 1,3-dioleoyl-2-palmitoylglycerol".

[0035] Example 2

[0036] This embodiment discloses a method for deacidification of an OPO structured lipid, comprising:

[0037] Preparation of deacidification reagent: First, calcium oxide, octanoic acid glyceride and ethanol are stirred and reacted at 80°C in a weight ratio of 1:4:20 for 2 hours; then activated white clay is added to make a mixed slurry and reacted at 250-300°C for 2-3 hours; finally, it is completely burned at 800°C to finally obtain a 100-mesh deacidification reagent.

[0038] Weigh 100 g of OPO structural fat, determine the acid value to be 4.21 KOH / (mg / g), add 2.59 g of deacidification reagent, react at 60°C for 2 hours, and filter to obtain the finished OPO; test the main quality indicators of the product in accordance with the standard "GB 30604-2015 National Food Safety Standard Food Nutrition Fortifier 1,3-dioleoyl-2-palmitoylglycerol".

[0039] Example 3

[0040] This embodiment discloses a method for deacidification of an OPO structured lipid, comprising:

[0041] Preparation of deacidification reagent: first, calcium hydroxide, octanoic acid glyceride, and ethanol are stirred and reacted at 80°C in a weight ratio of 1:4:20 for 2 hours; then, activated white clay is added to make a mixed slurry and reacted at 250-300°C for 2-3 hours; finally, it is completely burned at 800°C to finally obtain a 100-mesh deacidification reagent.

[0042] Weigh 100 g of OPO structural fat, determine the acid value to be 9.56 KOH / (mg / g), add 7.80 g of deacidification reagent, react at 60°C for 2 hours, and filter to obtain the finished OPO; test the main quality indicators of the product in accordance with the standard "GB 30604-2015 National Food Safety Standard Food Nutrition Fortifier 1,3-dioleoyl-2-palmitoylglycerol".

[0043] Example 4

[0044] This embodiment discloses a method for deacidification of an OPO structured lipid, comprising:

[0045] Preparation of deacidification reagent: first, calcium hydroxide, octanoic acid glyceride, and ethanol are stirred and reacted at 80°C in a weight ratio of 1:5:20 for 2 hours; then activated white clay is added to make a mixed slurry and reacted at 250-300°C for 2-3 hours; finally, it is completely burned at 800°C to finally obtain a 100-mesh deacidification reagent.

[0046] Weigh 100 g of OPO structural fat, determine the acid value to be 4.21 KOH / (mg / g), add 3.52 g of deacidification reagent, react at 60°C for 2 h, and filter to obtain the finished OPO; test the main quality indicators of the product in accordance with the standard "GB 30604-2015 National Food Safety Standard Food Nutrition Fortifier 1,3-dioleoyl-2-palmitoylglycerol".

[0047] Comparative Example 1

[0048] Weigh 100 g of OPO structural fat, determine the acid value to be 4.21 KOH / (mg / g), add 6 g of 5% aqueous solution of NaOH, react at 60°C for 2 h, and filter to obtain the finished OPO; test the main quality indicators of the product in accordance with the standard "GB 30604-2015 National Food Safety Standard Food Nutrition Fortifier 1,3-dioleoyl-2-palmitoylglycerol".

[0049] Comparative Example 2

[0050] Preparation of deacidification reagent: First, calcium hydroxide, water and activated clay are reacted at a weight ratio of 1:7:4 at 250-300°C for 2-3 hours; finally, they are completely burned at 800°C to obtain a 100-mesh deacidification reagent.

[0051] Weigh 100 g of OPO structural fat, determine the acid value to be 4.21 KOH / (mg / g), add 3.36 g of deacidification reagent, react at 60°C for 2 hours, and filter to obtain the finished OPO; test the main quality indicators of the product in accordance with the standard "GB 30604-2015 National Food Safety Standard Food Nutrition Fortifier 1,3-dioleoyl-2-palmitoylglycerol".

[0052] Table 1 Comparison of main OPO indicators of samples after deacidification and molecular distillation

[0053]

[0054]

[0055] It can be seen from Table 1 that according to the methods of Comparative Examples 1 and 2, the acid value of the OPO finished product after deacidification is 0.68KOH / (mg / g) and 0.49KOH / (mg / g), and the acid value of the product meets the index requirements, but the content of 1,3-dioleoyl-3-palmitoyl triglyceride is reduced; when deacidification is carried out using the method of Example 1-4, the content of 1,3-dioleoyl-3-palmitoyl triglyceride remains basically unchanged, and the acid value is reduced to below 1KOH / (mg / g), which increases the content of 1,3-dioleoyl-3-palmitoyl triglyceride compared with the traditional sodium hydroxide deacidification method.

[0056] The above is only a preferred embodiment of the present invention, and is not any formal or substantial limitation of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the method of the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession, without departing from the spirit and scope of the present invention, can make some changes, modifications and evolutions of the technical content disclosed above, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A method for deacidification of OPO structured fat, characterized in that: The deacidification method comprises the following steps: 1) Weigh the OPO structural lipid to be deacidified and determine the acid value; 2) preparing a deacidification agent, firstly stirring calcium-based alkali, octanoic acid glyceride and ethanol to react, the stirring reaction temperature is 80°C, and the stirring reaction time is 2h; then adding activated clay to make a slurry and reacting, and finally burning completely to obtain a 50-200 mesh deacidification agent; the weight ratio of the calcium-based alkali, octanoic acid glyceride, ethanol and activated clay is 1:3~5:10~50:10~30; the reaction temperature after adding activated clay to the slurry is 250°C~300°C, and the reaction time is 2h~3h; the burning reaction temperature is 800°C; the calcium-based alkali includes calcium hydroxide or calcium oxide; 3) adding the deacidification reagent obtained in step 2) to the OPO structured lipid in step 1), filtering after the reaction to obtain an OPO structured lipid having an acid value of less than 1 mgKOH / g; The OPO structured fat that needs to be deacidified is an OPO structured fat product that has been deacidified by molecular distillation in the early stage.

2. The deacidification method of an OPO structured lipid according to claim 1, characterized in that: The acid value of the OPO structured lipid that needs to be deacidified is within 20 mgKOH / g.

3. The deacidification method of an OPO structured lipid according to claim 1, characterized in that: In step 3), the amount of the deacidification reagent added is such that the molar ratio of the anion exchange capacity in the deacidification reagent to the free fatty acids in the OPO structured lipid is 1:1-3.

4. The deacidification method of an OPO structured lipid according to claim 1, characterized in that: In step 3), the reaction temperature is 50°C to 80°C after the deacidification reagent is added.

5. The deacidification method of an OPO structured lipid according to claim 1, characterized in that: In step 3), the reaction time after the deacidification reagent is added is 1 h to 3 h.

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