CN110150369B - Deoxidation and preservation method for pleurotus eryngii - Google Patents

Abstract

The invention relates to a method for deoxidizing fresh-keeping of Pleurotus eryngii, and belongs to the technical field of fresh-keeping of edible fungi. It includes the following steps (1) activation of iron powder; (2) sustained release of activated iron powder: the activated iron powder is wrapped with hydrophobically modified sodium alginate; (3) configuration of deoxidizer: the deoxidizer is an iron-based deoxidizer; ( 4) Packaging of deoxidizer: put the prepared deoxidizer into a small air-permeable and perforated packaging bag with a length of 4cm and a width of 3cm; (5) Pre-cooling of raw materials: place the king oyster mushroom in an environment of 8 ℃ for pre-cooling for 24 hours ; (6) Packing of raw materials: Pack the pre-cooled loquats into transparent polyethylene packaging bags; (7) Deoxygenation packaging; (8) Low temperature storage. The fresh-keeping method of the invention can significantly prolong the refrigerating period of the king oyster mushroom, and better maintain the original flavor and taste of the king oyster mushroom. The method is easy to operate, safe, non-toxic and low in cost, and has broad market application prospects.

Description

A kind of deoxygenation preservation method of king oyster mushroom

technical field

The invention relates to a method for deoxidizing fresh-keeping of Pleurotus eryngii, and belongs to the technical field of fresh-keeping of edible fungi.

Background technique

Oxygen scavenger is a new technology currently being studied and used in the field of fresh food preservation. They can consume free oxygen or combined oxygen in the air through the reaction of chemical components. Sealing the deoxidizer with the food can prevent the oxidative discoloration of the food and inhibit the growth of aerobic and aerobic microorganisms. A commonly used deoxidizer is an iron-based deoxidizer, which has high efficiency and low cost, and its deoxidation reaction can be carried out quickly under the condition of water and oxygen. The deoxygenation packaging of fresh fruits and vegetables is rarely used, because the respiration in the packaging space can release a large amount of water, the deoxygenation reaction proceeds rapidly and the deoxidizer is consumed in large quantities, resulting in poor deoxygenation effect in the later storage period.

Pleurotus eryngii is a kind of fungus with both medicinal and edible purposes, and has the reputation of "prairie delicious porcini". Pleurotus eryngii is bright in color, white and spotless, and delicious in taste, and is deeply loved by consumers. Pleurotus eryngii is rich in nutrients, containing low-fat, high-protein and various amino acids necessary for the human body, as well as trace elements such as iron and zinc. Pleurotus eryngii is a kind of precious fungus, it still has a high metabolic activity after harvest, which can consume a lot of nutrients in the body, resulting in a decline in quality, which is manifested as weightlessness, opening of the umbrella, growth of the stipe, and the tissue is water-soaked. Browning occurs. The conventional fresh-keeping technology has not achieved the desired effect, so it is necessary to find a fresh-keeping technology suitable for the post-harvest storage of eryngium eryngii. At present, there is no report on the deoxygenation preservation technology of eryngium eryngii.

The patent (publication number CN105394167A, published on March 16, 2016) discloses "a preservative for Pleurotus eryngii and its preparation method", and the patent (publication number CN107258891A, published on October 20, 2017) discloses "a "Preservation and Processing Technology of Pleurotus eryngii" all pointed out the preservation method of Pleurotus eryngii. Generally, by preparing a preservative, the preservative is directly and evenly sprayed on the surface of the king oyster mushroom, but there is no mention of packaging the preservative directly and sealing it together with the king oyster mushroom.

The method for deoxygenation and fresh-keeping of Pleurotus eryngii described in the invention can effectively and lastingly reduce the ratio of O ₂ and CO ₂ in the airtight inner space, reduce the respiration and postharvest metabolic process of Pleurotus eryngii, and inhibit the postharvest disease of Pleurotus eryngii Occurrence and growth of microorganisms, while significantly prolonging the storage period of Pleurotus eryngii. The deoxygenation preservation cost is low, the process is simple and the preservation effect is good, which can ensure the storage quality of the king oyster mushroom in the process of storage and commercial circulation.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a method for deoxygenation and preservation of Pleurotus eryngii, which solves the problems of short postharvest storage period of Pleurotus eryngii and the possible adverse effects of preservative residue on human body. The method can effectively prolong the preservation period of Pleurotus eryngii without Poisonous, harmless, low cost and easy to operate, fully guaranteeing the refrigerated quality and nutritional value of the king oyster mushroom.

The object of the present invention is achieved in this way, a kind of deoxygenation preservation method of king oyster mushroom is characterized in that, the king oyster mushroom after pre-cooling is directly packed into a polyethylene packaging bag, and a slow-release type deoxidizer is added therein and then sealed, It is refrigerated in the cold storage to realize the deoxygenation and preservation of the king oyster mushroom.

The slow-release deoxidizer added in the polyethylene packaging bag is 1 package of the slow-release deoxidizer, and the preparation method of the slow-release deoxidizer comprises the following steps:

(1) Iron powder activation;

Mix 30g of reduced iron powder with 200mL of hydrochloric acid with a concentration of 5%, boil for 10min, filter with suction and wash with deionized water until neutral, after suction filtration, dry it in a vacuum drying box at 70°C and 110-130pa for 1h to obtain activation. iron powder;

(2) Slow release of activated iron powder;

Dissolve 1.5 g of sodium alginate, 1.0 g of hydroxymethyl cellulose (CMC), and 0.3 g of glycerol into 100 mL of pH 6.0 phosphate buffer solution, stir magnetically at a constant temperature of 70 °C until dissolved, and degas at 0.095 MPa with a vacuum pump , to prepare sodium alginate solution, add 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl) 1 g and N-hydroxysuccinimide (NHS) 0.3 g, stir at 70°C for 30min, add 0.3g of ethylenediamine (EDA), after stirring for 2h, add 30g of activated iron powder, stir for 30min, wet the iron powder after suction filtration, put it in a vacuum drying box at 40°C and 110-130pa Dry to obtain slow-release activated iron powder, and the surface of the iron powder is covered with a hydrophobic sodium alginate film;

(3) Preparation of deoxidizer;

Mix 1-1.5 g of activated iron powder, 1-2 g of slow-release activated iron powder, 0.3-0.6 g of NaCl, 0.15-0.5 g of activated carbon, and 0.35-1 g of diatomaceous earth to obtain a deoxidizer.

(4) Deoxidizer packaging;

Pack the prepared deoxidizer into a small air-permeable and perforated packaging bag with a length of 4cm and a width of 3cm. The packaging bag is made of PET/PE composite material, and the hole diameter is less than 0.5mm to ensure that the content does not leak. The hole density is about 8 pcs/cm2 to obtain a packaged slow-release deoxidizer.

The pre-cooling of the Pleurotus eryngii is to place the Pleurotus eryngii in an environment of 8° C. for 24 hours to obtain the Pleurotus eryngii after the pre-cooling.

The polyethylene packaging bag has a length of 15cm, a width of 10cm and a thickness of 12μm, and the _O2 permeability coefficient is 2.87×10-10mL·cm/(m2·s·Pa); the average weight of the king oyster mushrooms in each polyethylene packaging bag is 500g.

The polyethylene packaging bag is sealed by heat sealing.

The temperature in the cold room was 4°C and the humidity was 75%.

The method of the invention is advanced and scientific, and it is convenient to use. Through the present invention, the present invention is realized by the following technical solutions. A method for deoxygenation and preservation of Pleurotus eryngii specifically comprises the following steps:

Step (1), iron powder activation: 30g of reduced iron powder is mixed with 200mL of hydrochloric acid with a concentration of 5%, boiled for 10min, suction filtered and washed with deionized water to neutrality, after suction filtration, vacuum drying at 70°C and 110-130pa Dry in the box for 1 hour to obtain activated iron powder.

Step (2), sustained release of activated iron powder: 1.5 g of sodium alginate, 1.0 g of hydroxymethyl cellulose (CMC), and 0.3 g of glycerol, dissolved in 100 mL of pH 6.0 phosphate buffer, and magnetic stirring at a constant temperature of 70 °C To dissolve, use a vacuum pump to degas at 0.095MPa to obtain a sodium alginate solution. Add 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC·HCl) 1g and N-hydroxysuccinimide (NHS) 0.3g, stir at 70°C for 30min, Add 0.3g of ethylenediamine (EDA), after stirring for 2h, add 30g of activated iron powder, stir for 30min, wet the iron powder after suction filtration, and dry it in a vacuum drying box at 40°C and 110-130pa to obtain a slow-release activation Iron powder, the surface of which is covered with a hydrophobic sodium alginate film.

Step (3), preparation of deoxidizer: 1-1.5 g of activated iron powder, 1-2 g of slow-release activated iron powder, 0.3-0.6 g of NaCl, 0.15-0.5 g of activated carbon, and 0.35-1 g of diatomaceous earth. Mix evenly to obtain deoxidizer;

Step (4), packaging of the deoxidizer: put the prepared deoxidizer into a breathable and perforated small packaging bag with a length of 4 cm and a width of 3 cm, the packaging bag is made of PET/PE composite material, and the hole diameter is less than 0.5 mm to ensure the content The material does not leak out, and the pore density is about 8/cm2;

Step (5), pre-cooling of raw materials: place king oyster mushrooms in an environment of 8°C and pre-cool for 24h;

Step (6), sub-packaging of raw materials: the pre-cooled king oyster mushrooms are sub-packed into transparent polyethylene packaging bags, and each bag has an average weight of 500 g; wherein, the transparent polyethylene packaging bags are 15 cm long, 10 cm wide, and 12 μm thick , O ₂ permeability coefficient is 2.87×10-10mL·cm/(m2·s·Pa);

Step (7), deoxygenation packaging: add a package of deoxidizer packaged in step (2) to the transparent polyethylene packaging bag containing Pleurotus eryngii, then heat-sealed;

Step (8), low temperature storage: store the deoxygenated and packaged Pleurotus eryngii in a cold storage with a temperature of 4° C. and a humidity of 75%.

The invention relates to a method for deoxidizing fresh-keeping of Pleurotus eryngii, and belongs to the technical field of fresh-keeping of edible fungi. It includes the following steps (1) activation of iron powder, (2) slow release of activated iron powder, (3) configuration of deoxidizer, (4) packaging of deoxidizer, (5) pre-cooling of raw materials, (6) sub-packaging of raw materials, (7) Deoxidized packaging, (8) low temperature storage. The fresh-keeping method of the invention can significantly prolong the refrigerating period of the king oyster mushroom, and better maintain the original flavor and taste of the king oyster mushroom. The method is easy to operate, safe, non-toxic and low in cost, and has broad market application prospects.

The invention mainly utilizes the deoxidizer to prolong the storage period of the king oyster mushroom, and the deoxygenated and packaged king oyster mushroom maintains good post-harvest quality. Compared with the prior art, the present invention has the following advantages by adding a deoxidizer to the independent small packaging method:

The deoxygenation and fresh-keeping method of the Pleurotus eryngii described in the present invention effectively adjusts the ratio of O ₂ and CO ₂ in the airtight packaging space, can rapidly reduce the O ₂ content in the package, and can maintain the low oxygen state for a long time, which not only reduces the reduction of the oxygen content of the Pleurotus eryngii The respiration effect of Pleurotus eryngii was inhibited, and the postharvest disease occurrence and microbial growth of Pleurotus eryngii were inhibited, and the storage period of Pleurotus eryngii was significantly prolonged. The method is non-toxic, harmless, simple in operation and low in cost, and fully guarantees the storage quality and nutritional value of the king oyster mushroom. During the low-temperature storage, the present invention can rapidly and lastingly reduce the oxygen level by adding a deoxidizer to the packaging bag containing the Pleurotus eryngii for independent packaging. Compared with the traditional method of spraying the antistaling agent on the surface of the Pleurotus eryngii, it shows great advantages. the superiority.

Description of drawings

Figure 1 is the effect of refrigeration of king oyster mushrooms.

Detailed ways

The technical solutions in the examples of the present invention are described in detail below.

Example 1: The deoxidizer contains the following components: 1 g of activated iron powder, 1 g of slow-release iron powder, 0.4 g of NaCl, 0.9 g of activated carbon, and 0.9 g of diatomaceous earth. in the packaging bag. Pleurotus eryngii without obvious mechanical damage and pests and diseases were selected and placed in an environment of 8°C for precooling for 24h. The pre-cooled king oyster mushrooms are divided into polyethylene transparent plastic bags, each bag weighing 500g. Into the polyethylene transparent plastic bags containing king oyster mushrooms, add a pack of deoxidizers in individual small packages (average weight of each bag is 4.2g), then seal the bag, and the remaining void gas volume of the polyethylene plastic bag is about 800mL. The sealed-packed Pleurotus eryngii was stored in a refrigerator with a temperature of 4°C and a humidity of 75%.

Example 2: The deoxidizer contains the following components: 1.2 g of activated iron powder, 1.5 g of slow-release iron powder, 0.5 g of NaCl, 0.4 g of activated carbon, and 0.6 g of diatomaceous earth, and the configured deoxidizer is filled with a length of 4 cm and a width of 3 cm. in the small packaging bag. Pleurotus eryngii without obvious mechanical damage and pests and diseases were selected and placed in a cold storage at 8°C for 24 hours. The pre-cooled king oyster mushrooms are divided into polyethylene transparent plastic bags, each bag weighing 500g. Into the polyethylene transparent plastic bags containing king oyster mushrooms, add a pack of deoxidizers in individual small packages (average weight of each bag is 4.2g), then seal the bag, and the remaining void gas volume of the polyethylene plastic bag is about 800mL. The sealed-packed Pleurotus eryngii was stored in a refrigerator with a temperature of 4°C and a humidity of 75%.

Example 3: The deoxidizer contains the following components: 1.5 g of iron powder, 2 g of slow-release iron powder, 0.5 g of NaCl, 0.1 g of activated carbon, and 0.1 g of diatomaceous earth. The configured deoxidizer is packed into a small package with a length of 4cm and a width of 3cm in the bag. Pleurotus eryngii without obvious mechanical damage and pests and diseases were selected and placed in a cold storage at 8°C for 24 hours. The pre-cooled king oyster mushrooms are divided into polyethylene transparent plastic bags, each bag weighing 500g. Into the polyethylene transparent plastic bags containing king oyster mushrooms, add a pack of deoxidizers in individual small packages (average weight of each bag is 4.2g), then seal the bag, and the remaining void gas volume of the polyethylene plastic bag is about 800mL. The sealed-packed Pleurotus eryngii was stored in a refrigerator with a temperature of 4°C and a humidity of 75%.

Storage experiments were carried out on the three kinds of deoxygenated Pleurotus eryngii in Examples 1-3 and the control Pleurotus eryngii without any treatment. They were stored in the same environment for 35 days, and 20 experienced reviewers were selected for sensory evaluation. Table 1 lists the sensory evaluation results of the Pleurotus eryngii and the Pleurotus eryngii without any treatment of the present invention.

Table 1 Sensory evaluation criteria and results of Pleurotus eryngii

As can be seen from Table 1 and Figure 1, compared with the control group without any treatment, the three kinds of deoxygenated packaged Pleurotus eryngii of the present invention were subjected to sensory evaluation after being refrigerated for 35d. The color, smell, taste and texture are obviously improved, and the main performance is that the color and luster of the Pleurotus eryngii stored by the fresh-keeping technology of the present invention is normal, no browning phenomenon occurs, and it has good elasticity. Therefore, the deoxygenation and fresh-keeping technology of the present invention can be very good. Storage and transportation of Pleurotus eryngii.

The embodiments of the present invention have been described above in detail, but these are merely examples for ease of understanding, and should not be construed as limiting the scope of the present invention. Likewise, any person skilled in the art can make various possible equivalent changes or substitutions according to the technical solutions of the present invention and the description of the preferred embodiments thereof, but all these changes or substitutions should belong to the claims of the present invention scope of protection.

Claims (5)

1. A method for deoxidizing and refreshing pleurotus eryngii is characterized in that precooled pleurotus eryngii is directly filled into a polyethylene packaging bag, a slow-release deoxidizing agent is added into the polyethylene packaging bag, the polyethylene packaging bag is sealed, and the polyethylene packaging bag is refrigerated in a refrigeration house to realize the deoxidizing and refreshing of the pleurotus eryngii;

the preparation method of the slow-release deoxidizer comprises the following steps:

(1) activating iron powder;

mixing 30g of reduced iron powder with 200mL of hydrochloric acid with the concentration of 5%, boiling for 10min, carrying out suction filtration, washing with deionized water to be neutral, and drying in a vacuum drying oven at 70 ℃ and 110 Pa for 1h after suction filtration to obtain activated iron powder;

(2) the activated iron powder is slowly released;

dissolving 1.5g of sodium alginate, 1.0g of hydroxymethyl cellulose (CMC) and 0.3g of glycerol into 100mL of phosphate buffer solution with pH of 6.0, magnetically stirring at constant temperature of 70 ℃ until the sodium alginate, degassing at 0.095MPa by using a vacuum pump to prepare a sodium alginate solution, adding 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (EDC.HCl) 1g and N-hydroxysuccinimide (NHS)0.3g, stirring at 70 ℃ for 30min, adding 0.3g of Ethylenediamine (EDA), stirring for 2h, adding 30g of activated iron powder, stirring for 30min, carrying out suction filtration, moistening the iron powder, drying in a vacuum drying oven at 40 ℃ and 110-130pa to obtain the slow-release activated iron powder, wherein the surface of the iron powder is covered with a hydrophobic sodium alginate film;

(3) preparing a deoxidizing agent;

uniformly mixing 1-1.5 g of activated iron powder, 1-2g of slow-release activated iron powder, 0.3-0.6 g of NaCl0.15-0.5 g of activated carbon and 0.35-1 g of diatomite to obtain a deoxidizer;

(4) packaging a deoxidizer;

filling the prepared deoxidizer into a small breathable and perforated packaging bag with the length of 4cm and the width of 3cm, wherein the packaging bag is made of PET/PE composite material, the diameter of each hole is less than 0.5mm, the content is ensured not to leak, and the density of each hole is about 8 holes/cm²And obtaining the packaged slow-release deoxidizer.

2. The method for deoxidizing and refreshing pleurotus eryngii according to claim 1, wherein the pleurotus eryngii precooling is performed by placing the pleurotus eryngii in an environment with the temperature of 8 ℃ for 24 hours to obtain precooled pleurotus eryngii.

3. The method for deoxidizing and refreshing pleurotus eryngii according to claim 1, wherein the polyethylene packaging bag has a length of 15cm, a width of 10cm and a thickness of 12 μm, and is O₂A transmission coefficient of 2.87X 10⁻¹⁰mL·cm/(m²S · Pa); each bag of the polyethylene packaging bags is 500g of pleurotus eryngii.

4. The deoxygenation and preservation method of Pleurotus eryngii according to claim 1, wherein the polyethylene packaging bag is sealed by heat sealing.

5. The method for deoxidizing and refreshing pleurotus eryngii according to claim 1, wherein the temperature in the refrigerator is 4 ℃ and the humidity is 75%.

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