Iron-based deoxidizer, method for preparing the same, and use thereof

Abstract

The present application relates to the field of food processing and packaging technology, and more particularly to a deoxidizer, and more particularly to an iron-based deoxidizer capable of deoxidation, dehumidification and drying, and a preparation method and application thereof. The present application provides an iron-based deoxidizer, a preparation method and application thereof. The preparation raw materials of the iron-based deoxidizer include 60-80 wt.% of iron powder, 3-30 wt.% of anhydrous sodium sulfate, 0.2-10.0 wt.% of sodium bromide, 0.1-3.0 wt.% of activated carbon and 1.0-5.0 wt.% of glycerol aqueous solution. The iron-based deoxidizer can not only effectively remove oxygen but also dehumidify and dry the external environment, which is conducive to its popularization and application in the field of food or medicine (such as nuts, roasted seeds and nuts and puffed food and medicine) that needs to be dried.

Description

Technical Field

[0001] This invention relates to the field of food processing and packaging technology, and more particularly to a deoxidizer, and even more particularly to an iron-based deoxidizer capable of deoxidation, dehumidification, and drying, as well as its preparation method and application. Background Technology

[0002] Oxygen absorbers are additives that absorb oxygen and slow down the oxidation of food. They can effectively inhibit the growth of mold and aerobic bacteria, extend the shelf life of food, and also play a good role in preventing rancidity of oils, oxidative browning of meat, and loss of vitamins in food.

[0003] Commonly used deoxidizers include iron powder oxidation (iron-based), enzyme oxidation (enzyme-based), ascorbic acid oxidation, and photosensitive dye oxidation. Most deoxidizers currently in use are based on iron powder oxidation. These iron-based deoxidizers can be packaged in bags to reduce the oxygen concentration to 0.01%. The main raw materials of iron-based deoxidizers are iron powder, activated carbon, sodium chloride, water-absorbing resin, silica, diatomaceous earth, vermiculite, and water. Iron-based deoxidizers require sufficient moisture for a complete reaction, with a moisture content primarily between 8% and 16%. However, when used in foods or pharmaceuticals requiring drying, moisture transfer easily occurs. This transferred moisture can cause the food or pharmaceuticals to become damp, ultimately affecting their quality. Reducing the moisture content of the deoxidizer to avoid affecting the quality of the food or pharmaceuticals results in ineffective oxygen removal. Therefore, iron-based deoxidizers have long been limited in their application to foods or pharmaceuticals requiring drying, severely restricting their use in nuts, roasted seeds, puffed foods, and pharmaceuticals. Summary of the Invention

[0004] In view of the above problems, the present invention provides an iron-based deoxidizer, its preparation method and application. The iron-based deoxidizer can not only effectively remove oxygen, but also dehumidify and dry the external environment, which can facilitate its application in the fields of food or medicine that require drying (such as nuts, roasted seeds and puffed foods and medicines).

[0005] To achieve the above objectives, the present invention provides an iron-based deoxidizer. The raw materials for preparing the iron-based deoxidizer include 60–80 wt.% iron powder, 3–30 wt.% anhydrous sodium sulfate, 0.2–10.0 wt.% sodium bromide, 0.1–3.0 wt.% activated carbon, and 1.0–5.0 wt.% an aqueous solution of glycerol.

[0006] In the preparation of the iron-based deoxidizer of this invention, activated carbon can enrich oxygen and promote the reaction between iron powder and oxygen. Glycerin aqueous solution can act as a solvent to dissolve anhydrous sodium sulfate and sodium bromide. Simultaneously, glycerin effectively locks in moisture to prevent its transfer into food or pharmaceuticals, thus avoiding moisture absorption and affecting the quality of the food or pharmaceuticals. Sodium bromide, as a desiccant, oxygen-absorbing catalyst, and crystal water promoter, can absorb external moisture, promote the reaction between iron powder and oxygen, and also promote the dissolution of sodium sulfate decahydrate and the release of its contained crystal water. Anhydrous sodium sulfate, as a desiccant, can effectively absorb external moisture and form crystal hydrates, storing the absorbed water chemically within its structure. After absorbing water, it can form sodium sulfate decahydrate. When the iron-based deoxidizer comes into contact with oxygen, the iron powder reacts with oxygen and water, disrupting the dynamic equilibrium of water. The water of crystallization of sodium sulfate decahydrate continuously dissolves and releases water under the action of sodium bromide. This dissolved water then dissolves in glycerol and permeates into the iron powder to participate in the deoxidation reaction. When the iron powder stops reacting, the dissolved water reaches a new equilibrium. At this point, anhydrous sodium sulfate continuously absorbs water from the environment and transforms into sodium sulfate decahydrate. In other words, the sodium bromide and anhydrous sodium sulfate in the iron-based deoxidizer of this invention can adsorb water from the environment to achieve dehumidification and drying. The sodium sulfate decahydrate generated by sodium sulfate absorbing water can provide more water for the deoxidation reaction of reduced iron after dissolution and transformation. Glycerol can effectively lock in the water in the system to prevent it from transferring to food or pharmaceuticals, thus avoiding moisture absorption and affecting the quality of the food or pharmaceuticals. This is beneficial for its widespread application in the fields of food or pharmaceuticals requiring drying (such as nuts, roasted seeds, puffed foods, and medicines).

[0007] Preferably, the raw materials for preparing the iron-based deoxidizer include 65-75 wt.% iron powder, 10-25 wt.% anhydrous sodium sulfate, 1.0-5.0 wt.% sodium bromide, 0.5-1.5 wt.% activated carbon, and 3.0-5.0 wt.% aqueous glycerol solution.

[0008] Preferably, the concentration of the glycerol aqueous solution in the iron-based deoxidizer is 0.5–4.5 wt.%.

[0009] Preferably, the mass of the iron-based deoxidizer is 1.5–2.5 g.

[0010] Another aspect of the present invention provides a method for preparing an iron-based deoxidizer, comprising the steps of:

[0011] (1) Add glycerol to water to prepare the glycerol aqueous solution;

[0012] (2) Mix the iron powder and the activated carbon and stir them, then add the glycerol aqueous solution while stirring and mix.

[0013] (3) Add the anhydrous sodium sulfate and the sodium bromide, mix and then seal and package.

[0014] In the preparation method of the iron-based deoxidizer of the present invention, glycerol is made into an aqueous glycerol solution, which has a certain viscosity. When mixed with iron powder and activated carbon, it can combine the iron powder and activated carbon together to reduce dust generated during the preparation process and has good flowability. At the same time, glycerol can be adsorbed on the surface of iron powder and can also provide the iron powder with the water required for the reaction with oxygen. When anhydrous sodium sulfate and sodium bromide are added, the anhydrous sodium sulfate and sodium bromide will dissolve to a certain extent after contacting the aqueous glycerol solution and mix together with the iron powder and activated carbon, while still maintaining good flowability. In addition, the anhydrous sodium sulfate and sodium bromide will dissolve to a certain extent after contacting the aqueous glycerol solution. The dissolution will reach an equilibrium and no longer dissolve. During this process, a small amount of anhydrous sodium sulfate is converted into sodium sulfate decahydrate and can maintain its water absorption function. The water of crystallization in sodium sulfate decahydrate is stored in the material structure and can be released later for use by the iron powder reaction.

[0015] Preferably, the encapsulation is performed in a breathable packaging film.

[0016] Preferably, the breathable packaging film is sealed on three sides.

[0017] In another aspect, the present invention provides the application of the aforementioned iron-based deoxidizer or the iron-based deoxidizer prepared by the aforementioned method for deoxidation, dehumidification, and drying of food or pharmaceuticals.

[0018] Preferably, the iron-based deoxidizer is sealed together with the food or medicine in the packaging. Detailed Implementation

[0019] The iron-based deoxidizer of this invention can be used for deoxidation and dehumidification drying of foods such as nuts, roasted seeds, and puffed products, as well as pharmaceuticals. During manufacturing, it can be sealed in packaging along with the food or pharmaceutical. For example, it can be sealed in a packaging bag along with the food, or sealed in a packaging box along with the pharmaceutical.

[0020] The raw materials for preparing the iron-based deoxidizer of this invention include 60-80 wt.% iron powder, 3-30 wt.% anhydrous sodium sulfate, 0.2-10.0 wt.% sodium bromide, 0.1-3.0 wt.% activated carbon, and 1.0-5.0 wt.% an aqueous glycerol solution. Further, the raw materials for preparing the iron-based deoxidizer include 65-75 wt.% iron powder, 10-25 wt.% anhydrous sodium sulfate, 1.0-5.0 wt.% sodium bromide, 0.5-1.5 wt.% activated carbon, and 3.0-5.0 wt.% an aqueous glycerol solution. As an example, the content of iron powder may be, but is not limited to, 60 wt.%, 62 wt.%, 64 wt.%, 66 wt.%, 68 wt.%, 70 wt.%, 72 wt.%, 74 wt.%, 76 wt.%, 78 wt.%, and 80 wt.%. The content of anhydrous sodium sulfate may be, but is not limited to, 3 wt.%, 7 wt.%, 10 wt.%, 12 wt.%, 15 wt.%, 17 wt.%, 20 wt.%, 22 wt.%, 24 wt.%, 26 wt.%, 28 wt.%, and 30 wt.%. The content of sodium bromide may be, but is not limited to, 0.2 wt.%, 0.5 wt.%, 1.0 wt.%, 2.0 wt.%, 3.0 wt.%, 4.0 wt.%, 5.0 wt.%, 6.0 wt.%, 7.0 wt.%, 8.0 wt.%, 9.0 wt.%, and 10.0 wt.%. The content of activated carbon may be, but is not limited to, 0.1 wt.%, 0.3 wt.%, 0.5 wt.%, 0.7 wt.%, 0.9 wt.%, 1.0 wt.%, 1.5 wt.%, 2.0 wt.%, 2.5 wt.%, and 3.0 wt.%. The content of the glycerol aqueous solution may be, but is not limited to, 1.0 wt.%, 2.0 wt.%, 3.0 wt.%, 4.0 wt.%, and 5.0 wt.%.

[0021] The concentration of the glycerol aqueous solution is 0.5–4.5 wt.%, and for example, the concentration may be, but is not limited to, 0.5 wt.%, 1.0 wt.%, 1.5 wt.%, 2.0 wt.%, 2.5 wt.%, 3.0 wt.%, 3.5 wt.%, 4.0 wt.%, and 4.5 wt.%. The mass of the iron-based deoxidizer is 1.5–2.5 g, and for example, the mass may be, but is not limited to, 1.5 g, 1.7 g, 1.9 g, 2.1 g, 2.3 g, and 2.5 g.

[0022] The preparation method of the iron-based deoxidizer of the present invention includes the following steps: (1) adding glycerol to water to prepare the glycerol aqueous solution; (2) mixing iron powder and activated carbon and stirring, and adding the glycerol aqueous solution while stirring; (3) adding anhydrous sodium sulfate and sodium bromide, mixing, and then sealing and dispensing.

[0023] During packaging, the mixed raw materials are encapsulated in a breathable packaging film, and the breathable packaging film is three-sided sealed, with the encapsulated size being 4×4cm.

[0024] To better illustrate the purpose, technical solution, and beneficial effects of this invention, the invention will be further described below with reference to specific embodiments. It should be noted that the methods described below are further explanations of this invention and should not be construed as limiting it.

[0025] Example 1

[0026] This embodiment is an iron-based deoxidizer, and its raw materials include 72.5 wt.% iron powder, 20 wt.% anhydrous sodium sulfate, 3.0 wt.% sodium bromide, 1.5 wt.% activated carbon and 3.0 wt.% glycerol aqueous solution.

[0027] Its preparation method includes the following steps:

[0028] (1) Add glycerol to water to prepare a glycerol aqueous solution with a concentration of 3.5 wt.%;

[0029] (2) Mix the iron powder and activated carbon according to the formula and stir. Add the glycerol aqueous solution while stirring and mix.

[0030] (3) After adding anhydrous sodium sulfate and sodium bromide and mixing, take 2g of each and seal them on three sides through a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0031] Example 2

[0032] This embodiment is an iron-based deoxidizer, and its raw materials include 75.5 wt.% iron powder, 16 wt.% anhydrous sodium sulfate, 3.2 wt.% sodium bromide, 0.8 wt.% activated carbon and 4.5 wt.% glycerol aqueous solution.

[0033] Its preparation method includes the following steps:

[0034] (1) Add glycerol to water to prepare a glycerol aqueous solution with a concentration of 3.5 wt.%;

[0035] (2) Mix the iron powder and activated carbon according to the formula and stir. Add the glycerol aqueous solution while stirring and mix.

[0036] (3) After adding anhydrous sodium sulfate and sodium bromide and mixing, take 2g of each and seal them on three sides through a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0037] Example 3

[0038] This embodiment is an iron-based deoxidizer, and its raw materials include 65.7 wt.% iron powder, 25 wt.% anhydrous sodium sulfate, 3.6 wt.% sodium bromide, 1.4 wt.% activated carbon and 4.3 wt.% glycerol aqueous solution.

[0039] Its preparation method includes the following steps:

[0040] (1) Add glycerol to water to prepare a glycerol aqueous solution with a concentration of 4.3 wt.%;

[0041] (2) Mix the iron powder and activated carbon according to the formula and stir. Add the glycerol aqueous solution while stirring and mix.

[0042] (3) After adding anhydrous sodium sulfate and sodium bromide and mixing, take 2g of each and seal them on three sides through a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0043] Comparative Example 1

[0044] This embodiment is an iron-based deoxidizer, and its raw materials include 92.5 wt.% iron powder, 3.0 wt.% sodium bromide, 1.5 wt.% activated carbon and 3.0 wt.% glycerol aqueous solution.

[0045] Its preparation method includes the following steps:

[0046] (1) Add glycerol to water to prepare a glycerol aqueous solution with a concentration of 3.5 wt.%;

[0047] (2) Mix the iron powder and activated carbon according to the formula and stir. Add the glycerol aqueous solution while stirring and mix.

[0048] (3) After adding sodium bromide and mixing, take 2g of each and seal them on three sides through a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0049] Comparative Example 2

[0050] This embodiment is an iron-based deoxidizer, and its raw materials include 75.5 wt.% iron powder, 20 wt.% anhydrous sodium sulfate, 1.5 wt.% activated carbon and 3.0 wt.% glycerol aqueous solution.

[0051] Its preparation method includes the following steps:

[0052] (1) Add glycerol to water to prepare a glycerol aqueous solution with a concentration of 3.5 wt.%;

[0053] (2) Mix the iron powder and activated carbon according to the formula and stir. Add the glycerol aqueous solution while stirring and mix.

[0054] (3) After adding anhydrous sodium sulfate and mixing, take 2g of each and seal them on three sides using a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0055] Comparative Example 3

[0056] This embodiment is an iron-based deoxidizer, and its raw materials include 74.0 wt.% iron powder, 20 wt.% anhydrous sodium sulfate, 3.0 wt.% sodium bromide and 3.0 wt.% glycerol aqueous solution.

[0057] Its preparation method includes the following steps:

[0058] (1) Add glycerol to water to prepare a glycerol aqueous solution with a concentration of 3.5 wt.%;

[0059] (2) Mix the iron powder of the specified amount and stir, then add the glycerol aqueous solution while stirring and mix.

[0060] (3) After adding anhydrous sodium sulfate and sodium bromide and mixing, take 2g of each and seal them on three sides through a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0061] Comparative Example 4

[0062] This embodiment is an iron-based deoxidizer, and its raw materials include 72.5 wt.% iron powder, 20 wt.% anhydrous sodium sulfate, 3.0 wt.% sodium bromide, 1.5 wt.% activated carbon and 3.0 wt.% water.

[0063] Its preparation method includes the following steps:

[0064] (1) Mix the iron powder and activated carbon according to the formula and stir, then add water while stirring;

[0065] (2) After adding anhydrous sodium sulfate and sodium bromide and mixing, take 2g of each and seal them on three sides through a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0066] Comparative Example 5

[0067] This embodiment is an iron-based deoxidizer, and its raw materials include 75.0 wt.% iron powder, 5.0 wt.% water-absorbing resin, 3.0 wt.% diatomaceous earth, 1.0 wt.% vermiculite, 15 wt.% sodium chloride solution with a concentration of 13.0 wt.% and 1.0 wt.% activated carbon.

[0068] Its preparation method includes the following steps:

[0069] (1) Mix iron powder, water-absorbing resin, diatomaceous earth, vermiculite and activated carbon evenly to obtain a mixture;

[0070] (2) Add sodium chloride solution to the mixture and stir evenly. Take 2g of each sample and seal it on three sides using a breathable film and packaging equipment to obtain multiple deoxidizer samples with a sample size of 4×4cm.

[0071] The iron-based deoxidizers of Examples 1-2 and Comparative Examples 1-5 were tested for deoxidation and dehumidification properties. The test results are shown in Table 1.

[0072] Test procedure: At 25℃, 300mL of air was filled into each of the same size packaging bags, and the relative humidity of the packaging bags was adjusted to 30%, 40%, 60%, and 80% respectively. One iron-based deoxidizer of Examples 1-2 and Comparative Examples 1-5 was placed in each packaging bag and sealed. The oxygen concentration and relative humidity in the packaging bags were measured every 24 hours. Three equilibrium samples were made at each relative humidity and the average value was taken (that is, 12 deoxidizer samples were required for testing of the iron-based deoxidizers of Examples 1-2 and Comparative Examples 1-5).

[0073] Table 1. Deoxidation and dehumidification performance tests of iron-based deoxidizers in Examples 1-2 and Comparative Examples 1-5.

[0074]

[0075]

[0076] As shown in Table 1, the iron-based deoxidizers in Examples 1 and 2 can effectively remove oxygen in packages with different relative humidity levels, and the deoxidation speed is fast, with the oxygen concentration reaching 0.000% after 1 day of treatment. Simultaneously, the relative humidity decreased significantly after treatment, indicating that the iron-based deoxidizers in Examples 1 and 2 do not transfer moisture to the outside environment while absorbing oxygen, and can absorb external moisture simultaneously, achieving the dual effects of oxygen absorption, dehumidification, and drying.

[0077] Comparative Example 1 failed to completely remove oxygen from the packaging bag at a relative humidity of 30%. This was mainly because Comparative Example 1 lacked anhydrous sodium sulfate, which could not replenish the moisture required for the reaction. Therefore, at the low moisture content of 30% relative humidity, there was insufficient water for the deoxygenation reaction. However, it effectively removed oxygen at other relative humidity levels. At a relative humidity of 80%, the relative humidity decreased slightly after deoxygenation in the packaging bag. This was mainly due to sodium bromide absorbing external moisture, leading to a slight decrease in the relative humidity inside the packaging. In packaging bags with a relative humidity ≤60%, the relative humidity increased after deoxygenation, indicating that iron-based deoxidizers transferred moisture to the outside after deoxygenation, causing the relative humidity inside the packaging to rise. Sodium bromide could not absorb external moisture within this relative humidity range and therefore did not achieve a dehumidification effect.

[0078] In Comparative Example 2, the iron-based deoxidizer had a high concentration of oxygen inside the packaging bag under different humidity conditions, while the relative humidity effectively decreased. This indicates that the lack of sodium bromide will significantly inhibit the reaction between iron powder and oxygen, and the decrease in relative humidity is due to the good water absorption effect of anhydrous sodium sulfate.

[0079] In Comparative Example 3, the iron-based deoxidizer lacked activated carbon, resulting in a slow oxidation reaction of the iron powder. Only the packaged product with a relative humidity of 80% was able to effectively remove oxygen on the third day. The other packages were not able to effectively remove oxygen, but the relative humidity inside the packages decreased, indicating that the iron-based deoxidizer has a hygroscopic effect.

[0080] In Comparative Example 4, without glycerin to retain moisture, the deoxygenator lost moisture quickly in an environment with a relative humidity of less than 40%, and failed to effectively remove oxygen in the packaging at relative humidity of 30% and 40%; the deoxygenation speed in the packaging at 60% relative humidity was relatively slow, indicating that the lack of glycerin in the formula would result in a poorer water retention effect.

[0081] Although the iron-based deoxidizer in Comparative Example 5 could remove all oxygen, the relative humidity increased significantly, indicating that a large amount of moisture was transferred out of the iron-based deoxidizer. This is mainly because the water-absorbing resin, diatomaceous earth, and vermiculite materials absorb moisture physically, and it is easy to transfer out in an environment with low relative humidity. At the same time, the heat released by the reaction of iron powder with oxygen will accelerate the transfer of moisture from the iron-based deoxidizer.

[0082] The iron-based deoxidizer from Example 3 and 130g of roasted sunflower seeds (moisture content 2.43%, relative humidity 27.6%) were sealed together in a package. The oxygen concentration and relative humidity inside the package were measured every 24 hours, and the results are shown in Table 2.

[0083] Table 2. Deoxidation and dehumidification applicability tests of the iron-based deoxidizer in Example 3.

[0084]

[0085]

[0086] As shown in Table 2, the iron-based deoxidizer can effectively remove oxygen in roasted sunflower seeds. The relative humidity inside the packaging bag remains basically unchanged, and the moisture content of the sunflower seeds remains basically unchanged. This indicates that the iron-based deoxidizer of the present invention can also effectively remove oxygen in sunflower seeds dried with low moisture content, and the moisture will not transfer to the sunflower seeds. It can achieve the dual effects of deoxygenation, dehumidification, and drying.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. The application of an iron-based deoxidizer in the deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The raw materials for preparing the iron-based deoxidizer are 60-80 wt.% iron powder, 3-30 wt.% anhydrous sodium sulfate, 0.2-10.0 wt.% sodium bromide, 0.1-3.0 wt.% activated carbon, and 1.0-5.0 wt.% glycerol aqueous solution.

2. The application of the iron-based deoxidizer according to claim 1 in deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The raw materials for preparation are 65-75 wt.% iron powder, 10-25 wt.% anhydrous sodium sulfate, 1.0-5.0 wt.% sodium bromide, 0.5-1.5 wt.% activated carbon, and 3.0-5.0 wt.% glycerol aqueous solution.

3. The application of the iron-based deoxidizer according to claim 1 in the deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The concentration of the glycerol aqueous solution is 0.5~4.5 wt.%.

4. The application of the iron-based deoxidizer according to claim 1 in deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The iron-based deoxidizer has a mass of 1.5~2.5g.

5. The application of the iron-based deoxidizer according to any one of claims 1 to 4 in the deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The preparation method of the iron-based deoxidizer includes the following steps: (1) Add glycerol to water to prepare the glycerol aqueous solution; (2) Mix the iron powder and the activated carbon and stir, then add the glycerol aqueous solution while stirring and mix. (3) Add the anhydrous sodium sulfate and the sodium bromide, mix and seal.

6. The application of the iron-based deoxidizer according to claim 5 in deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The encapsulation is performed in a breathable packaging film.

7. The application of the iron-based deoxidizer according to claim 6 in deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The breathable packaging film is sealed on three sides.

8. The application of the iron-based deoxidizer according to claim 1 in deoxidation, dehumidification, and drying of food or pharmaceuticals, characterized in that, The iron-based deoxidizer is sealed together with the medicine in the packaging.

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