Preservative for preventing and preserving bamboo shoots and preparation method thereof
Through the modified preservative that combines konjac glucomanan with deodorized garlic extract, the problem of poor preservation effect of bamboo shoots in the prior art is solved, effective anti-corrosion and freshness of bamboo shoots is achieved, extended the shelf life of bamboo shoots and maintained quality.
Patent Information
- Application Number
- CN202510002124.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2025-04-11
AI Technical Summary
The existing bamboo shoot preservation technology is difficult to maintain the quality and taste of bamboo shoots for a long time, and the coating of a single coating material cannot effectively inhibit the tidy and rottenness of bamboo shoots.
By oxidizing konjac glucomanan and ε-polylysine grafting reaction, modified konjac glucomanan was prepared and combined with deodorized garlic extract to prepare a fresh preservative for forming a uniform and dense coating on the surface of bamboo shoots.
This preservative can effectively reduce the evaporation of moisture on the surface of bamboo shoots, delay the rate of changes in bamboo shoot hardness, cellulose and lignin, inhibit the key enzyme activity of lignin synthesis, reduce the degree of lignification of bamboo shoots, and improve the preservation quality of bamboo shoots.
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Abstract
Description
Technical Field
[0001] The invention relates to the technical field of food preservation, and in particular to a preservative for preserving bamboo shoots and a preparation method thereof. Background Art
[0002] Bamboo shoots are the young shoots of bamboo or the swollen shoots of bamboo whips, also known as bamboo shoots or whip shoots. Bamboo shoots are rich in protein, dietary fiber, minerals, vitamins and a variety of bioactive ingredients, and are low in fat. They are forest vegetables with great nutritional and health value. However, bamboo shoots are very prone to dehydration, aging, browning, and a decrease in nutritional content after being harvested, which causes the quality of bamboo shoots to deteriorate rapidly and makes storage and transportation difficult. They easily lose their edible value in one to three days at room temperature. Therefore, bamboo shoot preservation and processing technology is a difficult problem that the bamboo shoot industry urgently needs to solve.
[0003] Preservation with preservatives is the most commonly used preservation technology in food. The use of preservatives to preserve and process bamboo shoots can delay the lignification and browning efficiency of bamboo shoots after harvesting, effectively prevent physiological diseases of bamboo shoots during storage, reduce physiological activity, inhibit microbial reproduction and delay tissue structure aging.
[0004] Existing bamboo shoot preservation technologies are mainly divided into physical preservation technology and chemical preservation technology. Physical preservation technology includes low-temperature refrigeration, modified atmosphere packaging, vacuum packaging and irradiation treatment, while chemical preservation technology mainly relies on artificial synthetic chemical preservatives such as preservatives, enzyme inhibitors, fumigants and coating preservatives to maintain the fresh quality of fruits and vegetables, reduce circulation losses and extend storage time. Among them, the coating preservative technology in chemical preservation technology mainly forms a layer of preservative coating with protective function on the surface of bamboo shoots by dipping, spraying and other methods. The coating materials mostly select polysaccharides, proteins, lipids and the like as the main raw materials. The preservative coating can isolate the direct contact between bamboo shoots and air to a certain extent, thereby inhibiting its respiration, reducing the consumption of its own nutrients, and is conducive to maintaining the quality of bamboo shoots within a certain time range. However, the coating of a single coating material cannot achieve a good preservation effect, and it is difficult to maintain the quality and taste of bamboo shoots for a long time. Summary of the invention
[0005] In view of the shortcomings and deficiencies of the prior art, the present invention provides a preservative for preserving and preserving bamboo shoots, which is helpful to form a uniform and dense coating on the surface of bamboo shoots, reduce water evaporation on the surface of bamboo shoots, maintain the moisture of bamboo shoots, delay the rate of change of bamboo shoot hardness, cellulose and lignin, reduce the consumption of total sugar, inhibit the activity of key enzymes for lignin synthesis, effectively reduce the degree of lignification of post-harvest bamboo shoots, effectively inhibit the corruption and deterioration of bamboo shoots, and improve the preservation quality of bamboo shoots, and a preparation method thereof.
[0006] A method for preparing a preservative for preserving bamboo shoots comprises the following steps:
[0007] S1: preparation of modified konjac glucomannan, after oxidizing konjac glucomannan, grafting ε-polylysine with the oxidized konjac glucomannan to obtain modified konjac glucomannan;
[0008] S2: Extraction and preparation of deodorized garlic extract, washing and peeling garlic, mashing it into garlic paste, and preparing garlic paste liquid with distilled water, and the garlic paste liquid is subjected to centrifugal separation and microwave treatment to obtain deodorized garlic extract;
[0009] S3: Preparation of a preservative: adding modified konjac glucomannan and deodorized garlic extract to distilled water in sequence, and shaking and mixing the mixture to obtain a preservative.
[0010] As a further technical solution, step S1: preparation of modified konjac glucomannan specifically comprises the following steps:
[0011] S1.1: 3-8 g of konjac glucomannan is dissolved in 200-250 mL of distilled water, and then 0.2-0.5 g of sodium periodate is added, and the mixture is stirred and reacted at room temperature in the dark for 18-24 h, and then 0.1-0.6 g of ethylene glycol is added to terminate the reaction to obtain a reaction solution;
[0012] S1.2: dialyzing the reaction solution in distilled water for 4 to 7 days using a dialysis bag, and freeze-drying the dialyzed substance to obtain oxidized konjac glucomannan;
[0013] S1.3: Take 1-5 g of ε-polylysine and add it to 50-120 mL of distilled water, stir and dissolve it, then add 3-5 g of oxidized konjac glucomannan, stir and react at 25-32° C. for 20-24 hours to obtain a mixture, dialyze the mixture in distilled water for 2-3 days using a dialysis bag, and freeze-dry to obtain modified konjac glucomannan.
[0014] As a further technical solution, the molecular weight cut-off of the dialysis bag is 3000Da.
[0015] As a further technical solution, step S2: extracting and preparing the deodorized garlic extract, specifically comprises the following steps:
[0016] The washed and peeled garlic is crushed into garlic paste, and the garlic paste is prepared into garlic paste liquid with a mass fraction of 30-50% with distilled water. The garlic paste liquid is centrifuged at 5000-8000 r / min for 10-15 minutes, and the supernatant is taken and subjected to microwave treatment to obtain a deodorized garlic extract.
[0017] As a further technical solution, the power of microwave treatment is 500-700W, the treatment time is 2-5min, and the treatment temperature is 36-50°C.
[0018] As a further technical solution, step S3: preparation of a preservative, specifically comprises the following steps:
[0019] 3-7.5 g of modified konjac glucomannan and 5-10 mL of deodorized garlic extract are sequentially added into 450-500 mL of distilled water, and the mixture is fully shaken and mixed to obtain a preservative.
[0020] A preservative for preserving and keeping bamboo shoots fresh is prepared by the preparation method of the preservative for preserving and keeping bamboo shoots fresh.
[0021] Compared with the prior art, the present invention has at least the following advantages:
[0022] 1. In the present invention, konjac glucomannan is oxidized to oxidize the hydroxyl groups on the konjac glucomannan into aldehyde groups, and then the oxidized konjac glucomannan is subjected to a grafting reaction with epsilon-polylysine, so that the epsilon-polylysine is evenly grafted and distributed in the molecular chain of konjac glucomannan. The obtained modified konjac glucomannan can exert the synergistic effect of epsilon-polylysine and konjac glucomannan, help to form a uniform and dense coating on the surface of bamboo shoots, reduce water evaporation on the surface of bamboo shoots, maintain the moisture of bamboo shoots, delay the rate of change of bamboo shoot hardness, cellulose and lignin, reduce the consumption of total sugar, inhibit the activity of key enzymes for lignin synthesis, effectively reduce the degree of lignification of post-harvest bamboo shoots, and improve the fresh-keeping quality of bamboo shoots.
[0023] 2. In the present invention, modified konjac glucomannan and deodorized garlic extract are used to prepare a preservative, and the preservative is used for the preservation of bamboo shoots. The various sulfides in the deodorized garlic extract have a broad-spectrum antibacterial effect on microorganisms, which can effectively prevent the bamboo shoots from being invaded by microorganisms and effectively inhibit the corruption and deterioration of the bamboo shoots. DETAILED DESCRIPTION
[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0025] Example 1
[0026] A method for preparing a preservative for preserving bamboo shoots, comprising the following steps:
[0027] S1: Preparation of modified konjac glucomannan,
[0028] S1.1: 8 g of konjac glucomannan was dissolved in 250 mL of distilled water, and then 0.5 g of sodium periodate was added. The mixture was stirred and reacted at room temperature in the dark for 24 h. Subsequently, 0.5 g of ethylene glycol was added to terminate the reaction to obtain a reaction solution.
[0029] S1.2: The reaction solution was dialyzed in distilled water for 7 days using a dialysis bag with a molecular weight cutoff of 3000 Da. The dialyzed substance was freeze-dried to obtain oxidized konjac glucomannan;
[0030] S1.3: 5 g of ε-polylysine was added to 120 mL of distilled water and stirred to dissolve, and then 5 g of oxidized konjac glucomannan was added, and the mixture was stirred and reacted at 32° C. for 24 h to obtain a mixture, and the mixture was dialyzed in distilled water for 3 days using a dialysis bag with a molecular weight cutoff of 3000 Da, and freeze-dried to obtain modified konjac glucomannan;
[0031] S2: Extraction and preparation of deodorized garlic extract,
[0032] The washed and peeled garlic was crushed into garlic paste, and the garlic paste was prepared into a garlic paste liquid with a mass fraction of 50% by distilled water. The garlic paste liquid was centrifuged at 8000r / min for 15min, and the supernatant was taken. The supernatant was subjected to microwave treatment at a power of 500w, a treatment time of 3min, and a treatment temperature of 42°C to obtain a deodorized garlic extract;
[0033] S3: Preparation of a preservative: 7.5 g of modified konjac glucomannan and 10 mL of deodorized garlic extract were added to 500 mL of distilled water in sequence, and the mixture was thoroughly shaken and mixed to obtain a preservative.
[0034] Example 2
[0035] A method for preparing a preservative for preserving bamboo shoots, comprising the following steps:
[0036] S1: Preparation of modified konjac glucomannan,
[0037] S1.1: 8 g of konjac glucomannan was dissolved in 250 mL of distilled water, and then 0.5 g of sodium periodate was added. The mixture was stirred and reacted for 18 h at room temperature in the dark. Subsequently, 0.5 g of ethylene glycol was added to terminate the reaction to obtain a reaction solution;
[0038] S1.2: The reaction solution was dialyzed in distilled water for 5 days using a dialysis bag with a molecular weight cutoff of 3000 Da, and the dialyzed substance was freeze-dried to obtain oxidized konjac glucomannan;
[0039] S1.3: 5 g of ε-polylysine was added to 120 mL of distilled water and stirred to dissolve, and then 5 g of oxidized konjac glucomannan was added, and the mixture was stirred and reacted at 25° C. for 20 h to obtain a mixture, and the mixture was dialyzed in distilled water for 2 days using a dialysis bag with a molecular weight cutoff of 3000 Da, and freeze-dried to obtain modified konjac glucomannan;
[0040] S2: Extraction and preparation of deodorized garlic extract,
[0041] The washed and peeled garlic was crushed into garlic paste, and the garlic paste was prepared into a garlic paste liquid with a mass fraction of 50% by distilled water. After the garlic paste liquid was centrifuged at 5000r / min for 15min, the supernatant was taken, and the supernatant was subjected to microwave treatment at a power of 700w, a treatment time of 2min, and a treatment temperature of 42°C to obtain a deodorized garlic extract;
[0042] S3: Preparation of a preservative: 7.5 g of modified konjac glucomannan and 10 mL of deodorized garlic extract were added to 500 mL of distilled water in sequence, and the mixture was thoroughly shaken and mixed to obtain a preservative.
[0043] Example 3
[0044] A method for preparing a preservative for preserving bamboo shoots, comprising the following steps:
[0045] S1: Preparation of modified konjac glucomannan,
[0046] S1.1: 3 g of konjac glucomannan was dissolved in 200 mL of distilled water, and then 0.2 g of sodium periodate was added. The mixture was stirred and reacted at room temperature in the dark for 24 h. Subsequently, 0.3 g of ethylene glycol was added to terminate the reaction to obtain a reaction solution;
[0047] S1.2: The reaction solution was dialyzed in distilled water for 7 days using a dialysis bag with a molecular weight cutoff of 3000 Da. The dialyzed substance was freeze-dried to obtain oxidized konjac glucomannan;
[0048] S1.3: 2 g of ε-polylysine was added to 60 mL of distilled water and stirred to dissolve, and then 4 g of oxidized konjac glucomannan was added, and the mixture was stirred and reacted at 32° C. for 24 h to obtain a mixture, and the mixture was dialyzed in distilled water for 3 days using a dialysis bag with a molecular weight cutoff of 3000 Da, and freeze-dried to obtain modified konjac glucomannan;
[0049] S2: Extraction and preparation of deodorized garlic extract,
[0050] The washed and peeled garlic was crushed into garlic paste, and the garlic paste was prepared into a garlic paste liquid with a mass fraction of 30% with distilled water. The garlic paste liquid was centrifuged at 8000r / min for 15min, and the supernatant was taken. The supernatant was subjected to microwave treatment at a power of 500w, a treatment time of 3min, and a treatment temperature of 42°C to obtain a deodorized garlic extract;
[0051] S3: Preparation of a preservative: 5 g of modified konjac glucomannan and 5 mL of deodorized garlic extract were added to 450 mL of distilled water in sequence, and the mixture was thoroughly shaken and mixed to obtain a preservative.
[0052] Comparative Example 1
[0053] Compared with Example 1, the difference of Comparative Example 1 is that the modified konjac glucomannan in step S3 is replaced by konjac glucomannan, and the other steps remain unchanged to prepare a preservative, which is recorded as Comparative Example 1.
[0054] Comparative Example 2
[0055] Compared with Example 1, the difference of Comparative Example 2 is that the modified konjac glucomannan in step S3 is replaced by ε-polylysine, and the other steps remain unchanged to prepare a preservative, which is recorded as Comparative Example 2.
[0056] Comparative Example 3
[0057] Compared with Example 1, the difference of Comparative Example 3 is that the modified konjac glucomannan in step S3 is replaced by a mixed powder obtained by stirring and mixing ε-polylysine and konjac glucomannan in a mass ratio of 1:1 in an anhydrous state, and the other steps remain unchanged to prepare a preservative, which is recorded as Comparative Example 3.
[0058] Comparative Example 4
[0059] Compared with Example 1, the difference of Comparative Example 4 is that the step of adding the deodorized garlic extract in step S3 is removed, and the other steps remain unchanged to prepare the preservative, which is recorded as Comparative Example 4.
[0060] Test Case
[0061] After cleaning the surface of freshly excavated bamboo shoots, select bamboo shoots with uniform individuals, similar diameters and lengths, consistent growth time, and no mechanical damage and pests, and use the preservatives obtained in Examples 1-3 and Comparative Examples 1-4 to preserve the bamboo shoots: After soaking in the preservative for 5 minutes, the bamboo shoots are naturally dried in the dark. The bamboo shoots are grouped according to the preservatives soaked, and the treated bamboo shoots are bagged into food-grade PE fresh-keeping self-sealing bags. After the bags are packaged, they are labeled with dates and stored in a constant temperature and humidity chamber at a temperature of 4±0.5°C and a relative humidity of 90%. Observe and test on 0, 3, 6, 9, 12, 15, and 18 days, respectively. Each time the sample is sampled, the surface is rinsed with pure water and the surface moisture is wiped off with absorbent paper before the detection operation is performed.
[0062] The test results are shown in Table 1 below.
[0063] Table 1:
[0064]
[0065]
[0066] As shown in Table 1, after the bamboo shoots were treated with the preservatives of Examples 1-3, during the storage process within 30 days, the hardness of the bamboo shoots changed little, the water content and the total sugar content lost less, and the lignin and cellulose contents increased slowly. The results of various test indicators were better than those of the preservatives of Comparative Examples 1-4, indicating that the modified konjac glucomannan and the deodorized garlic extract in the preservatives can have a good preservative and fresh-keeping effect on the bamboo shoots, and the ε-polylysine and konjac glucomannan in the modified konjac glucomannan can effectively prevent and cure the bamboo shoots. The synergistic effects of mannans can significantly ensure the preservation quality of bamboo shoots and delay the change rate of bamboo shoot hardness, total sugar, cellulose and lignin during the preservation process. Among them, the modified konjac glucomannan has the most significant effect on reducing water evaporation on the surface of bamboo shoots, maintaining the moisture of bamboo shoots, delaying the change rate of bamboo shoot hardness, cellulose and lignin, and reducing total sugar consumption. This shows that modified konjac glucomannan can exert the synergistic effect of ε-polylysine and konjac glucomannan, optimize the preservation quality of bamboo shoots, and improve the quality of bamboo shoots.
[0067] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to allow people familiar with the technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. For ordinary technicians in the field, they can make improvements or changes based on the above description, and all these improvements and changes should belong to the protection scope of the claims attached to the present invention. Parts not described in detail in this specification belong to the prior art known to professional and technical personnel in the field.
Claims
1. A method for preparing a preservative for preserving bamboo shoots, characterized in that: The steps include: S1: preparation of modified konjac glucomannan, after oxidizing konjac glucomannan, grafting ε-polylysine with the oxidized konjac glucomannan to obtain modified konjac glucomannan; S2: Extraction and preparation of deodorized garlic extract, washing and peeling garlic, mashing it into garlic paste, and preparing garlic paste liquid with distilled water, and the garlic paste liquid is centrifuged and microwave treated to obtain deodorized garlic extract; S3: Preparation of a preservative: adding modified konjac glucomannan and deodorized garlic extract to distilled water in sequence, and shaking and mixing the mixture to obtain a preservative.
2. The method for preparing a preservative for preserving bamboo shoots according to claim 1, characterized in that: step S1: Preparation of modified konjac glucomannan, specifically comprising the following steps: S1.1: 3-8 g of konjac glucomannan is dissolved in 200-250 mL of distilled water, and then 0.2-0.5 g of sodium periodate is added, and the mixture is stirred and reacted at room temperature in the dark for 18-24 h, and then 0.1-0.6 g of ethylene glycol is added to terminate the reaction to obtain a reaction solution; S1.2: dialyzing the reaction solution in distilled water for 4 to 7 days using a dialysis bag, and freeze-drying the dialyzed substance to obtain oxidized konjac glucomannan; S1.3: Take 1-5 g of ε-polylysine and add it to 50-120 mL of distilled water, stir and dissolve it, then add 3-5 g of oxidized konjac glucomannan, stir and react at 25-32° C. for 20-24 hours to obtain a mixture, dialyze the mixture in distilled water for 2-3 days using a dialysis bag, and freeze-dry to obtain modified konjac glucomannan.
3. The method for preparing a preservative for preserving bamboo shoots according to claim 2, characterized in that: The molecular weight cut-off of the dialysis bag is 3000Da.
4. The method for preparing a preservative for preserving bamboo shoots according to claim 1, characterized in that: Step S2: Extraction and preparation of deodorized garlic extract, specifically comprising the following steps: The washed and peeled garlic is crushed into garlic paste, and the garlic paste is prepared into garlic paste liquid with a mass fraction of 30-50% with distilled water. The garlic paste liquid is centrifuged at 5000-8000 r / min for 10-15 minutes, and the supernatant is taken and subjected to microwave treatment to obtain a deodorized garlic extract.
5. The method for preparing a preservative for preserving bamboo shoots according to claim 4, characterized in that: The power of the microwave treatment is 500-700W, the treatment time is 2-5min, and the treatment temperature is 36-50℃.
6. The method for preparing a preservative for preserving bamboo shoots according to claim 1, characterized in that: Step S3: Preparation of preservative, specifically comprising the following steps: 3-7.5 g of modified konjac glucomannan and 5-10 mL of deodorized garlic extract are sequentially added into 450-500 mL of distilled water, and the mixture is fully shaken and mixed to obtain a preservative.
7. A preservative for preserving bamboo shoots, characterized in that: The preservative is prepared by the method for preparing a preservative for preserving and preserving bamboo shoots according to any one of claims 1 to 6.