Refining process of medicinal olive oil

Abstract

The invention discloses a refining process of medicinal olive oil, which is used for refining olive oil by adopting the steps of alkali washing, water removal, adsorbent treatment, low-temperature treatment and the like, can remove impurities which are difficult to remove by a conventional oil refining method and improve the quality of the olive oil, and has the advantages of simple process, easiness in operation, low cost and the like compared with a common refining method. And the product has stable quality, completely meets the quality requirement of the medicinal olive oil, and has a remarkable prospect in industrial refining of the medicinal olive oil.

Description

Technical Field

[0001] The invention relates to the technical field of olive oil refining, in particular to a refining process of medicinal grade olive oil. Background Art

[0002] Food grade olive oil is a common edible oil, which is made from ripe olive fruits by low temperature pressing, and then simply left to settle to remove a small amount of water and impurities, without any refining treatment. It is a yellow-green clear liquid with a special smell, and its oleic acid content is relatively high, generally above 60%, and even up to 80%; olive oil is miscible with common organic solvents such as acetone, ethyl acetate, chloroform and ether, but is very slightly soluble in alcohols such as ethanol, and is almost insoluble in water.

[0003] In the food industry, most food-grade olive oils are simply filtered, separated, and processed to remove moisture and other impurities, and are rarely refined.

[0004] At present, the main refining treatment methods in the oil and fat industry include degumming, deacidification, decolorization, dehydration, deodorization, winterization, etc. The refined oil and fat after treatment basically meets the edible standards. However, in the pharmaceutical field, the following points need to be paid special attention to during the refining process of oil and fat products:

[0005] (1) Whether there is a chemical reaction and whether any by-products are produced;

[0006] (2) Risk of introducing foreign impurities;

[0007] (3) Safety of the main components of oils and fats;

[0008] (4) Removal of impurities.

[0009] Based on this, in the pharmaceutical industry, the quality of oil products needs to be strictly monitored. In the above refining steps, the sterol content in olive oil varies, and the content of some sterols exceeds the limit, resulting in unqualified olive oil and cannot be used in the pharmaceutical industry.

[0010] Medicinal grade olive oil has extremely high quality requirements, especially for color, acid value, peroxide and its degradation products, sterol content, etc. In view of the shortcomings of existing products and technologies, it is urgent to develop an olive oil refining process with simple process flow and stable product quality. Summary of the invention

[0011] The invention provides a refining process for medicinal grade olive oil, which meets the quality requirements of medicinal grade olive oil through a simple and efficient process.

[0012] In view of this, the scheme of the present invention is:

[0013] A refining process for medicinal grade olive oil, comprising the following steps:

[0014] S1. Slowly stir and filter the olive oil at low temperature;

[0015] S2. After the filtered olive oil was heated and stirred, a sodium hydroxide solution was added and stirred, the upper layer was separated after standing, and the oil phase was washed with water to obtain an oil phase;

[0016] S3. Add a dehydrating agent to the oil phase, dehydrate under stirring and let stand, collect the oil layer to obtain the oil phase II;

[0017] S4. Add the first adsorbent to the oil phase II, adsorb under stirring, and filter to obtain the oil phase III;

[0018] S5. Add the second adsorbent to the oil phase three, adsorb under stirring, and filter to obtain pharmaceutical grade olive oil;

[0019] The first adsorbent is thermally activated activated clay;

[0020] The second adsorbent is selected from at least one of activated clay, activated carbon, neutral alumina and silica gel.

[0021] Further, in step S1:

[0022] The low temperature condition is 0-10°C, and the stirring treatment time is 15-25h;

[0023] And / or, the stirring speed is 5-15 r / min.

[0024] Further, in step S2:

[0025] The temperature is raised to 50-70°C.

[0026] And / or, the concentration of the sodium hydroxide solution is 5wt%, and the mass ratio of the sodium hydroxide solution to the olive oil is (0.008-0.011):1;

[0027] And / or, the standing time is 0.5-2h.

[0028] Further, in step S3:

[0029] The dehydrating agent is selected from at least one of calcium chloride, activated alumina powder, molecular sieve activation powder, dry molecular sieve, silica-alumina gel, and water-resistant aluminum silica gel;

[0030] And / or, the mass ratio of the dehydrating agent to the olive oil is (0.02-0.05):1.

[0031] Furthermore, the preparation process of the thermally activated activated clay is to heat the activated clay to 100-110° C. under vacuum, activate it for 30 minutes, and then cool it to obtain the thermally activated activated clay.

[0032] Further, in step S4:

[0033] The adsorption conditions are 60-80°C and the stirring adsorption treatment time is 1-2h;

[0034] And / or, the mass ratio of the amount of the first adsorbent to the olive oil is (0.02-0.10):1.

[0035] Further, in step S5:

[0036] The stirring adsorption treatment temperature is 5-20°C and the time is 5-10h;

[0037] And / or, the mass ratio of the amount of the second adsorbent to the olive oil is (0.01-0.05):1.

[0038] Furthermore, both step S4 and step S5 are carried out by stirring and adsorption under vacuum conditions.

[0039] Furthermore, the step S1 and / or step S2 are performed in an inert atmosphere.

[0040] Another object of the present invention is to provide an olive oil obtained by the above-mentioned refining process, wherein the acid value is less than 0.1, the peroxide value is less than 1, and the free sterol content is less than 0.5%.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] The refining process of the present invention adopts the steps of alkali washing, water removal, adsorbent treatment and low-temperature treatment to refine olive oil, which can remove impurities that are difficult to remove by conventional oil refining methods and improve the quality of olive oil. Compared with the commonly used refining methods, the process is simple and easy to operate, the product quality is stable, and the industrial refining of medicinal olive oil has significant prospects.

[0043] The olive oil obtained by the refining process of the present invention is lighter yellow in color, and all indicators exceed the requirements of the standards, with an methoxyaniline value of less than 1, an acid value of less than 0.1, a peroxide value of less than 1, and a Δ7-stigmasterol content of less than 0.5%, which can fully meet the quality requirements of medicinal grade olive oil. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be clearly and completely described below in conjunction with the preferred embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0045] The following is a specific example. The activation method of the activated clay used in the example is to place the activated clay in a vacuum oven and heat it to 100-110°C, activate it for 30 minutes, and then cool it to room temperature. Unless otherwise specified, the materials or reagents used are commonly used in the field, and the experimental methods used are familiar to those skilled in the art.

[0046] Example 1

[0047] Step 1: Take 500g of olive oil, cool it to 5°C under nitrogen protection, keep it warm and stir it at a speed of 10r / min for 20h, then filter it and collect the filtrate;

[0048] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 55°C under nitrogen protection, then add 3.2g of a 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquids and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 8g of calcium chloride to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0049] Step 3: Take 350 g of the olive oil obtained in step 2, add 7 g of activated clay, heat to 70°C under vacuum, keep stirring for 1 hour, cool to room temperature, filter, and collect the filtrate;

[0050] Step 4: Take 300 g of the olive oil obtained in step 3, add 6 g of activated carbon, maintain stirring at 10°C for 8 hours under nitrogen protection, then filter, collect the filtrate, put it into a stainless steel bottle as required, and store it in nitrogen.

[0051] Example 2

[0052] Step 1: Take 500g of olive oil, cool it to 8°C under nitrogen protection, keep it warm and stir it at 8r / min for 15h, then filter it and collect the filtrate;

[0053] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 65°C under nitrogen protection, then add 3.6g of 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquid and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 12g of inactive alumina powder to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0054] Step 3: Take 350 g of the olive oil obtained in step 2, add 21 g of activated clay, heat to 75°C under vacuum, keep stirring for 1.5 hours, cool to room temperature, filter, and collect the filtrate;

[0055] Step 4: Take 300 g of the olive oil obtained in step 3, add 8 g of silica gel, maintain stirring at 8°C for 10 hours under nitrogen protection, then filter, collect the filtrate, put it into a brown glass bottle as required, and store it in nitrogen.

[0056] Example 3

[0057] Step 1: Take 500g of olive oil, cool it to 10°C under nitrogen protection, keep it warm and stir it at a speed of 15r / min for 18h, then filter it and collect the filtrate;

[0058] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 50°C under nitrogen protection, then add 4.0g of a 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquids and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 16g of molecular sieve activation powder to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0059] Step 3: Take 350 g of the olive oil obtained in step 2, add 35 g of activated clay, heat to 65° C. under vacuum, keep stirring for 1 hour, cool to room temperature, filter, and collect the filtrate;

[0060] Step 4: Take 300 g of the olive oil obtained in step 3, add 12 g of activated clay, maintain stirring at 12°C for 5 hours under nitrogen protection, then filter, collect the filtrate, put it into an aluminum bottle as required, and store it in nitrogen.

[0061] Example 4

[0062] Step 1: Take 500g of olive oil, cool it to 3°C under nitrogen protection, keep it warm and stir it at a speed of 12r / min for 25h, then filter it and collect the filtrate;

[0063] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 60°C under nitrogen protection, then add 3.6g of a 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquids and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 12g of dry molecular sieves to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0064] Step 3: Take 350 g of the olive oil obtained in step 2, add 28 g of activated clay, heat to 80° C. under vacuum, keep stirring for 1 hour, cool to room temperature, filter, and collect the filtrate;

[0065] Step 4: Take 300 g of the olive oil obtained in step 3, add 15 g of neutral alumina, maintain stirring at 15°C for 6 hours under nitrogen protection, then filter, collect the filtrate, put it into a blue high-density polyethylene bottle as required, and store it in nitrogen.

[0066] Example 5

[0067] Step 1: Take 500g of olive oil, cool it to 2°C under nitrogen protection, keep it warm and stir it at 8r / min for 16h, then filter it and collect the filtrate;

[0068] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 70°C under nitrogen protection, then add 4.4g of a 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquids and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 20g of silica-alumina gel to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0069] Step 3: Take 350 g of the olive oil obtained in step 2, add 14 g of activated activated clay, heat to 75° C. under vacuum, keep warm and stir for 1 hour, cool to room temperature, filter, and collect the filtrate;

[0070] Step 4: Take 300 g of the olive oil obtained in step 3, add 3 g of activated carbon and 3 g of activated clay, maintain stirring at 18 ° C for 8 hours under nitrogen protection, then filter, collect the filtrate, put it into an aluminum bottle as needed, and store it in nitrogen.

[0071] Example 6

[0072] Step 1: Take 500g of olive oil, cool it to 3°C under nitrogen protection, keep it warm and stir it at 5r / min for 18h, then filter and collect the filtrate;

[0073] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 65°C under nitrogen protection, then add 3.6g of 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquid and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 14g of water-resistant aluminum silica gel to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0074] Step 3: Take 350 g of the olive oil obtained in step 2, add 21 g of activated clay, heat to 60° C. under vacuum, keep warm and stir for 2 h, cool to room temperature, filter, and collect the filtrate;

[0075] Step 4: Take 300 g of the olive oil obtained in step 3, add 6 g of silica gel and 6 g of neutral alumina, stir at 10 °C for 10 h under nitrogen protection, then filter, collect the filtrate, put it into a stainless steel bottle as required, and store it in nitrogen.

[0076] Comparative Example 1 (Compared with Example 1, the order of activated clay adsorption treatment and alkali solution treatment was changed)

[0077] Step 1: Take 500g of olive oil, cool it to 3°C under nitrogen protection, keep it warm and stir it at a speed of 10r / min for 20h, then filter it and collect the filtrate;

[0078] Step 2: Take 400 g of the olive oil obtained in step 2, add 8 g of activated activated clay, heat to 70° C. under vacuum, keep warm and stir for 1 hour, cool to room temperature, filter, and collect the filtrate;

[0079] Step 3: Take 350g of the olive oil obtained in step 3, heat it to 55°C under nitrogen protection, then add 2.8g of a 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquids and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 8g of calcium chloride to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0080] Step 4: Take 300 g of the olive oil obtained in step 3, add 6 g of activated carbon, maintain stirring at 10°C for 10 h under nitrogen protection, then filter, collect the filtrate, put it into a stainless steel bottle as required, and store it in nitrogen.

[0081] Comparative Example 2 (Compared with Example 1, the order of step 3 and step 4 is changed)

[0082] Step 1: Take 500g of olive oil, cool it to 3°C under nitrogen protection, keep it warm and stir it at a speed of 10r / min for 20h, then filter it and collect the filtrate;

[0083] Step 2: Take 400g of the olive oil obtained in step 1, heat it to 5°C under nitrogen protection, then add 3.2g of a 5wt% sodium hydroxide solution, continue stirring for 30min, then let it stand for 1h, separate the liquids and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, add 8g of calcium chloride to the oil layer, stir for 30min, let it stand for 1h, and then collect the oil layer;

[0084] Step 3: Take 350 g of the olive oil obtained in step 2, add 7 g of activated carbon, maintain stirring at 10° C. for 8 h under nitrogen protection, then filter and collect the filtrate;

[0085] Step 4: Take 300 g of the olive oil obtained in step 3, add 6 g of activated activated clay, heat to 70°C under vacuum, keep stirring for 1 hour, cool to room temperature, filter, collect the filtrate, put it into a stainless steel bottle as needed, and store it in nitrogen.

[0086] Comparative Example 3 (Compared with Example 1, no dehydrating agent was used)

[0087] Step 1: Take 500g of olive oil, cool it to 5°C under nitrogen protection, keep it warm and stir it at a speed of 10r / min for 20h, then filter it and collect the filtrate;

[0088] Step 2: Take 400 g of the olive oil obtained in step 1, heat it to 55° C. under nitrogen protection, then add 3.2 g of a 5 wt % sodium hydroxide solution, continue stirring for 30 min, then let it stand for 1 h, separate the liquid and discard the lower water layer, wash the oil layer with water until the water layer is neutral, discard the water layer, and collect the oil layer;

[0089] Step 3: Take 350 g of the olive oil obtained in step 2, add 7 g of activated clay, heat to 70°C under vacuum, keep stirring for 1 hour, cool to room temperature, filter, and collect the filtrate;

[0090] Step 4: Take 300 g of the olive oil obtained in step 3, add 6 g of activated carbon, maintain stirring at 10°C for 8 hours under nitrogen protection, then filter, collect the filtrate, put it into a stainless steel bottle as required, and store it in nitrogen.

[0091] Relevant indexes of the refined olive oils obtained in Examples 1-6 and Comparative Examples 1-3 were tested, and the results are shown in Tables 1 and 2, respectively.

[0092] Table 1:

[0093]

[0094]

[0095] Table 2:

[0096]

[0097] It is not difficult to see from the test results in Table 1 that by refining olive oil using steps such as alkali washing, water removal, adsorbent treatment and low-temperature treatment, impurities that are difficult to remove by conventional oil refining methods can be removed, and the quality of olive oil can be significantly improved. The obtained olive oil is a lighter yellow color, and all indicators exceed the requirements of the standards, with an methoxyaniline value less than 1, an acid value less than 0.1, a peroxide value less than 1, and a Δ7-stigmasterol content less than 0.5%, which can fully meet the quality requirements of medicinal grade olive oil.

[0098] It is not difficult to see from the test results in Table 2 that the order of activated clay adsorption treatment and alkali solution treatment is changed in Comparative Example 1 relative to Example 1, resulting in an increase in the Δ7-stigmasterol content. The main reason is that sterols in olive oil exist in two states, one is free sterols and the other is sterol esters. Most of the sterols exist in the form of sterol esters, and a small part exists in the form of free sterols. However, free sterols are easier to be adsorbed and removed by the adsorbent than sterol esters. Alkaline washing is first used to hydrolyze sterol esters into free sterols, and then removed by the adsorbent. If the order is changed, the adsorbent simply adsorbs a small amount of free sterols, and the sterol esters are basically not reduced, resulting in an increase in the relative content of Δ7-stigmasterol in the refined olive oil.

[0099] Comparative Example 2: Changing the order of step 3 and step 4 relative to Example 1 will increase the Δ7-stigmasterol impurity content of the refined olive oil. The main reason is that β-sitosterol (content of about 80%) in sterols will be converted into a small amount of Δ7-stigmasterol under heating conditions (because the two are isomers). Therefore, the heating step should be placed in the front, and the subsequent low-temperature stirring will have the effect of reducing Δ7-stigmasterol; however, if the order is reversed, the content of Δ7-stigmasterol will increase;

[0100] In Comparative Example 3, the use of the dehydrating agent is removed in step 2 relative to Example 1, which will weaken the refining effect of the activated activated clay in step 3, resulting in the peroxide value, methoxyaniline value, color and other indicators in the refined olive oil being worse than those in Example 1. The effect of refining Δ7-stigmasterol will also deteriorate, and the adsorption of the impurity will not achieve the expected effect.

[0101] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for refining medicinal grade olive oil, characterized in that the steps include: S1. Slowly stir and filter the olive oil at low temperature; S2. After the filtered olive oil was heated and stirred, a sodium hydroxide solution was added and stirred, the upper layer was separated after standing, and the oil phase was washed with water to obtain an oil phase; S3. Add a dehydrating agent to the oil phase, dehydrate under stirring and let stand, collect the oil layer to obtain the oil phase II; S4. Add the first adsorbent to the oil phase II, adsorb under stirring, and filter to obtain the oil phase III; S5. Add the second adsorbent to the oil phase three, adsorb under stirring, and filter to obtain pharmaceutical grade olive oil; The first adsorbent is thermally activated activated clay; The second adsorbent is selected from at least one of activated clay, activated carbon, neutral alumina and silica gel.

2. The refining process according to claim 1, characterized in that: In step S1, the low temperature condition is 0-10°C, and the stirring treatment time is 15-25h; And / or, the stirring speed is 5-15 r / min.

3. The refining process according to claim 1, characterized in that: In step S2, the temperature is raised to 50-70°C; And / or, the concentration of the sodium hydroxide solution is 5wt%, and the mass ratio of the sodium hydroxide solution to the olive oil is (0.008-0.011):1; And / or, the standing time is 0.5-2h.

4. The refining process according to claim 1, characterized in that: In step S3, the dehydrating agent is selected from at least one of calcium chloride, activated alumina powder, molecular sieve activation powder, dry molecular sieve, silica alumina gel, and water-resistant aluminum silica gel; the mass ratio of the dehydrating agent to olive oil is (0.02-0.05):

1.

5. The refining process according to claim 1, characterized in that: The preparation process of the thermally activated activated clay is to heat the activated clay to 100-110° C. under vacuum, activate it for 30 minutes, and then cool it to obtain the thermally activated activated clay.

6. The refining process according to claim 1, characterized in that: In step S4, the adsorption condition is 60-80°C, and the stirring adsorption treatment time is 1-2h; And / or, the mass ratio of the amount of the first adsorbent to the olive oil is (0.02-0.10):

1.

7. The refining process according to claim 1, characterized in that: In step S5, the stirring adsorption treatment temperature is 5-20°C and the time is 5-10h; And / or, the mass ratio of the amount of the second adsorbent to the olive oil is (0.01-0.05):

1.

8. The refining process according to claim 1, characterized in that: The steps S4 and S5 are both performed under vacuum conditions for stirring and adsorption.

9. The refining process according to claim 1, characterized in that: The step S1 and / or step S2 are performed in an inert atmosphere.

10. The olive oil obtained by the refining process according to any one of claims 1 to 9, characterized in that: Its acid value is less than 0.1, its peroxide value is less than 1, and its free sterol content is less than 0.5%.

Images