JP2021183309A - Deoxidant, production method of the same, deoxidant package and food product package - Google Patents

Abstract

To provide a granular deoxidant where oxygen absorption capacity is further improved.SOLUTION: A deoxidant is powders containing a plurality of composite particles having a granulated material including a porous carrier and an oxygen absorbing composition carried by the carrier and inorganic fine particles stuck on the surface of the granulated material. The oxygen absorbing composition contains glycerol, copper sulfate and an alkaline compound. The sedimentation rate of the composite particles in an aqueous solution containing glycerol and copper sulfate is 2 mm/s or more per one particle.SELECTED DRAWING: None

Description

The present invention relates to an oxygen scavenger and a method for producing the same. The present invention also relates to an oxygen scavenger package containing an oxygen scavenger and a food package.

Oxygen scavengers may be encapsulated in food packaging for long-term storage of food. Conventional general oxygen scavengers are granules in which a liquid oxygen absorbent substance is granulated together with a carrier (for example, Patent Documents 1 to 3).

Japanese Patent No. 4821692 Japanese Unexamined Patent Publication No. 2003-144112 Japanese Patent No. 3541859

A main object of the present invention is to further improve the oxygen absorption capacity of a granular oxygen scavenger.

One aspect of the present invention comprises a plurality of granulations, including a porous carrier and an oxygen absorbing composition carried on the carrier, and inorganic fine particles adhering to the surface of the granulation. An oxygen scavenger that is a powder containing composite particles, wherein the oxygen absorbing composition contains glycerin, copper sulfate, and an alkaline compound, and the precipitation rate of the composite particles in an aqueous solution containing glycerin and copper sulfate is one. It is an oxygen scavenger that is 2 mm / sec or more per second.

Another aspect of the present invention is in an aqueous solution containing glycerin and copper sulfate in which inorganic fine particles are attached to a granulated product containing a porous carrier and an oxygen absorbing composition supported on the carrier. This is a method for producing an oxygen scavenger, which comprises a step of adhering inorganic fine particles forming composite particles so that the sedimentation rate in each particle is 2 mm / sec or more.

Granulation is performed so that the oxygen absorption composition contains glycerin, copper sulfate, and an alkaline compound, and the sedimentation rate of the composite particles in an aqueous solution containing glycerin and copper sulfate is 2 mm / sec or more per particle. By adhering the inorganic fine particles to the surface of an object, the oxygen absorption inherent in glycerin is exhibited, and an oxygen scavenger having an improved oxygen absorption capacity can be obtained.

The present invention also provides an oxygen scavenger package comprising the oxygen scavenger and a breathable packaging material containing the oxygen scavenger. The present invention further provides a food package including the oxygen scavenger package and a food package container in which the oxygen scavenger package is enclosed.

The present invention can provide a granular oxygen scavenger with improved oxygen absorption capacity.

Hereinafter, some embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

The oxygen scavenger according to one embodiment is mainly composed of a granulated product containing a porous carrier and an oxygen absorbing composition supported on the carrier, and inorganic fine particles adhering to the surface of the granulated product. It is a composite particle composed.

The carrier may be any porous particles capable of supporting the oxygen absorbing composition. Usually, the carrier is supported by impregnating the carrier with an oxygen absorbing composition. The carrier is selected from, for example, activated carbon, zeolite particles, bentonite particles, activated alumina particles, activated clay, calcium silicate particles, and diatomaceous earth.

The oxygen absorption composition contains glycerin, copper sulfate, and an alkaline compound.

The amount of glycerin is usually 80 to 200 parts by mass and may be 100 to 180 parts by mass with respect to 100 parts by mass of the carrier. When the amount of glycerin is within these ranges, it tends to be easy to obtain an oxygen scavenger having an appropriate oxygen absorption capacity.

The presence of water may be preferred for the oxygen absorption reaction. Therefore, 30 to 85 parts by mass of water, particularly 30 to 70 parts by mass of water may be added to 100 parts by mass of glycerin. When the amount of water is within these ranges, it tends to be easy to obtain an oxygen scavenger having an appropriate oxygen absorption capacity.

An alkaline compound is a compound that forms an alkaline aqueous solution when dissolved in water. The oxygen absorption reaction is activated by ionizing the hydroxyl group of glycerin with an alkaline compound. In the state of the oxygen absorption composition, a part of the alkaline compound is often dissolved in glycerin. The alkaline compound may be an alkali metal or alkaline earth metal hydroxide, carbonate, bicarbonate, tertiary phosphate, or secondary phosphate. Alkaline compounds include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide, beryllium hydroxide, magnesium hydroxide, calcium hydroxide, strontium hydroxide, radium hydroxide, lithium carbonate, sodium carbonate, Selected from the group consisting of calcium carbonate, magnesium carbonate, potassium carbonate, potassium hydrogencarbonate, sodium hydrogencarbonate, lithium hydrogencarbonate, sodium tertiary phosphate, potassium tertiary phosphate, sodium secondary phosphate, and potassium secondary phosphate. It may be one or more compounds.

The amount of the alkaline compound is usually 100 to 300 parts by mass and may be 150 to 250 parts by mass with respect to 100 parts by mass of the carrier. When the amount of the alkaline compound is within these ranges, it tends to be easy to obtain an oxygen scavenger having an appropriate oxygen absorption capacity.

Copper sulphate is added to accelerate the oxygen absorption reaction of glycerin. Copper sulfate is often dissolved in glycerin in the state of an oxygen absorbing composition. The copper sulfate may be a sulfate of copper, and may be anhydrous, pentahydrate, or other hydrate. Further, it may be copper sulfate (I) or copper sulfate (II) regardless of the oxidation number.

The amount of copper sulfate is 15 to 30 parts by mass and may be 18 to 26 parts by mass with respect to 100 parts by mass of glycerin in terms of anhydride. When the amount of the transition metal compound is within these ranges, it tends to be easy to obtain an oxygen scavenger having an appropriate oxygen absorbing capacity.

The carrier or oxygen absorbing composition may contain a binder so that the granulated product can be easily formed. Specific examples of the binder include gum arabic, polyvinyl alcohol, sodium alginate, gelatin and cellulose. The amount of the binder is usually 0 to 30 parts by mass and may be 10 to 20 parts by mass with respect to 100 parts by mass of the carrier.

The oxygen absorption composition may further contain other substances. Examples of other substances include catechol compounds. The amount of other substances is usually about 30 parts by mass or less with respect to 100 parts by mass of the carrier.

The particle size (maximum width) of the granulated product before the inorganic fine particles adhere is not particularly limited, but may be, for example, 0.3 mm or more, 8.0 mm or less, 4.5 mm or less, 1.8 mm or less, Alternatively, it may be 1.5 mm or less. The shape of the granulated product is not particularly limited, but may be columnar or spherical, for example. In the case of a columnar granulated product, the length of the side surface thereof may be 0.3 mm or more and may be 4.5 mm or less. The diameter of the bottom surface of the columnar column may be 0.3 mm or more, 1.8 mm or less, or 1.5 mm or less. Smaller particle sizes or sizes of granules tend to provide higher oxygen absorption capacity.

The granulated product composed of the carrier and the oxygen absorbing composition can be obtained by granulating a mixture containing the carrier and the components constituting the oxygen absorbing composition. The components constituting the oxygen absorption composition may be mixed together or separately. The mixer for mixing is not particularly limited, and may be, for example, a container rotary type mixer such as a cylindrical type or a V type, a ribbon type, a horizontal screw type, a paddle type, or a planetary motion type. It may be a container fixed type mixer such as.

The granulated product can be obtained by, for example, granulation by extrusion granulation, stirring granulation, fluidized bed granulation, rolling granulation, or compression granulation. Extrusion granulation can be performed, for example, using a screen having a predetermined opening. The granulated product obtained by extrusion granulation is often columnar.

Inorganic fine particles are water-insoluble particles containing an inorganic substance as a main component. The inorganic fine particles usually contain 50 parts by mass or more of inorganic substances based on the total mass thereof. The inorganic substance may be at least one selected from the group consisting of, for example, silicon dioxide, calcium silicate hydrate, and magnesium oxide. By adhering the inorganic fine particles to the surface of the granulated product, the surface area of the granulated product can be expanded and the oxygen absorption performance can be improved.

The higher the rate at which the oxygen absorbing composition of the inorganic fine particles attached to the granulated product is absorbed, the faster the oxygen absorbing composition contained inside the granulated product can be transferred to the inorganic fine particles, and the more oxygen there is. Absorption performance can be improved. The rate at which the oxygen absorbing composition is absorbed is determined by the affinity between the inorganic fine particles and the aqueous solution containing glycerin and copper sulfate.

The affinity between the inorganic fine particles and the aqueous solution can be grasped as the sedimentation rate of the composite particles in the aqueous solution. The granulated product to which the inorganic fine particles do not adhere has a lower density than the aqueous solution, and the affinity between the surface of the granulated product and the aqueous solution is low, so that the granulated product does not settle. On the other hand, in the composite particles in which the inorganic fine particles having a high affinity with the aqueous solution are attached to the surface of the granulated product, the inorganic fine particles on the surface absorb the aqueous solution and the composite particles become heavy and settle. The higher the affinity between the inorganic fine particles and the aqueous solution, the faster the absorption rate of the aqueous solution and the faster the sedimentation rate. By evaluating this affinity using the sedimentation rate, the oxygen absorption rate can be evaluated.

The concentration of the aqueous solution is 15 to 30 parts by mass in terms of anhydrate with respect to 100 parts by mass of glycerin, and the amount of copper sulfate may be 18 to 26 parts by mass. Further, the amount of water is 30 to 85 parts by mass and may be 30 to 70 parts by mass with respect to 100 parts by mass of glycerin. It is preferable that the concentration of the aqueous solution is the same as the concentration of the oxygen absorbing composition contained in the granulated product. When the concentration of the aqueous solution and the oxygen absorbing composition are the same, the ease of transfer of the oxygen absorbing composition to the inorganic fine particle portion can be quantified more accurately.

When the sedimentation rate of the composite particles is 2 mm / sec or more per composite particle, a high oxygen absorption capacity tends to be obtained. From the same viewpoint, the sedimentation rate per composite particle may be 2.5 mm / sec or more, 5 mm / sec or more, or 10 mm / sec or more. The upper limit of the settling speed is not particularly limited. Further, the mass of the composite particles can be, for example, 0.3 to 10.0 mg per particle.

The settling rate of the composite particles is the time required for the settling composite particles to reach the bottom surface of the container by placing an aqueous solution containing glycerin and copper sulfate in a container of a certain volume and gently placing one composite particle on the liquid surface. , Can be determined by the distance from the bottom of the container to the liquid level. Details of the method for measuring the sedimentation rate will be described in Examples described later.

The average particle size of the inorganic fine particles may be 150 μm or less. When the average particle size of the inorganic fine particles is 150 μm or less, the oxygen absorption capacity of the oxygen scavenger can be further improved. Fine irregularities are usually formed on the surface of the granulated product, and inorganic fine particles having a small particle size easily enter the recesses on the surface of the granulated product. As a result, the surface area of the granulated product is significantly increased, which is considered to contribute to the improvement of the oxygen absorption capacity. From the same viewpoint, the average particle size of the inorganic fine particles may be 100 μm or less, or 50 μm or less. The lower limit of the average particle size is not particularly limited, but may be, for example, 0.1 μm or more because nano-sized fine particles are expensive and difficult to handle. The average particle size here is a value of the secondary particle size measured by the laser diffraction method.

The pore volume of the inorganic fine particles may be 0.5 mL / g or more. When the pore volume of the hydrophilic inorganic fine particles is 0.5 mL / g or more, the oxygen absorption capacity of the oxygen scavenger can be further improved. It is considered that the inorganic fine particles having a large pore volume easily absorb the oxygen absorbing composition near the surface of many granulated products. When the oxygen absorbing composition is absorbed by the inorganic fine particles, it is presumed that the area of contact between the oxygen absorbing composition and oxygen in the environment increases, and as a result, the oxygen absorbing capacity is improved. From the same viewpoint, the pore volume of the inorganic fine particles may be 0.8 mL / g or more, or 1.2 mL / g or more. The upper limit of the pore volume is not particularly limited, but may be, for example, 10 mL / g or less. The pore volume here is a value measured by a nitrogen adsorption method or a mercury intrusion method. The pore volume measured by at least one of the nitrogen adsorption method and the mercury intrusion method may be within the above numerical range.

Inorganic fine particles having the above-exemplified average particle size and pore volume can be produced by a usual method, and can also be appropriately selected and obtained from commercially available products.

The amount (adhesion amount) of the inorganic fine particles adhering to the surface of the granulated product is 0.1 part by mass or more, 0.5 part by mass or more, and 1 part by mass or more with respect to 100 parts by mass of the granulated product. It may be 2 parts by mass or more or 3 parts by mass or more. When the amount of adhered inorganic fine particles is within these ranges, it is easy to obtain an appropriate oxygen absorption capacity of the oxygen scavenger. The upper limit of the adhesion amount of the inorganic fine particles is not particularly limited, but may be 30 parts by mass or less, 25 parts by mass or less, 15 parts by mass or less, 10 parts by mass or less, or 8 parts by mass or less from the viewpoint of granulation property. good. The single inorganic fine particles that are not attached to the granulated product may be mixed with the particles of the oxygen scavenger, but the amount of the single inorganic fine particles is not included in the above-mentioned adhered amount.

The volume ratio of the granulated product based on the entire oxygen scavenger may exceed 60%. When the volume ratio of the granulated product is in an appropriate range, it is easy to obtain a particularly high oxygen absorption capacity. From the same viewpoint, the volume ratio of the granulated product may be 70% or more, 80% or more, or 98% or less.

Inorganic microparticles are usually attached over the entire surface of the granulated material. However, the surface of the granulated product does not necessarily have to be covered with the inorganic fine particles without gaps, and the inorganic fine particles may be distributed over the entire surface of the granulated product while being spaced apart from each other.

The oxygen scavenger can be obtained by a method comprising a step of adhering inorganic fine particles to a granulated product containing a carrier and an oxygen absorbing composition. For example, by mixing the granulated product and the inorganic fine particles and shaking the obtained powder mixture, the inorganic fine particles can be attached to the granulated product.

The inorganic fine particles adhering to the granulated product by the method of mixing the powders as described above form a relatively thin layer, and in this respect, the form of the oxygen scavenger of the present embodiment is, for example, tableting. It is generally different from tablets having an outer shell obtained by molding. Specifically, the inorganic fine particles adhering to the surface of the granulated product can form a layer having a thickness of 1 mm or less or 0.7 mm or less. The thin layer of inorganic fine particles is contained in the material (glycerin, alkaline compound or copper sulfate) constituting the granule when the surface of the composite particle is elementally analyzed by energy dispersive X-ray analysis (EDX analysis). Since the element is detected, it can be confirmed. Generally, in the case of the oxygen scavenger according to the present embodiment, at least one element contained in the material constituting the granulated product is detected at a concentration of 0.05 atomic number% or more or 0.1 atomic number% or more. Often done. On the other hand, when the outer portion having a certain thickness containing the granulated product is formed by tableting, the elements of the material constituting the granulated product are not substantially detected by the EDX analysis.

The oxygen scavenger package according to one embodiment may be mainly composed of the oxygen scavenger according to the above embodiment and a breathable packaging material containing the oxygen scavenger. The breathable packaging material can be appropriately selected from those commonly used in the art. Specific examples of the breathable packaging material include a bag formed of a perforated plastic film, a non-woven fabric, a microporous film, paper, or a base material made of a combination thereof. This oxygen scavenger package can be stored in various food packaging containers, for example, and used for the purpose of maintaining the freshness of food.

The food package according to the embodiment includes the above-mentioned oxygen scavenger package and a food package container in which the oxygen scavenger package is enclosed. The food packaging container can be appropriately selected from those usually used in the field of food packaging, and a sealable container is preferable. Examples of the food packaging container include a bag body, a deeply squeezed package body, a tray package body, a stretch package body and the like.

Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

1. 1. Granulations The raw materials shown in Table 1 are uniformly mixed in a sealed state to prepare a mixture containing activated carbon and an oxygen absorbing composition containing an oxygen scavenger, an alkaline compound, a transition metal salt and a binder supported on the activated carbon. Obtained. The obtained mixture was granulated by an extrusion granulator provided with a screen having a screen pore diameter of 1.0 mmφ and a pore opening rate of 22.6% to obtain granulated powder composed of granular granules. Table 1 shows the blending amount of each raw material by mass.

2. 2. Inorganic fine particles The following inorganic fine particles were prepared.
・ Silo page 720 (hydrophilic silicon dioxide powder, manufactured by Fuji Silysia Chemical Ltd.)
・ Nip seal SS-50B (hydrophobic silicon dioxide powder, manufactured by Tosoh Silica)
・ Calcium hydroxide (manufactured by Kanto Chemical Co., Inc.)

3. 3. Oxygen scavenger (Example 1)
30 g of granulated product and 1.5 g of silopage 720, which is a hydrophilic silicon dioxide powder, were placed in an oxygen barrier bag, and the bag was heat-sealed and sealed. The bag was shaken to form an oxygen scavenger whose granules were coated with inorganic fine particles. The bag was opened, heat-sealed again to expel the air inside, and the oxygen scavenger was stored.
(Example 2)
An oxygen scavenger was formed and stored in the same manner as in Example 1 except that 30 g of granulated product and 2.4 g of silopage 720 were placed in an oxygen barrier bag.
(Comparative Example 1)
An oxygen scavenger was formed and stored in the same manner as in Example 1 except that 30 g of granulated product and 6 g of calcium hydroxide were put in an oxygen barrier bag.
(Comparative Example 2)
An oxygen scavenger was formed and stored in the same manner as in Example 1 except that 30 g of granulated product and 1.5 g of calcium hydroxide were placed in an oxygen barrier bag.
(Comparative Example 3)
An oxygen scavenger was formed and stored in the same manner as in Example 1 except that 30 g of granulated product and 1.5 g of hydrophobic silicon dioxide were placed in an oxygen barrier bag.
(Comparative Example 4)
30 g of granulated material was placed in an oxygen barrier bag, and the bag was heat-sealed and stored without containing inorganic fine particles.

4. Settling speed The settling speed of the granulated product (composite particles) to which the inorganic fine particles were attached was measured by the following procedure.
(1) An aqueous solution of 30 parts by mass of copper (II) sulfate pentahydrate and 40 parts by mass of water was prepared with respect to 100 parts by mass of glycerin, and used as a solution A. This solution A was kept warm at 25 ° C.
(2) The oxygen scavenger was passed through a sieve having an opening of 1 mm, and composite particles requiring a particle size of 1 mm or more remaining on the sieve were selected.
(3) Solution A was poured into a cylindrical glass bottle having an opening with a diameter of 30 mm up to a distance of 50 mm from the bottom surface.
(4) One composite particle obtained in (2) was picked up with tweezers and gently placed on the liquid surface of the solution A of (3), and the time until the composite particle settled and reached the bottom surface of the glass bottle was measured. ..
(5) The sedimentation speed was calculated by the following formula. The average value of the values measured using five different composite particles was adopted.
Settlement speed [mm / s] = 50 [mm] / arrival time to the bottom [s]

5. Oxygen absorption capacity 2.0 g of oxygen scavenger was stored in a bag (length 60 mm, width 60 mm) formed of a perforated packaging material to prepare an oxygen scavenger package. As an effective packaging material, a laminated material composed of polyethylene terephthalate / polyethylene / paper / polyethylene was used. The oxygen scavenger package was placed in a gas barrier bag together with absorbent cotton (water activity 0.95) soaked with a 44% aqueous solution of sucrose. The bag was sealed, 500 mL of air was injected into it, and then the bag was left in an atmosphere of 25 ° C. The oxygen concentration in the bag after 24 hours was measured. When the oxygen concentration was 8% or less, it was judged as "○", when it was 13% or less, it was judged as "Δ", and when it was larger than 13%, it was judged as "×". A low oxygen concentration means a high oxygen absorption capacity.

6. Results Table 2 shows the types of inorganic fine particles, the sedimentation rate (average value of n = 5) of the composite particles to which the inorganic fine particles are attached, and the evaluation results of the oxygen absorption capacity. The reference example is an example in which the granulated product is not covered with inorganic fine particles and is used as it is as an oxygen scavenger. It was confirmed that an oxygen scavenger having a sedimentation rate of 2 mm / sec or more showed excellent oxygen absorption capacity.

The present invention is useful as an oxygen scavenger used for food preservation and the like.

Claims (10)

A powder containing a plurality of composite particles comprising a porous carrier and an oxygen absorbing composition carried on the carrier, the granulated product, and inorganic fine particles adhering to the surface of the granulated product. Oxygen scavenger, wherein the oxygen absorbing composition contains glycerin, copper sulfate, and an alkaline compound, and the precipitation rate of the composite particles in an aqueous solution containing glycerin and copper sulfate is 2 mm / sec per particle. The oxygen scavenger that is above. The concentration of the aqueous solution is 15 to 30 parts by mass of copper sulfate with respect to 100 parts by mass of glycerin, and the amount of water is 30 to 85 parts by mass with respect to 100 parts by mass of glycerin. The deoxidizer according to claim 1, which is a mass portion. The oxygen scavenger according to claim 1 or 2, wherein the amount of the inorganic fine particles is 2 to 30 parts by mass with respect to 100 parts by mass of the granulated product. The oxygen scavenger according to any one of claims 1 to 3, wherein the mass of the composite particles is 0.3 to 10.0 mg per particle. The oxygen scavenger according to any one of claims 1 to 4, wherein the inorganic fine particles adhering to the surface of the granulated product form a layer having a thickness of 1 mm or less. The inorganic fine particles adhere to the surface of the granulated product so that elements contained in glycerin, the alkaline compound or copper sulfate are detected when the surface of the composite particles is elementally analyzed by energy dispersive X-ray analysis. The deoxidizing agent according to any one of claims 1 to 5. The method for producing an oxygen scavenger according to any one of claims 1 to 6.
A production method comprising a step of adhering the inorganic fine particles to the granulated product to form the composite particles so that the sedimentation rate in an aqueous solution containing glycerin and copper sulfate is 2 mm / sec or more per particle. The production method according to claim 7, wherein the inorganic fine particles are adhered to the granulated product by mixing the granulated powder composed of the plurality of the granulated products and the plurality of the inorganic fine particles. An oxygen scavenger package comprising the oxygen scavenger according to any one of claims 1 to 6 and a breathable packaging material containing the oxygen scavenger. A food package comprising the oxygen scavenger package according to claim 9 and a food package container in which the oxygen scavenger package is enclosed.