Production process and application of micromolecular composite fully esterified pectin

Abstract

The invention relates to the technical field of full-esterified pectin production, and particularly discloses a production process and application of small-molecule composite full-esterified pectin, and the production process comprises the following steps: firstly, carrying out partial degreasing treatment on high-ester pectin by controlling reaction conditions; and then adding composite alcohol to control the reaction conditions to perform full esterification treatment on the residual carboxyl groups to form full esterification pectin in different proportions, and performing chain reduction, concentration and spray drying treatment on the formed full esterification pectin to obtain the micromolecular composite full esterification pectin. The micromolecular composite fully-esterified pectin is complete in esterification degree, rich in ester group variety, small in molecular chain and good in water solubility, and can be used as a natural plant preservative to be well applied to the fields of food, cosmetics and the like.

Description

Technical Field

[0001] The invention relates to the technical field of pectin production, and in particular to a production process and application of small-molecule composite fully esterified pectin. Background Art

[0002] Pectin is a polysaccharide that mainly exists in plant cell walls and cell inner layers, especially in the peels of citrus, lemons, grapefruits, etc. There are two main categories of commercial pectin: high-ester pectin and low-ester pectin. Amidated pectin also belongs to low-ester pectin. The main component of pectin is D-galacturonic acid, and many of the carboxyl groups on C6 exist in the form of methyl esterification. The ratio of esterified galacturonic acid to total galacturonic acid is called the degree of esterification. Generally, the highest degree of esterification of pectin extracted from natural raw materials is 75%. Pectin existing in nature is high-ester pectin, and low-ester pectin can be obtained by acid or alkali treatment. There are no relevant reports on fully esterified pectin.

[0003] Preservation is still one of the main research contents of the current food, cosmetics and other processing industries. Commonly used preservatives can be roughly divided into two categories according to their sources: chemical synthetic preservatives and natural preservatives. With the improvement of living standards, people's requirements for health are getting higher and higher. Although chemical preservatives have low costs and good preservative effects, they also have certain effects on human health. Natural preservatives, as a healthy, safe and effective preservative method, have received more and more attention and application. Natural preservatives mainly come from animals, plants and microorganisms. Plant natural preservatives have received more attention in the field of modern preservatives due to their advantages of health, safety, environmental protection and economy. Ester preservatives have the functions of penetrating cell walls, inhibiting respiration, affecting protein synthesis, etc., thereby achieving antibacterial and preservative effects. Small molecule composite fully esterified pectin not only comes from natural plants, but also has a composite full ester structure. The small molecule nature is more conducive to penetrating cell walls. Therefore, it can be used as a natural plant preservative in food, cosmetics and other fields. Summary of the invention

[0004] In order to solve the technical problems existing in the above-mentioned prior art, the present invention provides a production process and application of small molecule composite fully esterified pectin.

[0005] To achieve the above object, the present invention provides the following technical solution: a production process of small molecule composite fully esterified pectin, comprising the following steps:

[0006] S1. Deesterification of high-ester pectin is performed by controlling the reaction conditions. The purpose of partial deesterification of pectin is to retain a portion of methyl ester while exposing more carboxyl groups to react with other alcohols for esterification;

[0007] S2, adding complex alcohols to control the reaction conditions to fully esterify the remaining carboxyl groups to form fully esterified pectins in different proportions;

[0008] S3. The fully esterified pectin is subjected to chain reduction, concentration and spray drying treatment to obtain small molecule composite fully esterified pectin.

[0009] Preferably, in S1, the high-ester pectin is derived from one or more of citrus, lemon, apple and grapefruit.

[0010] Preferably, the high ester pectin is partially defatted by an alkali method, and the alkali used is one or more of sodium carbonate, sodium bicarbonate and sodium hydroxide.

[0011] Preferably, the pH of alkaline deesterification is 8-10, the time is 2-10h, the temperature is 10-30°C, and the degree of esterification after degreasing is ≥30. In addition, since fully esterified pectin is a combination of different esters, a portion of methyl esters needs to be retained after degreasing, and the degree of esterification after degreasing is ≥30, which is easy to achieve, so the degree of esterification after degreasing is ≥30.

[0012] Preferably, in S2, the alcohol substance added is one or more of ethanol and propanol.

[0013] Preferably, the full esterification reaction temperature is 60-70°C and the pressure is 0.3-0.5Mpa.

[0014] Preferably, the ratio of deesterified pectin to alcohol substance is 1:1-10.

[0015] Preferably, in S3, the fully esterified pectin is degraded by hydrogen peroxide method, the amount of hydrogen peroxide added is 5-20% of the system, the degradation time is 5-10 hours, and the temperature is 5-40°C.

[0016] Preferably, the degraded fully esterified pectin is treated with catalase to remove excess hydrogen peroxide.

[0017] In addition, the present invention also provides a small molecule composite fully esterified pectin prepared by the above process, and the small molecule composite fully esterified pectin is used in the preparation of a natural plant preservative.

[0018] Compared with the prior art, the present invention provides a production process and application of small molecule composite fully esterified pectin, which has the following beneficial effects:

[0019] The raw materials in the present invention are derived from high-fat pectin extracted from natural citrus, lemon, apple, grapefruit, etc., which are natural and healthy. By controlling the deesterification and performing a full esterification reaction with complex alcohols, fully esterified pectin with different esterification distribution ratios can be obtained. The ester preservatives have the functions of penetrating cell walls, inhibiting respiration, affecting protein synthesis, etc., thereby achieving antibacterial and antiseptic effects. The presence of rich esters helps to have an antibacterial and antiseptic effect on multiple bacterial species. Making them into small molecules is more conducive to penetrating the cell wall.

[0020] The obtained fully esterified pectin can be used in the ranks of natural plant preservatives and has good applications in the fields of food, cosmetics, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the result of the antibacterial test on Escherichia coli using high-fat pectin extracted from citrus;

[0022] Figure 2 This is a graph showing the results of an antibacterial test on Escherichia coli using Example 4. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0024] The present invention provides a production process of small molecule composite fully esterified pectin, which specifically comprises the following steps:

[0025] S1. Deesterification of high-ester pectin is performed by controlling the reaction conditions. The purpose of partial deesterification of pectin is to retain a portion of methyl ester while exposing more carboxyl groups to react with other alcohols for esterification;

[0026] S2, adding complex alcohols to control the reaction conditions to fully esterify the remaining carboxyl groups to form fully esterified pectins in different proportions;

[0027] S3. The fully esterified pectin is subjected to chain reduction, concentration and spray drying treatment to obtain small molecule composite fully esterified pectin.

[0028] In the present invention, the high-ester pectin is derived from one or more of citrus, lemon, apple and grapefruit.

[0029] In the present invention, the high ester pectin is partially defatted by an alkali method, wherein the alkali used is one or more of sodium carbonate, sodium bicarbonate and sodium hydroxide.

[0030] In the present invention, the pH of alkaline deesterification is 8-10, the time is 2-10h, the temperature is 10-30°C, and the esterification degree after degreasing is ≥30. It should be pointed out that when the time is controlled at 5h and the temperature is 20°C, the esterification degree is higher when the pH is 8-10; when the pH is 9, the time is controlled at 5h and the temperature is 10-30°C, the esterification degree is higher; when the pH is 9 and the temperature is 20°C, the esterification degree is higher when the time is 2-10h; in addition, since fully esterified pectin is a combination of different esters, a part of methyl ester needs to be retained after degreasing, and the esterification degree after degreasing is ≥30, which is easy to achieve, so the esterification degree after degreasing is ≥30.

[0031] In the present invention, the alcohol substance added is one or more of ethanol and propanol. The full esterification reaction temperature is 60-70°C and the pressure is 0.3-0.5Mpa. The full esterification reaction temperature is controlled to be 65°C and the pressure is preferably 0.3-0.5Mpa; the pressure is controlled to be 0.4Mpa and the reaction temperature is preferably 60-70°C. The ratio of deesterified pectin to alcohol substance is 1:1-10.

[0032] In the present invention, a hydrogen peroxide method is adopted to degrade fully esterified pectin, the amount of hydrogen peroxide added is 5-20% of the system, the degradation time is 5-10 hours, the temperature is 5-40°C, the amount of hydrogen peroxide added is controlled to be 13%, the degradation time is 8 hours, and the temperature is preferably 5-40°C; the amount of hydrogen peroxide added is controlled to be 13%, the temperature is 25°C, and the degradation time is preferably 5-10 hours; the degradation time is controlled to be 8 hours, the temperature is 25°C, and the amount of hydrogen peroxide added is preferably 5-20%.

[0033] In the present invention, the excess hydrogen peroxide is treated with catalase in the fully esterified pectin after degradation.

[0034] It should be noted that the following embodiments and features in the embodiments may be combined with each other in the absence of conflict; and, based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without making any creative work are within the scope of protection of the present disclosure.

[0035] Various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein may be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this disclosure, it should be understood by those skilled in the art that an aspect described herein may be implemented independently of any other aspect, and two or more of these aspects may be combined in various ways. For example, any number of aspects described herein may be used to implement a device and / or practice a method. In addition, other structures and / or functionality other than one or more of the aspects described herein may be used to implement this device and / or practice this method.

[0036] Embodiment 1

[0037] The production process of small molecule composite fully esterified pectin is as follows:

[0038] (1) 100 kg of high-fat pectin extracted from citrus was deesterified, and the pH was adjusted to 9 with sodium carbonate and sodium hydroxide. The reaction time was 8 hours and the reaction temperature was 15°C.

[0039] (2) Add the deesterified pectin into ethanol solvent at a ratio of 1:5 to carry out full esterification reaction at a reaction temperature of 65°C and a pressure of 0.3 MPa.

[0040] (3) The obtained fully esterified pectin was degraded with hydrogen peroxide, the ratio of hydrogen peroxide added was 10% of the system, the degradation time was 7 hours, and the temperature was 20°C.

[0041] (4) The degraded fully esterified pectin is treated with catalase to remove excess hydrogen peroxide, and then concentrated and spray-dried to obtain methyl ester and ethyl ester fully esterified pectin (methyl ester: ethyl ester = 4:6), the structural formula of which is as follows:

[0042]

[0044] Embodiment 2

[0045] The production process of small molecule composite fully esterified pectin is as follows:

[0046] (1) 100 kg of high-fat pectin extracted from citrus was deesterified by adjusting the pH to 10 with sodium bicarbonate and sodium hydroxide, the reaction time was 6 hours, and the reaction temperature was 25°C.

[0047] (2) Add the deesterified pectin into propanol solvent at a ratio of 1:4 to carry out full esterification reaction at a reaction temperature of 67°C and a pressure of 0.4 MPa.

[0048] (3) The obtained fully esterified pectin was degraded with hydrogen peroxide, the ratio of hydrogen peroxide added was 10% of the system, the degradation time was 6 hours, and the temperature was 15°C.

[0049] (4) The degraded fully esterified pectin is treated with catalase to remove excess hydrogen peroxide, and then concentrated and spray-dried to obtain methyl ester and propyl ester fully esterified pectin (methyl ester: propyl ester = 4.5:5.5), the structural formula of which is as follows:

[0050]

[0051] Embodiment 3

[0052] The production process and application of small molecule composite fully esterified pectin are as follows:

[0053] (1) 100 kg of high-fat pectin extracted from lemon was deesterified, and the pH was adjusted to 8.5 with sodium bicarbonate and sodium hydroxide. The reaction time was 10 hours and the reaction temperature was 25°C.

[0054] (2) Add the deesterified pectin to ethanol and propanol solvents in a ratio of 1:5:3 to carry out a full esterification reaction at a reaction temperature of 70°C and a pressure of 0.5 MPa.

[0055] (3) The fully esterified pectin was degraded with hydrogen peroxide, the ratio of hydrogen peroxide added was 10% of the system, the degradation time was 7 hours, and the temperature was 25°C.

[0056] (4) The degraded fully esterified pectin is treated with catalase to remove excess hydrogen peroxide, and then concentrated and spray-dried to obtain methyl ester, ethyl ester, and propyl ester fully esterified pectin (methyl ester: ethyl ester: propyl ester = 4.5:3.5:2), the structural formula of which is as follows:

[0057]

[0058] Embodiment 4

[0059] The production process of small molecule composite fully esterified pectin is as follows:

[0060] (1) 100 kg of high-fat pectin extracted from lemon was deesterified, and the pH was adjusted to 9.5 with sodium carbonate and sodium hydroxide. The reaction time was 9 hours and the reaction temperature was 10°C.

[0061] (2) Add the deesterified pectin to ethanol and propanol solvents in a ratio of 1:1:2 to carry out a full esterification reaction at a reaction temperature of 65°C and a pressure of 0.5 MPa.

[0062] (3) The obtained fully esterified pectin was degraded with hydrogen peroxide, the ratio of added hydrogen peroxide was 10% of the system, the degradation time was 8 hours, and the temperature was 30°C.

[0063] (4) The degraded fully esterified pectin is treated with catalase to remove excess hydrogen peroxide, and then concentrated and spray-dried to obtain methyl ester, ethyl ester, and propyl ester fully esterified pectin (methyl ester: ethyl ester: propyl ester = 4.5:2.5:3), the structural formula of which is as follows:

[0064]

[0065] The present invention also conducts an E. coli antibacterial test on the product in Example 4 and high-fat pectin extracted from citrus. The specific experimental process is as follows:

[0066] (1) Use an inoculating loop to pick up the bacteria on the slope of the test tube and place it in sterile water with glass beads. Shake it by hand for several minutes to disperse the spores. Filter it to make a mixed spore suspension.

[0067] (2) Use a sterile pipette to inject 0.5 mL of a mixed spore suspension of a certain concentration into each culture dish.

[0068] (3) Pour 15 ml to 20 ml of molten agar medium (about 45°C) into each culture dish, mix the bacterial solution and the medium evenly, and wait for them to cool.

[0069] (4) Use tweezers to immerse the disc of filter paper in different concentrations of fully esterified pectin for a while, take it out and place it in the center of the bacterial culture medium plate, and cover it with a lid.

[0070] (5) Incubate at an appropriate temperature for 2 to 3 days and observe the presence and size of the inhibition zone around the filter paper disc.

[0071] from Figure 1 It can be seen that for high-fat pectin extracted from citrus, no inhibition zone was shown in the concentration range of 0.31 mg / mL-10.00 mg / mL. Figure 2 The results show that the sample concentration and the corresponding antibacterial zone diameter are: 2.50mg / mL-8mm, 5.00mg / mL-12mm, 10.00mg / mL-15mm; as the concentration increases, the diameter of the antibacterial zone increases. It can be concluded that Example 4 has a good antibacterial effect on Escherichia coli, indicating that fully esterified pectin has certain advantages over high-fat pectin in antibacterial and antiseptic properties.

[0072] Although the 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 claims and their equivalents.

Claims

1. A production process of small molecule composite fully esterified pectin, characterized in that: The steps include: S1. Deesterification of high ester pectin by controlling reaction conditions; S2, adding complex alcohols to control the reaction conditions to fully esterify the remaining carboxyl groups to form fully esterified pectins in different proportions; S3. The fully esterified pectin is subjected to chain reduction, concentration and spray drying treatment to obtain small molecule composite fully esterified pectin.

2. The production process of a small molecule composite fully esterified pectin according to claim 1, characterized in that: In S1, the high ester pectin is derived from one or more of citrus, lemon, apple, and grapefruit.

3. The production process of a small molecule composite fully esterified pectin according to claim 1 or 2, characterized in that: The high ester pectin is partially defatted by an alkali method, and the alkali used is one or more of sodium carbonate, sodium bicarbonate and sodium hydroxide.

4. The production process of a small molecule composite fully esterified pectin according to claim 3, characterized in that: The pH of alkaline deesterification is 8-10, the time is 2-10h, the temperature is 10-30℃, and the esterification degree after degreasing is ≥30.

5. The production process of a small molecule composite fully esterified pectin according to claim 1, characterized in that: In S2, the alcohol substance added is one or more of ethanol and propanol.

6. The production process of a small molecule composite fully esterified pectin according to claim 5, characterized in that: The full esterification reaction temperature is 60-70°C and the pressure is 0.3-0.5Mpa.

7. The production process of a small molecule composite fully esterified pectin according to claim 5 or 6, characterized in that: The ratio of deesterified pectin to alcohol substances is 1:1-10.

8. The production process of a small molecule composite fully esterified pectin according to claim 5 or 6, characterized in that: In S3, the fully esterified pectin is degraded by hydrogen peroxide method, the amount of hydrogen peroxide added is 5-20% of the system, the degradation time is 5-10 hours, and the temperature is 5-40°C.

9. The production process of a small molecule composite fully esterified pectin according to claim 8, characterized in that: After degradation, the fully esterified pectin was treated with catalase to remove excess hydrogen peroxide.

10. A small molecule composite fully esterified pectin, characterized in that: The small molecule composite fully esterified pectin is prepared by the production process described in any one of claims 1 to 9 and is used in the preparation of natural plant preservatives.

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