Application of combination of plasma activated water and L-cysteine in quality and freshness preservation of agaricus bisporus and method thereof

Abstract

The invention provides application of plasma activated water combined with L-cysteine in quality and freshness preservation of agaricus bisporus and a method of the application, and relates to the technical field of edible mushroom freshness preservation. The plasma activated water and the L-cysteine are cooperatively applied to quality and freshness preservation of the agaricus bisporus, high-activity antibacterial substances are generated through the plasma activated water, and the L-cysteine is combined, so that the hardness of the agaricus bisporus can be effectively improved, oxidation of soluble solids in edible mushrooms can be delayed, and the color, the taste and the flavor of the agaricus bisporus can be effectively maintained; the synergistic sterilization and comprehensive fresh-keeping effects are realized. The method is beneficial to shelf-life storage and long-distance transportation, does not influence the color, taste and flavor of commodities, meets the requirements of consumers on high-quality edible mushrooms, improves the market competitiveness of products, and has wide application prospects.

Description

Technical Field

[0001] The invention belongs to the technical field of edible fungus preservation, and particularly relates to an application of plasma activated water combined with L-cysteine ​​in the preservation of Agaricus bisporus and a method thereof. Background Art

[0002] Agaricus bisporus, a cultivated edible mushroom worldwide, is consumed in significant quantities. Rich in minerals, vitamins, essential amino acids, and several bioactive substances, Agaricus bisporus exhibits browning, cap opening, stipe elongation, and texture changes within 1–3 days of harvest, significantly reducing its quality and limiting its commercialization. To extend the shelf life of Agaricus bisporus, prevent nutrient loss, and enhance its biochemical activity during storage, numerous researchers worldwide have explored a variety of emerging preservation technologies, including low-temperature refrigeration, modified atmosphere packaging, dehydration, irradiation, various bio-coatings, and chemical treatments, from the perspectives of postharvest storage, transportation, and commercialization. While these methods have proven effective, they also present limitations, such as limited preservation effectiveness, compromised taste, and low safety.

[0003] Traditional methods, such as chemical preservatives, can inhibit bacteria in the short term but may leave harmful residues, posing a health risk to consumers. While low-temperature refrigeration can slow spoilage, it consumes a lot of energy and cannot prevent metabolic losses. Modified atmosphere packaging, on the other hand, requires stringent equipment, making it difficult to widely use. Compared to existing edible fungus preservation methods, plasma-activated water (PAW) offers unique advantages in improving the physical and chemical properties of edible fungi during storage. However, while activated water treatment improves the physical and chemical properties of Agaricus bisporus during storage compared to untreated materials, it rapidly oxidizes the surface of the mushrooms, causing browning within 1 hour of treatment. This browning is a side effect of activated water treatment and can affect their commercial value. Therefore, to enhance the commercial value and long-term economic benefits of Agaricus bisporus, particularly in the high-end edible fungus market, which demands both "natural, additive-free" and stable quality, a method that can maintain the physical and chemical properties of Agaricus bisporus during storage and improve its color is urgently needed. Summary of the Invention

[0004] In response to the above technical problems, the first objective of the present invention is to provide the use of plasma-activated water combined with L-cysteine ​​to preserve the quality and freshness of Agaricus bisporus. This invention combines plasma-activated water with the color-protecting L-cysteine ​​to form a "physical-chemical" dual sterilization system. This system overcomes the negative effect of excessive plasma-activated water, which can cause Agaricus bisporus to turn brown. It also addresses the issue of oxidative browning of Agaricus bisporus after treatment with activated water, thereby enhancing its commercial value.

[0005] The second object of the present application is to provide a method for treating Agaricus bisporus by plasma-activated water combined with L-cysteine.

[0006] The third object of the present application is to provide an application of the above method in improving the color and taste of Agaricus bisporus.

[0007] To achieve the above objects, the technical solutions of the present application are as follows.

[0008] The present application provides an application of plasma-activated water combined with L-cysteine in the shelf-life preservation of Agaricus bisporus, wherein the concentration of L-cysteine is 0.05%-0.35%.

[0009] As an embodiment, the Agaricus bisporus is white variety.

[0010] The present application also provides a method for treating Agaricus bisporus by plasma-activated water combined with L-cysteine, which comprises the following steps: soaking Agaricus bisporus in plasma-activated water, then soaking the treated Agaricus bisporus in 0.05%-0.35% L-cysteine solution, and refrigerating.

[0011] As an embodiment, the mass-volume ratio of Agaricus bisporus to plasma-activated water is 1:(1-5) g / mL, and the soaking time in the plasma-activated water is 10-20 min.

[0012] As an embodiment, the preparation method of the plasma-activated water comprises the following steps: placing the nozzle of a low-temperature plasma jet device below the liquid surface of deionized water by 20-30 cm and discharging for 10-20 min.

[0013] As an embodiment, the power of the low-temperature plasma jet device is 700-800 VA, the working frequency is 20-30 kHz, and the discharge gas is air.

[0014] As an embodiment, the working air pressure of the air is 0.15-0.2 MPa, and the gas flow is 25-35 L / min.

[0015] As an embodiment, the soaking time in the L-cysteine solution is 8-10 min.

[0016] As an embodiment, the refrigeration is cold storage in a preservation box.

[0017] The present application also provides an application of the above method in improving the color and taste of Agaricus bisporus.

[0018] Compared with the prior art, the present application has the following beneficial effects:

[0019] The low-temperature plasma activated water of the present invention produces a variety of antibacterial active substances (such as active oxygen and active nitrogen), and its permeability and bactericidal effect are significantly better than general chemical preservatives. At the same time, L-cysteine ​​can combine with quinone compounds, a key intermediate product of enzymatic browning, to form a colorless and stable cysteine-quinone complex, blocking the polymerization of quinone to generate melanin, and by inhibiting enzymatic browning, strong antioxidant and antibacterial properties, maintaining texture stability to achieve efficient preservation and significantly reducing the amount of chemical additives with its natural and safe characteristics. The treatment method of the present invention can effectively improve the hardness of Agaricus bisporus, delay the loss of moisture of Agaricus bisporus during storage, successfully extend the shelf life of Agaricus bisporus, and improve the chromaticity of Agaricus bisporus after treatment compared with using plasma activated water alone to treat Agaricus bisporus, solve the disadvantage of rapid browning of Agaricus bisporus after activated water treatment, and improve the commercial value of Agaricus bisporus. Plasma activated water synergistic L-cysteine ​​preservation technology provides a solution for the quality and freshness preservation of white varieties of Agaricus bisporus with its high efficiency, safety and environmental protection characteristics. This technology is beneficial to the quality of edible fungi, prolongs the shelf life of storage and long-distance transportation, and can better meet consumers' high requirements for food safety and flavor, enhance the market competitiveness of products, has important economic value and social benefits, and has broad application prospects in the field of edible fungi processing and preservation. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 Schematic diagram of the appearance changes of Agaricus bisporus with different treatments during storage;

[0021] Figure 2 Schematic diagram of the appearance changes of Agaricus bisporus with different treatments during storage;

[0022] Figure 3 The changes of chromaticity value of Agaricus bisporus with different treatments during storage;

[0023] Figure 4 The changes of soluble solids content of Agaricus bisporus with different treatments during storage;

[0024] Figure 5 The changes of moisture content of Agaricus bisporus with different treatments during storage;

[0025] Figure 6 The hardness changes of Agaricus bisporus with different treatments during storage. DETAILED DESCRIPTION

[0026] The plasma-activated water (PAW) is rich in active ingredients such as hydroxyl radicals, peroxide hydrogen, nitrate, nitrite and the like, which can destroy the cell membranes, proteins and DNA of microorganisms. The L-cysteine can be combined with the key intermediate product of enzymatic browning, i.e. quinone compound, to form a colorless stable cysteine-quinone complex, thereby blocking the polymerization of quinone to generate melanin. In the present application, the plasma-activated water and the L-cysteine are used in combination for the quality preservation and fresh-keeping of Agaricus bisporus, which can not only solve the problem of oxidative browning of Agaricus bisporus after the treatment of the activated water, but also will not affect the physical and chemical properties of Agaricus bisporus, thereby prolonging the fresh-keeping time of Agaricus bisporus. In the present application, the Agaricus bisporus is preferably white varieties, including Fumush 78, Fumush 64, and the like.

[0027] The present application also provides a method for the quality preservation and fresh-keeping treatment of Agaricus bisporus by using the plasma-activated water in combination with L-cysteine, which comprises the following steps: soaking the Agaricus bisporus in the plasma-activated water, and then soaking the treated Agaricus bisporus in a 0.05%-0.35% L-cysteine solution, and then refrigerating.

[0028] As an optional embodiment, in the present application, the preparation method of the plasma-activated water comprises the following steps: placing the low-temperature plasma jet device nozzle below the liquid surface of the deionized water by 20-30 cm for discharge treatment for 100-300 s. The distance below the liquid surface of the deionized water is preferably 22 cm, 25 cm, 27 cm or 29 cm. The discharge treatment is preferably 120 s, 150 s, 170 s, 190 s, 200 s, 230 s, 250 s, 270 s or 290 s. In the present application, the power of the low-temperature plasma jet device is 700-800 VA, the working frequency is 20-30 kHz, and the discharge gas is air. As an optional embodiment, the working air pressure of the air is 0.15-0.2 MPa, preferably 0.16 MPa, 0.17 MPa, 0.18 MPa or 0.19 MPa; the flow rate of the air is 25-35 L / min, preferably 27 L / min, 29 L / min, 31 L / min or 33 L / min. After cooling to room temperature, it is ready for use. In the present application, the plasma-activated water is a functional liquid obtained by treating water by gas discharge plasma. During the plasma treatment, various active substances (such as active oxygen, active nitrogen, ozone, hydrogen peroxide and the like) and the changes in the physical and chemical properties of the water body are generated. The PAW is rich in hydroxyl radicals (·OH), hydrogen peroxide (H2O2), nitrate (NO3 - ), nitrite (NO2 -active ingredients such as L-cysteine, which can destroy the cell membrane, protein and DNA of microorganisms, and significantly inhibit the growth of spoilage bacteria (such as Pseudomonas, mold) and pathogenic bacteria (such as Escherichia coli, Salmonella) on the surface of edible fungi. The L-cysteine in the present application is a commercially available product.

[0029] The Agaricus bisporus without mechanical damage and with white fruiting bodies is selected and the roots are cut. The cut Agaricus bisporus is soaked in the plasma-activated water prepared above, and the mass / volume ratio of the Agaricus bisporus to the plasma-activated water is 1: (1-5) g / mL, preferably 1:1 g / mL, 1:2 g / mL, 1:3 g / mL, 1:4 g / mL or 1:5 g / mL. The soaking time in the plasma-activated water is 10-20 min, preferably 13 min, 15 min, 17 min or 19 min. The soaking time in the plasma-activated water in the present application can destroy the cell membrane, protein and DNA of microorganisms, achieve the basic effects of cleaning, preliminary sterilization and preservation, and avoid cell rupture, nutrient loss or soft texture caused by too long soaking time. After being taken out, the soaked Agaricus bisporus is soaked in a 0.05%-0.35% L-cysteine solution, and the L-cysteine solution is preferably 0.05%, 0.10%, 0.15%, 0.20%, 0.25%, 0.30% or 0.35%. The soaking time in the L-cysteine solution is 8-10 min, preferably 8 min, 9 min or 10 min. The soaking time in the L-cysteine in the present application can inhibit the activity of polyphenol oxidase, can combine with the key intermediate product of enzymatic browning, quinone compound, to form colorless stable cysteine-quinone complex, prevent browning, and will not affect the texture or flavor of Agaricus bisporus due to too long time. After the soaking is completed, the Agaricus bisporus is taken out, drained and packaged in a preservation box for cold storage. As an optional embodiment, the preservation box is a polyethylene box.

[0030] The plasma-activated water and L-cysteine can effectively improve the hardness of Agaricus bisporus, delay the oxidation of soluble solids in edible fungi, effectively maintain the color, taste and flavor, and the method is also used for quality preservation of Agaricus bisporus in the present application.

[0031] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application will be described in detail below with examples, but they should not be understood as limiting the scope of protection of the present application.

[0032] In the following examples, the materials, reagents and the like are commercially available unless otherwise specified, and the reagents and consumables involved in the present application can be obtained from commercial channels. If no specific use conditions are specified, they are usually used according to conventional conditions or according to the conditions recommended by the company.

[0033] Example 1

[0034] Method for shelf-life preservation and fresh-keeping of agaricus bisporus by plasma-activated water combined with L-cysteine

[0035] Select agaricus bisporus of Fushen 78 without mechanical injury and white fruiting body, and cut the roots. Prepare plasma-activated water by using an atmospheric pressure cold plasma jet generator (PG-1000Z / D). The atmospheric pressure cold plasma jet generator system power is 800 VA, the working voltage is 220 V, and the working frequency is 20 kHz. Air is used as the discharge gas, the working air pressure is 0.18 MPa, the gas flow rate is 30 L / min, the probe is extended to the discharge position 30 cm below the liquid surface, the treatment time is 100 s, and the temperature is cooled to ambient temperature. Soak 100 g of agaricus bisporus in 100 ml of plasma-activated water for 10 min. Then take it out and soak it in a 0.15% L-cysteine solution for 10 min. After soaking, take it out and drain the water, and then package and seal the film in a 22x13x4 cm polyethylene box for cold storage.

[0036] Example 2

[0037] Method for shelf-life preservation and fresh-keeping of agaricus bisporus by plasma-activated water combined with L-cysteine

[0038] Select agaricus bisporus of Fushen 64 without mechanical injury and white fruiting body, and cut the roots. Prepare plasma-activated water by using an atmospheric pressure cold plasma jet generator (PG-1000Z / D). The atmospheric pressure cold plasma jet generator system power is 800 VA, the working voltage is 220 V, and the working frequency is 20 kHz. Air is used as the discharge gas, the working air pressure is 0.18 MPa, the gas flow rate is 30 L / min, the probe is extended to the discharge position 30 cm below the liquid surface, the treatment time is 200 s, and the temperature is cooled to ambient temperature. Soak 100 g of agaricus bisporus in 100 ml of plasma-activated water for 10 min. Then take it out and soak it in a 0.15% L-cysteine solution for 10 min. After soaking, take it out and drain the water, and then package and seal the film in a 22x13x4 cm polyethylene box for cold storage.

[0039] Example 3

[0040] Method for shelf-life preservation and fresh-keeping of agaricus bisporus by plasma-activated water combined with L-cysteine

[0041] Selecting no mechanical injury, fruiting body white Agaricus bisporus, cutting root processing. Through the atmospheric pressure cold plasma jet generating device (PG-1000Z / D) to prepare plasma activated water, atmospheric pressure low temperature plasma jet device system power 800VA, working voltage 220V, working frequency 20kHz; with air as the discharge gas, working gas pressure is 0.18MPa, gas flow is 30L / min, the probe is extended to the liquid surface below 30cm place discharges, processing time is 300s, and cools to air temperature. Weighing 100g Agaricus bisporus soaked in 200ml plasma activated water for 15min. Then take out, placed in the concentration of 0.15% L-cysteine solution for 10min. After soaking, take out, drain the water, package in 22x13x4cm polyethylene box, seal the film and refrigerate.

[0042] Example 4

[0043] The method for shelf-life and fresh-keeping treatment of Agaricus bisporus by plasma activated water combined with L-cysteine:

[0044] Selecting no mechanical injury, fruiting body white Agaricus bisporus, cutting root processing. Through the atmospheric pressure cold plasma jet generating device (PG-1000Z / D) to prepare plasma activated water, atmospheric pressure low temperature plasma jet device system power 800VA, working voltage 220V, working frequency 20kHz; with air as the discharge gas, working gas pressure is 0.18MPa, gas flow is 30L / min, the probe is extended to the liquid surface below 30cm place discharges, processing time is 100s, and cools to air temperature. Weighing 100g Agaricus bisporus soaked in 200ml plasma activated water for 15min. Then take out, placed in the concentration of 0.15% L-cysteine solution for 8min. After soaking, take out, drain the water, package in 22x13x4cm polyethylene box, seal the film and refrigerate.

[0045] Example 5

[0046] The method for shelf-life and fresh-keeping treatment of Agaricus bisporus by plasma activated water combined with L-cysteine:

[0047] Selecting no mechanical injury, fruiting body white Agaricus bisporus W2000, cut root processing. Plasma activated water was prepared by atmospheric pressure cold plasma jet generator (PG-1000Z / D). The system power of atmospheric pressure cold plasma jet generator was 800 VA, the working voltage was 220 V, and the working frequency was 20 kHz. Air was used as the discharge gas, the working pressure was 0.18 MPa, the gas flow was 30 L / min, the probe was extended to the discharge position 30 cm below the liquid surface, the processing time was 300 s, and the temperature was cooled to ambient temperature. 100 g of Agaricus bisporus was soaked in 200 ml of plasma activated water for 20 min. Then it was taken out and soaked in 0.05% L-cysteine solution for 10 min. After soaking, it was taken out and drained, and then packaged in a 22x13x4 cm polyethylene box and refrigerated.

[0048] Example 6

[0049] Method for shelf-life and fresh-keeping treatment of Agaricus bisporus by plasma activated water and L-cysteine:

[0050] Selecting no mechanical injury, fruiting body white Agaricus bisporus As2796, cut root processing. Plasma activated water was prepared by atmospheric pressure cold plasma jet generator (PG-1000Z / D). The system power of atmospheric pressure cold plasma jet generator was 800 VA, the working voltage was 220 V, and the working frequency was 20 kHz. Air was used as the discharge gas, the working pressure was 0.18 MPa, the gas flow was 30 L / min, the probe was extended to the discharge position 30 cm below the liquid surface, the processing time was 300 s, and the temperature was cooled to ambient temperature. 100 g of Agaricus bisporus was soaked in 300 ml of plasma activated water for 10 min. Then it was taken out and soaked in 0.15% L-cysteine solution for 9 min. After soaking, it was taken out and drained, and then packaged in a 22x13x4 cm polyethylene box and refrigerated.

[0051] Example 7

[0052] Method for shelf-life and fresh-keeping treatment of Agaricus bisporus by plasma activated water and L-cysteine:

[0053] Select W192 Agaricus bisporus with no mechanical damage and white fruiting bodies and cut the roots. Plasma-activated water was prepared using an atmospheric pressure cold plasma jet generator (PG-1000Z / D). The system power was 800VA, the operating voltage was 220V, and the operating frequency was 20kHz. Air was used as the discharge gas, the operating pressure was 0.18MPa, the gas flow rate was 30L / min, and the probe was extended 30cm below the liquid surface. The treatment time was 300s, and the sample was cooled to ambient temperature. Weigh 100g of Agaricus bisporus and soak it in 300ml of plasma-activated water for 10min. Then, remove the sample and soak it in a 0.25% L-cysteine ​​solution for 10min. After soaking, remove the sample, drain the water, and package it in a 22×13×4cm polyethylene box, seal it with film, and refrigerate it.

[0054] Example 8

[0055] Method for preserving the quality and freshness of Agaricus bisporus by using plasma activated water combined with L-cysteine:

[0056] Select A15 Agaricus bisporus with no mechanical damage and white fruiting bodies and cut the roots. Plasma-activated water was prepared using an atmospheric pressure cold plasma jet generator (PG-1000Z / D). The system power was 800VA, the operating voltage was 220V, and the operating frequency was 20kHz. Air was used as the discharge gas, the operating pressure was 0.18MPa, the gas flow rate was 30L / min, and the probe was extended 30cm below the liquid surface. The treatment time was 300s, and the sample was cooled to ambient temperature. Weigh 100g of Agaricus bisporus and soak it in 400ml of plasma-activated water for 10 minutes. Then, remove the sample and soak it in a 0.35% L-cysteine ​​solution for 10 minutes. After soaking, remove the sample, drain the water, and package it in a 22×13×4cm polyethylene box, seal it with film, and refrigerate it.

[0057] Example 9

[0058] Method for treating Agaricus bisporus with plasma activated water combined with L-cysteine ​​to preserve quality and freshness:

[0059] Selecting no mechanical injury, fruiting body white fomes 78 Agaricus bisporus, cutting root processing. Through the atmospheric pressure cold plasma jet generating device (PG-1000Z / D) to prepare plasma activated water, atmospheric pressure low temperature plasma jet device system power 800VA, working voltage 220V, working frequency 20kHz; with air as discharge gas, working air pressure 0.18MPa, gas flow 30L / min, the probe stretches to the liquid surface below 30cm place discharges, processing time 300s, and cooling to empty temperature. Weighing 100g Agaricus bisporus soaking in 300mL plasma activated water for 10min. Then take out, place in the concentration of 0.35% L-cysteine solution for 10min. After soaking, take out, drain, package in 22x13x4cm polyethylene box, seal film and refrigerate.

[0060] Example 10

[0061] The method for shelf life and fresh keeping treatment of Agaricus bisporus by plasma activated water combined with L-cysteine:

[0062] Selecting no mechanical injury, fruiting body white fomes 78 Agaricus bisporus, cutting root processing. Through the atmospheric pressure cold plasma jet generating device (PG-1000Z / D) to prepare plasma activated water, atmospheric pressure low temperature plasma jet device system power 800VA, working voltage 220V, working frequency 20kHz; with air as discharge gas, working air pressure 0.18MPa, gas flow 30L / min, the probe stretches to the liquid surface below 30cm place discharges, processing time 300s, and cooling to empty temperature. Weighing 100g Agaricus bisporus soaking in 300mL plasma activated water for 10min. Then take out, place in the concentration of 0.35% L-cysteine solution for 10min. After soaking, take out, drain, package in 22x13x4cm polyethylene box, seal film and refrigerate.

[0063] Comparative Example 1

[0064] Selecting no mechanical injury, fruiting body white fomes 78 Agaricus bisporus cutting root processing, package in 22x13x4cm polyethylene box, seal film and refrigerate as blank control (CK).

[0065] Comparative Example 2

[0066] The difference with example 1 is only that: abandoning the treatment method of plasma activated water combined with L-cysteine, replacing with sterile water soaking.

[0067] Comparative Example 3

[0068] The difference with example 1 is only that: abandoning L-cysteine soaking, after soaking in plasma activated water, take out, drain, package in 22x13x4cm polyethylene box, seal film and refrigerate.

[0069] Test Example 1

[0070] The Agaricus bisporus of Fushilao 78 with no mechanical damage, white fruiting body and similar shape and size were selected, and were treated and refrigerated according to the method of Example 1 and Comparative Examples 1-3, and were observed by taking pictures every day. The experimental results of Comparative Examples 1-3 are shown in Table 1, Paw is the plasma-activated water treatment group of Comparative Example 3, and the results show that the Agaricus bisporus treated by plasma-activated water only immediately browned on the first day, which seriously affected its commercial value. The experimental results of Example 1 and Comparative Examples 1-2 are shown in Table 2, and the results show that the Agaricus bisporus of Example 1 treated by adding L-cysteine color protection did not change in color on the first day of storage, and browned and dehydrated on the seventh day of storage in Comparative Example 1 and Comparative Example 2, while the Agaricus bisporus of Example 1 still maintained good commercial value, met the needs of consumers for high-quality edible fungi, and improved the market competitiveness of the product. Figure 1 Figure 2

[0071] Test Example 2 Changes in physicochemical properties of Agaricus bisporus treated by plasma-activated water combined with L-cysteine during storage

[0072] Eighteen Agaricus bisporus of Fushilao 78 with no mechanical damage, white fruiting body and similar shape and size were selected, and were randomly selected and treated and refrigerated according to the method of Example 1, Comparative Example 1 and Comparative Example 2, and the physicochemical properties of Agaricus bisporus treated by plasma-activated water combined with L-cysteine during storage were detected.

[0073] 1. Brightness

[0074] The difference in appearance color is an important indicator for judging the storage period of Agaricus bisporus, and a good color also increases the commercial value of Agaricus bisporus. Brightness L* is an indicator of color, and the larger the L* value, the whiter the color of Agaricus bisporus. The brightness (L*) of Agaricus bisporus samples was measured and calculated by WSC-C colorimeter, and the colorimeter was used to measure L* at three fixed different positions on the cap each time. The experimental results are shown in Table 3, and the results show that on the first day of storage, the brightness L* of Agaricus bisporus of Example 1 and Comparative Examples 1 and 2 was similar, and there was no significant difference; on the eleventh day of storage, the brightness L* of Agaricus bisporus of Example 1 did not change significantly and remained between 73-85, while the brightness L* of Agaricus bisporus of Comparative Examples 1 and 2 decreased significantly to 60-70. It is proved that the color protection treatment of the present application Example 1 produces a significant difference (P<0.01) in the brightness of Agaricus bisporus during the storage period compared with Comparative Examples 1-2. Figure 3 2. Soluble solids content (SSC)

[0075] ​​​

[0076] The soluble solids content in edible fungi includes soluble sugar and soluble protein, which is a nutritional indicator. The higher the content, the higher the value.

[0077] SSC content was determined according to the "Determination of Soluble Solids Content in Fruits and Vegetables—Refractometer Method (NY / T 2637-2014)." This method involved selecting each group of Agaricus bisporus samples, mincing them in a high-speed tissue grinder, wrapping them with four layers of gauze of the appropriate size, and squeezing and filtering 2 mL of the liquid into a centrifuge tube. The filtrate was aspirated using a rubber-tipped dropper. The instrument was wiped clean with lens paper and zeroed with distilled water. Two to three drops of the filtrate were evenly distributed on the center of the prism, and the percentage of soluble solids was read at 20°C. Three replicates were performed for each group, and the average value was calculated.

[0078] The experimental results are as follows Figure 4 As shown, there was no significant difference in soluble solids content between Example 1 and Comparative Examples 1-2 during the initial storage period. The soluble solids content of the Agaricus bisporus in Comparative Examples 1 and 2 was higher than that in Example 1, and showed an initial upward and then downward trend. This phenomenon may be due to the initial increase in soluble solids content due to evaporation of water from the Agaricus bisporus. Starting from the fifth day of storage, the soluble solids content of the Agaricus bisporus in Comparative Examples 1 and 2 decreased significantly. There was still no significant difference in soluble solids content in Example 1. However, a significant difference in SSC was observed between Example 1 and Comparative Examples 1-2 (p < 0.01).

[0079] 3. Moisture content

[0080] Moisture content represents the freshness, physiological activity and taste of Agaricus bisporus. When the moisture content is lower than a certain value, the mushroom will shrink and lose its commercial value. The moisture content was determined using the method in GB5009.3-2016. Five replicates were made for each sample and the average value was taken. The experimental results are as follows: Figure 5 As shown, there was no significant difference in moisture content between the Agaricus bisporus of Example 1 and Comparative Examples 1-2 during the early stages of storage. However, from the fifth to the eleventh day of storage, the moisture content of the Agaricus bisporus of Example 1 was significantly higher than that of Comparative Examples 1-2. This may be because Comparative Example 2 had undergone sterile water treatment, which resulted in a high water retention capacity during the initial storage period. After three days of storage, the moisture content of Comparative Examples 1 and 2 decreased significantly, with the moisture loss exceeding 5%, and the Agaricus bisporus had lost its commercial value.

[0081] 4. Hardness

[0082] Hardness, one of the indicators of texture. The greater the hardness, the better the quality of Agaricus bisporus. Agaricus bisporus will become soft and its hardness will decrease in the later storage period. Hardness is measured by TA-XT2i texture analyzer in TPA mode to determine the hardness characteristics of Agaricus bisporus. The test conditions are as follows: probe: P / 6, pre-test speed: 10 mm / sec, test speed: 2 mm / sec, post-test speed: 10 mm / sec, compression ratio: 60%, compression time: 5 sec, trigger force: 5 g, the stipe of Agaricus bisporus is cut to an appropriate height before testing, the probe is aligned with the middle of the cap, and 5 parallel samples are set for each group to take the average value. The experimental results are shown in Table 2. Figure 6 As shown in Table 2, the hardness of Agaricus bisporus of Example 1 and Comparative Examples 1-2 is gradually decreasing during the whole storage period. There is no obvious difference in hardness between Comparative Examples 1-2 and Example 1 on the first day of storage, but then the hardness of Comparative Examples 1 and 2 decreases significantly on the third day of storage, and softening occurs, while the hardness of Example 1 does not change significantly, and Example 1 and Comparative Examples 1-2 begin to show significant differences in hardness. It is shown that the treatment of plasma-activated water of the present application can significantly inhibit the softening of Agaricus bisporus.

[0083] In summary, the treatment of Agaricus bisporus with plasma-activated water combined with L-cysteine does not affect its physicochemical properties during storage, and can effectively maintain the color, taste and flavor of Agaricus bisporus.

[0084] The above description is only an embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the present application specification, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. The application of plasma activated water combined with L-cysteine ​​in the preservation of Agaricus bisporus is characterized in that: The concentration of L-cysteine ​​is 0.05%-0.35%.

2. The use according to claim 1, characterized in that The Agaricus bisporus is a white variety.

3. A method for treating Agaricus bisporus with plasma activated water combined with L-cysteine ​​to preserve quality and freshness, characterized in that: The following steps are involved: The Agaricus bisporus is soaked in plasma activated water, and then the treated Agaricus bisporus is soaked in a 0.05%-0.35% L-cysteine ​​solution and refrigerated.

4. The method according to claim 3, characterized in that The mass volume ratio of Agaricus bisporus to plasma activated water for soaking is 1:(1-5) g / mL, and the Agaricus bisporus is soaked in the plasma activated water for 10-20 min.

5. The method according to claim 3 or 4, characterized in that The method for preparing plasma-activated water comprises the following steps: placing the nozzle of a low-temperature plasma jet device 20 to 30 cm below the liquid surface of deionized water and performing discharge treatment for 10 to 20 minutes.

6. The method according to claim 5, characterized in that The power of the low-temperature plasma jet device is 700-800VA, the operating frequency is 20-30kHz, and the discharge gas is air.

7. The method according to claim 6, characterized in that The working pressure of the air is 0.15-0.2 MPa, and the gas flow rate is 25-35 L / min.

8. The method according to claim 3, characterized in that Soak in the L-cysteine ​​solution for 8 to 10 minutes.

9. The method according to claim 3, characterized in that The refrigerated storage is refrigerated storage in a fresh-keeping box.

10. Use of the method according to any one of claims 3 to 9 in improving the color and taste of Agaricus bisporus.

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