Manufacturing method of food spoilage nanofibrous membrae indicator using Curcumin and Quitertin, and Products thereof

Abstract

The present invention relates to a method for manufacturing a food spoilage nanofiber membrane indicator using curcumin and quercetin and the product thereof, and more specifically, to a method for manufacturing a nanofiber membrane-type indicator by mixing curcumin and quercetin with polyvinyl alcohol and the product thereof.

Description

Technology Field

[0001] The present invention relates to a method for manufacturing a food spoilage nanofiber membrane indicator using curcumin and quercetin and the product thereof, and more specifically, to a method for manufacturing a nanofiber membrane-type indicator by mixing curcumin and quercetin with polyvinyl alcohol and the product thereof. Background Technology

[0002] Recently, the packaging industry has been conducting research and development on packaging materials that satisfy consumer needs by providing various information to end consumers through the development of smart packaging. Such smart packaging includes technology that provides consumers with information about the food by observing changes in the internal and external environment, such as temperature, pH, and microorganisms.

[0003] A representative example is a pH-based indicator technology that detects food spoilage and displays it externally. It is placed inside the food during the process of packaging fresh food using transparent packaging, allowing the condition of the food inside to be visually checked for spoilage without opening the food packaging.

[0004] Conventional pH-based methods provide an indicator by manufacturing a compound of a color change indicator component and a polymer resin component into a film form and placing it inside the packaging. This allows for easy external verification by detecting an increase in the levels of ammonia, trimethylamine (TMA), or carbon dioxide caused by the denaturation of proteins within the packaging, thereby causing a color change.

[0005] However, film-type indicators may have discoloration indicator components leached out due to the humid environment or temperature changes inside the packaging container, and the leached discoloration indicator components may be exposed to the human body through packaged food.

[0006] Korean Registered Patent No. 10-1910014 (registered on October 15, 2018; hereinafter referred to as 'Patent Document 1') presents an indicator for detecting the freshness of food, a method for manufacturing the same, and a method for determining the freshness of food using the same. The said Patent Document 1 presents an indicator by coating a PET film with a coating solution containing a pH indicator and laminating a porous film.

[0007] Korean Registered Patent No. 10-0489489 (registered on May 4, 2005; hereinafter referred to as 'Patent Document 2') presents a polymer compound that changes color according to pH changes and a pH indicator for kimchi using said compound. Patent Document 2 prepares a pH-color-changing polymer compound by mixing a pH-color-changing compound with a resin component, and provides this in the form of a film or a kit with a semipermeable membrane attached, thereby enabling the verification of the degree of kimchi ripeness.

[0008] As such, both Patent Documents 1 and 2 provide indicators in the form of a film or through the lamination of a separate porous film, which results in a low specific surface area, making it difficult to quickly detect spoilage, and there is an inherent risk of human absorption due to the penetration of leached discoloration indicator components into food.

[0009] Therefore, there has been a need for a new type of food inspection indicator that improves reactivity relative to the same size and utilizes harmless natural ingredients as color change indicators to reduce the burden of absorption by leaching. Prior art literature

[0010] Korean Registered Patent No. 10-1910014 (Registered Oct. 15, 2018): Indicator for detecting the freshness of food and method for manufacturing the same, and method for determining the freshness of food using the same Korean Registered Patent No. 10-0489489 (Registered May 4, 2005): Polymer compound that changes color according to pH change and pH indicator for kimchi using the compound The problem to be solved

[0011] The method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin and the product thereof according to the present invention, for solving the problems of the prior art as described above,

[0012] The purpose is to provide a method and product for manufacturing a nanofiber membrane indicator by mixing curcumin extracted from the rhizome of turmeric, a natural substance, and quercetin extracted from fruits or vegetables, based on a biocompatible polymer, polyvinyl alcohol (PVA). means of solving the problem

[0013] The method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin and the product thereof according to the present invention for solving the above problem are,

[0014] A method for manufacturing an indicator for checking food freshness comprises: a step of preparing a spinning solution by mixing ethanol, a resin component polyvinyl alcohol, and a color change indicator component quercetin and curcumin in pure water (DI water); and a step of manufacturing a nanofiber membrane by electrospinning the spinning solution.

[0015] In addition, following the nanofiber membrane manufacturing step, a heat treatment step of heat-treating the manufactured nanofiber membrane may be further performed.

[0016] In addition, in the step of preparing the spinning solution, polyvinyl alcohol, quercetin, and curcumin can be mixed in a ratio of 20-25:1:1.3-1.8 parts by weight.

[0017] In addition, in the step of preparing the spinning solution, the solvent is a mixture of pure water and ethanol in a ratio of 90:10 parts by weight; and in the step of preparing the nanofiber membrane, the spinning conditions may be a spinning solution supply rate of 0.9 mL / h, a spinning distance of 15 cm, a voltage of 22 kV, a relative humidity of 60%, and a temperature of 25°C.

[0018] In addition, the present invention provides an indicator of a food spoilage nanofiber membrane using curcumin and quercetin according to the manufacturing method of the present invention. Effects of the invention

[0019] The method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin according to the means for solving the above problem and the product thereof are, of the present invention

[0020] It is possible to provide a non-toxic, biocompatible indicator by using natural substances such as curcumin and quercetin as discoloration indicator components to detect decay, and by simply mixing and stirring without using toxic organic solvents or crosslinking agents.

[0021] In addition, it is manufactured as a nanofiber membrane by electrospinning, making it more suitable for mass production than the solution molding method, and can enhance food safety by detecting spoilage early through improved colorimetric sensitivity due to increased specific surface area and a porous structure.

[0022] In addition, it has become possible to provide an indicator that offers antioxidant and antibacterial effects, thereby enabling packaged foods to be stored more freshly, and a method for manufacturing the same. Brief explanation of the drawing

[0023] FIG. 1 is a process flow diagram of an indicator manufacturing method according to a preferred embodiment of the present invention. Figure 2 is a photograph showing the color change of a solution of color-changing indicator components used in the present invention according to a change in pH. FIG. 3 is an SEM image of the nanofiber membranes of Example 1 and Comparative Examples 1 to 4 prepared. Figure 4a is a photograph showing the moisture stability of the nanofiber membrane of Example 1, which underwent heat treatment, and the nanofiber membrane of Comparative Example 5, which did not undergo heat treatment. Figure 4b is an SEM image showing the structural change over time of the nanofiber membrane of Example 1 in a humid environment. Figures 5a and 5b are graphs showing the antioxidant activity of Example 1 (PQC), Comparative Example 3 (PVA), and Comparative Example 4 (PQ) measured by DPPH analysis. Figures 6a and 6b are graphs quantifying the diameter of the inhibition zone, which were used to measure the antibacterial activity of Example 1 (PQC), Comparative Example 3 (PVA), and Comparative Example 4 (PQ) by the disk diffusion method. FIGS. 7a and 7b are photographs and quantitative graphs showing the color change over time of the nanofiber membrane (NFM) of Example 1 and the film of Comparative Example 6 using ammonia vapor gas. Figure 8a is a photograph showing the color change when the examples and comparative examples were applied to shrimp spoilage. FIG. 8b is a quantitative graph showing the total color change value (ΔE) of FIG. 8a. Figure 8c is a quantitative graph showing the change in TVB-N values. Specific details for implementing the invention

[0024] The present invention will be described in detail below with reference to the attached drawings. Since the present invention is susceptible to various modifications and may take various forms, specific embodiments are illustrated in the drawings and the invention is described in detail in the text. However, this is not intended to limit the present invention to the specific disclosed forms, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention. Similar reference numerals have been used for similar components in the description of each drawing. In the attached drawings, the dimensions of the structures are depicted enlarged or reduced compared to the actual dimensions for the sake of clarity of the present invention.

[0025] The terms used in this application are used merely to describe specific embodiments and are not intended to limit the invention. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this application, terms such as “comprising,” “having,” or “having” are intended to specify the presence of the features, numbers, steps, actions, components, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, or combinations thereof.

[0026] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms such as those commonly used and defined in advance should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this application.

[0027] FIG. 1 is a process flow diagram of an indicator manufacturing method according to a preferred embodiment of the present invention.

[0028] The method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin according to the present invention comprises a step of manufacturing a spinning solution and a step of manufacturing a nanofiber membrane.

[0029] The above spinning solution preparation step is a step of preparing a spinning solution by mixing curcumin and quercetin as color indicator components with a solvent, using polyvinyl alcohol (PVA), which has biocompatible polymer properties, as the basic resin component.

[0030] The above-mentioned polyvinyl alcohol serves to maintain consistency in the color change reactivity of the product by being used as a binder or acceptor with the color change indicator component.

[0031] The above curcumin is a major component of turmeric and has antioxidant function. It is yellow in color and undergoes a color change in an alkaline environment with a pH of 7 or higher.

[0032] The above quercetin is a type of flavonoid found in various plants, such as fruits, vegetables, and nuts. It is particularly abundant in onion peels and effectively removes free radicals through powerful antioxidant action, thereby delaying cell damage. It also has antibacterial properties that can prevent food contamination and exhibits a color change in alkaline environments with a pH of 7 or higher.

[0033] Therefore, using a color change indicator that combines curcumin and quercetin can increase the shelf life of food and prevent bacterial contamination by providing additional antibacterial functions while maintaining sensitivity to color change.

[0034] Polyvinyl alcohol, quercetin, and curcumin can be mixed in the above mixing ratio in a ratio of 20 to 25: 1: 1.3 to 1.8 parts by weight, and preferably in a ratio of 22: 1: 1.5.

[0035] If the amount of the above polyvinyl alcohol mixed is 22 parts by weight or less, the tensile strength decreases after nanofiber spinning, and if it is mixed in 25 parts by weight or more, the amount of the color change indicator component is low, so the sensitivity to color change due to pH change decreases, so it is desirable to mix within the above range.

[0036] In addition, if the amount of quercetin mixed is 1 part by weight or more, the sterilization efficacy increases, but the degree of discoloration according to pH decreases, making it difficult to quickly visually confirm food spoilage, and if mixed at 1 part by weight or less, the sterilization efficacy decreases, so it is desirable to mix at 1 part by weight.

[0037] In addition, if the amount of curcumin mixed is 1.3 parts by weight or less, the discoloration reaction due to pH change is reduced, making it difficult to quickly detect initial food spoilage; if it is mixed at 1.8 parts by weight or more, the discoloration enhancement effect is insufficient and the amount of leaching increases during use, which may reduce the marketability of the food's appearance and cause bead-shaped granules to form on the nanofiber membrane produced by electrospinning, resulting in reduced air permeability and reduced uniformity of the discoloration reaction, it is desirable to mix and use it within the above range.

[0038] In addition, a solvent is prepared by mixing pure water and ethanol, and a spinning solution for use in electrospinning is prepared by mixing polyvinyl alcohol and a color change indicator component.

[0039] The above ethanol is prepared by mixing pure water and ethanol in a ratio of 85 to 92 parts by weight and 8 to 15 parts by weight, preferably 90 parts by weight.

[0040] If the above-mentioned ethanol is mixed beyond the set range, bead-shaped fibers appear due to the difference in evaporation rates between ethanol and water. That is, during electrospinning, ethanol evaporates first as fibers are formed; however, the water evaporates later, causing bead-shaped fibers to appear, making it difficult to provide uniform reactivity. Furthermore, if mixed below the set range, the dissolution of the modification indicator component is poor, resulting in a disadvantage of uneven distribution in the spinning solution; therefore, it is desirable to mix within the above range.

[0041] In addition, if quercetin is mixed in at least 2 parts by weight with respect to 100 parts by weight of a solvent mixed with pure water and ethanol, bead-shaped nanofibers are formed, and if mixed in at least 1 part by weight, the sterilization effect is reduced, so it is desirable to mix within the above range. Also, if curcumin is mixed in at least 2 parts by weight, bead-shaped fibers are generated. As such, since quercetin and curcumin have low solubility in ethanol, bead-shaped fibers are generated; therefore, it is desirable to mix within the set range to provide uniform sensitivity without bead formation.

[0042] The above nanofiber membrane manufacturing step is a step of manufacturing a nanofiber membrane by electrospinning the prepared spinning solution.

[0043] At this time, the spinning conditions consist of a spinning solution supply rate of 0.9 mL / h, a spinning distance of 15 cm, a voltage of 22 kV, a relative humidity of 60%, and a temperature of 25°C.

[0044] If the supply speed of the spinning solution increases, the diameter of the spun fiber increases and the specific surface area decreases; if the supply speed of the spinning solution decreases, the fiber breaks, making it difficult to produce continuous fibers.

[0045] In addition, if the radiation distance becomes shorter or longer than the set distance, it is difficult to receive the nanofibers.

[0046] In addition, the above voltage, relative humidity, and temperature were applied to a typical electrospinning environment.

[0047] Next, a heat treatment step for heat-treating the nanofiber membrane produced by electrospinning may be further performed.

[0048] The heat treatment step involves treating the nanofiber membrane at a temperature of 150 to 160°C, preferably 155°C, for about 10 minutes to cure the surface of the nanofiber membrane, thereby providing long-term structural stability against moisture exposure.

[0049] Below the set temperature, the heat treatment time increases. Above the set temperature, the structural strength increases excessively, removing elasticity and reducing handling performance. Furthermore, regarding the heat treatment time, if it is shorter than the set time, the surface hardening of the nanofiber membrane does not occur sufficiently, which may lead to decomposition by moisture; if it is longer than the set time, elasticity decreases, resulting in reduced handling performance. Therefore, it is desirable to perform the heat treatment within the above range.

[0050] Figure 2 is a photograph showing the color change of a solution of color-changing indicator components used in the present invention according to a change in pH.

[0051] (a) is a quercetin solution that changes color from a clear state at pH 10 and pH 12.

[0052] (b) showed that curcumin was yellow overall at pH 2–6, changed to orange starting at pH 8, and gradually became darker as the pH increased to 12.

[0053] (c) is a solution mixed with curcumin and quercetin, which changed color stepwise starting from pH 8.

[0054] As noted, it was confirmed that a solution mixed with curcumin and quercetin provides additional antibacterial function of quercetin and exhibits stepwise color change across the entire alkaline range. Therefore, it was confirmed that when used as a freshness indicator for protein foods, it can be used as an indicator that changes color by reacting with ammonia generated during protein spoilage.

[0055] The method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin according to the present invention and the product thereof will be explained in more detail through the following examples.

[0056] Nanofiber membrane manufacturing

[0057] 1) Example 1 (Preparation of PQC 1.5)

[0058] - Preparation of radiation solution

[0059] 22g of polyvinyl alcohol was mixed with 90ml of pure water, stirred at 80℃ for 1 hour, and cooled at room temperature.

[0060] Next, 10 ml of ethanol and 1 g of quercetin were mixed and stirred for 12 hours.

[0061] Next, 1.5g of curcumin was mixed and stirred for 3 hours to prepare a spinning solution.

[0062] - Nanofiber membrane manufacturing

[0063] The manufactured radiating solution was injected into a syringe and mounted on an electrospinning device.

[0064] The discharge distance, which is the distance between the syringe nozzle tip and the collector plate, was set to 15 cm.

[0065] The radiation environment was maintained at a relative humidity of 60% and a temperature of 25℃.

[0066] A voltage of 22 kV was applied to the nozzle tip of the syringe, and the spinning solution was discharged through the syringe pump at a supply rate of 0.9 ml / h to produce a nanofiber membrane.

[0067] - Heat treatment of nanofiber membranes

[0068] The manufactured nanofiber membrane was placed in an oven and heat-treated at 155°C for 10 minutes to produce an indicator nanofiber membrane (PQC1.5).

[0069] 2) Comparative Example 1 (PQC 1 manufacturing)

[0070] A nanofiber membrane (PQC 1) was prepared using the same method as in Example 1, except that a mixture was prepared by mixing 22g of polyvinyl alcohol, 1g of quercetin, and 1g of curcumin.

[0071] 3) Comparative Example 2 (PQC 2 manufacturing)

[0072] A nanofiber membrane (PQC 2) was prepared using the same method as in Example 1, except that a mixture was prepared by mixing 22g of polyvinyl alcohol, 1g of quercetin, and 2g of curcumin.

[0073] 4) Comparative Example 3 (PVA manufacturing)

[0074] A nanofiber membrane (PVA) was prepared in the same manner as in Example 1, except that only 22g of polyvinyl alcohol was mixed into the solvent.

[0075] 5) Comparative Example 4 (PQ manufacturing)

[0076] A nanofiber membrane (PQ) was prepared using the same method as in Example 1, except that a mixture was prepared by mixing 22g of polyvinyl alcohol and 1g of quercetin.

[0077] 6) Comparative Example 5 (Preparation of non-heat-treated PQC 1.5)

[0078] It was manufactured under the same conditions as Example 1, but without performing heat treatment.

[0079] 7) Comparative Example 6 (Preparation of film-type non-radiative PQC 1.5)

[0080] A film was manufactured under the same conditions as in Example 1, but poured into a mold without electrospinning.

[0081] Experimental Example 1 - Measurement of Nanofiber Membrane Structure

[0082] Figure 3 is an SEM image of the nanofiber membranes of Example 1 and Comparative Examples 1 to 4 that were manufactured.

[0083] As referenced, it was confirmed that the average diameter of the nanofibers in the PVA nanofiber membrane (Comparative Example 3) and the PQ nanofiber membrane (Comparative Example 4) was 150 nm and 126 nm, respectively.

[0084] In this regard, PQC1 (Comparative Example 1) and PQC1.5 (Example 1), formed with different amounts of curcumin mixture, showed average nanofiber diameters of 156 nm and 162 nm, respectively, confirming that the nanofiber layer is well distributed and the fiber surface is uniform. However, in PQC2 (Comparative Example 2), it was confirmed that curcumin exists partially in the form of beads, and since the formation of beads reduces the uniformity of discoloration, it is not suitable as an indicator.

[0085] Therefore, PQC1.5 of Example 1 is suitable as an indicator for confirming food spoilage according to the present invention, as it can increase the color change sensitivity by increasing the curcumin content and can provide uniform sensitivity without generating beads.

[0086] Experimental Example 2 - Measurement of Moisture Stability

[0087] Figure 4a is a photograph showing the moisture stability of the nanofiber membrane of Example 1, which was heat-treated, and the nanofiber membrane of Comparative Example 5, which was not heat-treated, and Figure 4b is an SEM photograph showing the structural change over time of the nanofiber membrane of Example 1 in a humid environment.

[0088] Figure 4a shows the nanofiber membrane of Example 1 and the nanofiber membrane of Comparative Example 5 immersed in pure water and photographed at equal time intervals.

[0089] The photograph of the nanofiber membrane in Comparative Example 5 above confirmed that it dissolved rapidly after being immersed in pure water.

[0090] In this regard, the nanofiber photograph in Example 1 below confirmed that it maintained its shape for a long period. Furthermore, it was confirmed that the shape was maintained even when the nanofiber membrane was folded and then unfolded again, indicating that it can be easily handled due to its high elastic recovery force.

[0091] Referring to the photograph in Fig. 4b, Example 1 confirmed that the porosity of the nanofiber is maintained for up to 12 hours, confirming that the function as an indicator for detecting food spoilage can be maintained for a long time.

[0092] Experimental Example 3 - Antioxidant Measurement

[0093] Figures 5a and 5b show the antioxidant activity of Example 1 (PQC), Comparative Example 3 (PVA), and Comparative Example 4 (PQ) measured through DPPH analysis.

[0094] DPPH (2,2-diphenyl-1-picrylhydrazyl) was used as the analysis solution, and measurements were taken using a UV-Vis spectrophotometer after 60 minutes.

[0095] Referring to Fig. 5a, at the maximum peak of DPPH at 517 nm, it was confirmed that Example 1 (PQC) showed a significantly lower absorbance value than Comparative Example 3 (PVC) and Comparative Example 4 (PQ).

[0096] Referring to the graph showing the antioxidant power in Fig. 5b, it was confirmed that Example 1 (PQC) of the present invention provides higher antioxidant power than Comparative Example 4 (PQ), which is a mixture of polyvinyl alcohol and quercetin.

[0097] Therefore, it was confirmed that when curcumin and quercetin are used in combination as color change indicators, the antioxidant capacity is increased, which can further extend the shelf life of food.

[0098] Experimental Example 4 - Antibacterial Measurement

[0099] Figures 6a and 6b are graphs quantifying the diameter of the inhibition zones in photographs measuring the antibacterial activity of Example 1 (PQC), Comparative Example 3 (PVA), and Comparative Example 4 (PQ) by the disk diffusion method.

[0100] Gram-negative E. coli ( E.coil ) and Gram-positive bacterium Staphylococcus aureus ( S. aureus Each of the samples was uniformly spread onto a Petri dish coated with a culture medium and dried, and the nanofiber membranes of Example 1 (PQC), Comparative Example 3 (PVA), and Comparative Example 4 (PQ) were arranged at regular intervals and cultured, and the diameter of the inhibition zone was measured.

[0101] Referring to Fig. 6a, it was confirmed that Comparative Example 3 (PVA) had no inhibition against Escherichia coli and Staphylococcus aureus, while Example 1 (PQC) and Comparative Example 4 (PQ) provided similar inhibitory power against Escherichia coli and Staphylococcus aureus.

[0102] Referring to Fig. 6b, both Example 1 (PQC) and Comparative Example 4 (PQ) had similar inhibition zone diameters, and regarding Staphylococcus aureus, Example 1 (PQC) had a slightly larger inhibition zone diameter than Comparative Example 4 (PQ).

[0103] Therefore, it can be confirmed that Example 1, which contains both quercetin and curcumin, provides superior antibacterial activity.

[0104] Experimental Example 5 - Measurement of Color Change Due to Spoilage

[0105] Figures 7a and 7b are photographs and quantitative graphs showing the color change over time of the nanofiber membrane (NFM) of Example 1 and the film of Comparative Example 6 using ammonia vapor gas.

[0106] The nanofiber membrane (NFM) of Example 1 and the film of Comparative Example 6 were exposed to ammonia vapor gas in an environment of 25°C and 60% relative humidity, and the color change per hour was observed.

[0107] As seen in Fig. 7a, it can be seen that the nanofiber membrane NFM of Example 1 is more sensitive to color change even by visual inspection, and as shown in Fig. 7b, it can be seen that the total color change value (ΔE) is also higher for the nanofiber membrane NFM of Example 1.

[0108] This confirms that nanofiber membranes, with a specific surface area increased by porosity rather than film form, appear more sensitive to color changes.

[0109] Figure 8a is a photograph showing the color change when the examples and comparative examples were applied to shrimp spoilage.

[0110] Example 1 (PQC NFM), Comparative Example 3 (PVA), Comparative Example 4 (PQ), and Comparative Example 6 (PQC film) were placed together with shrimp, and an initial photograph and a photograph taken after 24 hours were shown. As referenced, it was confirmed that the most distinct color change occurred in Example 1 (PQC NFM).

[0111] Figure 8b is a quantitative graph showing the total color change value (ΔE) of Figure 8a. As noted, Comparative Example 3 (PVA) has a Delta E value of less than 5, making visual identification impossible, whereas Comparative Example 4 (PQ), Comparative Example 6 (PQC film), and Example 1 (PQC NFM) are visually identifiable. Additionally, Comparative Example 6 (PQC film) and Example 1 (PQC NFM) show a Delta E value of 12 or higher, indicating that the ability to distinguish between colors is enhanced. Furthermore, since Example 1 (PQC NFM), which has a higher specific surface area, possesses superior color sensitivity compared to Comparative Example 6 (PQC film), it can be seen that it is more suitable as a food spoilage indicator.

[0112] Figure 8c is a quantitative graph showing the change in TVB-N values. As noted, the TVB-N (Total Volatile Basic Nitrogen) value was found to be above 20 mg / 100g, the standard for shrimp spoilage, in just one day, confirming that shrimp spoilage had occurred after 24 hours. This confirms that the measurement was taken in the state of shrimp spoilage shown in Figure 8a.

[0113] As described above, the nanofiber membrane used as an indicator for confirming food spoilage according to the present invention provides a high specific surface area and porosity through electrospinning and heat treatment of a solution of polyvinyl alcohol mixed with quercetin and curcumin, thereby improving reaction sensitivity and enabling the provision of a useful indicator manufacturing method and product that can maintain function for a long time even in a humid environment.

Claims

Claim 1 A method for manufacturing an indicator for checking food freshness, comprising: a step of preparing a spinning solution by mixing ethanol, a resin component (polyvinyl alcohol), and a color change indicator component (quercetin and curcumin) in pure water (DI water) to prepare a spinning solution; and a step of manufacturing a nanofiber membrane by electrospinning the spinning solution to produce a nanofiber membrane. Claim 2 A method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin, characterized in that, in claim 1, a heat treatment step of heat-treating the manufactured nanofiber membrane is further performed after the nanofiber membrane manufacturing step. Claim 3 A method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin, characterized in that, in the step of manufacturing the spinning solution according to claim 1, polyvinyl alcohol, quercetin, and curcumin are mixed in a ratio of 20-25:1:1.3-1.8 parts by weight. Claim 4 A method for manufacturing an indicator of a food spoilage nanofiber membrane using curcumin and quercetin, characterized in that, in the step of manufacturing the spinning solution, ethanol is mixed with pure water and ethanol in a ratio of 90:10 by weight, and in the step of manufacturing the nanofiber membrane, the spinning conditions are a spinning solution supply rate of 0.9 mL / h, a spinning distance of 15 cm, a voltage of 22 kV, a relative humidity of 60%, and a temperature of 25˚C. Claim 5 An indicator of a food spoilage nanofiber membrane using curcumin and quercetin prepared by the manufacturing method of claims 1 to 4.

Images