Nanofiber and application thereof in fishy smell substance removal

Abstract

The invention discloses a nanofiber and application thereof in fishy smell substance removal, and belongs to the technical field of new materials. According to the invention, an electrostatic spinning method is combined with a crosslinking modification technology, PVA, KGM and TA are combined, tannic acid is introduced as a crosslinking agent, an intermolecular crosslinking bond is formed between PVA and KGM, and the prepared PVA / KGM / TA nanofiber is used as a substrate of an adsorption material. The porous starch capable of adsorbing volatile compounds is further doped, so that the adsorption of the nanofiber to bad fishy smell substances is improved.

Description

Technical Field

[0001] This invention relates to a nanofiber and its application in the removal of fishy-smelling substances, belonging to the field of new materials technology. Background Technology

[0002] Kelp (Lamimaria japonica) belongs to the brown algae family and is a perennial, large edible algae. Its leaves are long and narrow, reaching up to 6 meters in length and 50 centimeters in width. The leaves are olive-green in color and gradually thin from the center to the edges. Kelp is rich in various nutrients, including polysaccharides, dietary fiber, high-quality protein, and bioactive substances with physiological regulatory functions, such as essential amino acids, omega-3 fatty acids, polyphenols, and vitamins. Furthermore, as an important source of iodine, kelp consumption can effectively prevent iodine deficiency and participate in the synthesis of thyroid hormones, exhibiting significant health benefits. It is a widely consumed "longevity food" in East Asia.

[0003] However, the fishy odor of kelp has become a key bottleneck restricting the expansion and upgrading of its processed products industry. A deeper investigation reveals that its causes are mainly related to its living environment and metabolic activities. On the one hand, actinomycetes and other microorganisms in the water produce terpene derivatives during their metabolic activities. These substances can adhere to the surface of algae and be absorbed and accumulated, forming compounds with an earthy odor, ultimately affecting the flavor and quality of algae products. On the other hand, under the catalysis of lipoxygenase, the oxidative decomposition of unsaturated fatty acids in algae first generates unstable primary metabolites. These intermediate products further degrade, subsequently decomposing into volatile substances such as aldehydes, ketones, and acids, which together constitute the main components of the fishy odor of algae. The fishy odor components of seaweed are diverse, structurally complex, and present in low concentrations. Therefore, how to efficiently remove the fishy odor from seaweed has become one of the key common technical challenges restricting the high-value development of seaweed resources.

[0004] Currently, methods for removing fishy odors can be mainly divided into physical deodorization, chemical deodorization, biological deodorization, and combined deodorization. Physical deodorization improves food flavor through adsorption, masking, and encapsulation. The special structure of the deodorizing agent effectively eliminates or masks fishy odor components in food. Chemical deodorization selectively removes fishy odor substances based on their chemical properties, using antioxidants, acids, alkalis, salts, ozone, or organic solvents. However, chemical deodorization produces chemical residues and poses certain hazards, so it is gradually being replaced by safer methods. Biological deodorization utilizes microbial fermentation and enzymatic reactions to remove fishy odors. Therefore, there is a need to develop a method that has less impact on seaweed but effectively removes fishy odors.

[0005] In the study of deodorizing aquatic products, nanofibers can serve as highly efficient adsorbents or functional carriers, effectively removing fishy odor substances through mechanisms such as physical adsorption or chemical degradation, thereby significantly improving the edible quality of the products. By controlling the pore structure and surface properties of nanofibers, selective adsorption and efficient removal of fishy odor components can be achieved. Porous starch (PS), as a safe and economical adsorbent, is widely used in food processing, pharmaceutical manufacturing, and environmental remediation. Its excellent adsorption performance and controllable release characteristics are increasingly becoming a research hotspot. Starch can interact with small molecules such as volatile compounds, which are then encapsulated in starch helices through hydrophobic bonds in these complexes. Therefore, starch is suitable as a carrier for aroma encapsulation and has the potential to act as an aroma adsorbent. Therefore, this invention prepares PS from corn starch via enzymatic hydrolysis-ultrasound. PS is incorporated into a polyvinyl alcohol / konjac glucomannan / tannic acid (PVA / KGM / TA) blend system as the research object. PS / PVA / KGM / TA nanofibers are obtained through electrospinning, exhibiting good adsorption effects on fishy odor substances in kelp. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention employs electrospinning combined with cross-linking modification technology to combine PVA, KGM, and TA, and introduces tannic acid (TA) as a cross-linking agent to form intermolecular cross-linking bonds between PVA and KGM. The resulting PVA / KGM / TA nanofibers serve as the substrate for the adsorption material. The incorporation of porous starch, which adsorbs volatile compounds, further enhances the adsorption of unpleasant odor substances by the nanofibers.

[0007] This invention is achieved through the following technical solution: The first objective of this invention is to provide a method for preparing nanofibers, comprising the following steps: S1. Dissolve polyvinyl alcohol in water to obtain a polyvinyl alcohol solution; add tannic acid to the konjac glucomannan solution to obtain a konjac glucomannan solution containing tannic acid; S2. Mix the polyvinyl alcohol solution and the konjac glucomannan solution containing tannic acid at a weight ratio of 15-25:1, heat and stir until uniform to obtain a polyvinyl alcohol / konjac glucomannan / tannic acid dispersion. S3. The starch suspension of 25-35% is subjected to ultrasonic treatment. After ultrasonic treatment, it is subjected to enzymatic hydrolysis by α-amylase and saccharifying enzyme. After enzymatic hydrolysis, the enzymes are removed. Then the sediment is dried and ground to obtain porous starch. S4. The porous starch prepared in step S3 is processed according to 2-8 wt % is added to the polyvinyl alcohol / konjac glucomannan / tannic acid dispersion prepared in step S2, and stirred evenly to obtain an electrospinning solution; S5. Electrospin the electrospinning solution to obtain the nanofibers.

[0008] In one embodiment of the present invention, the mass concentration of polyvinyl alcohol in the polyvinyl alcohol solution is 6-10. wt %.

[0009] In one embodiment of the present invention, the mass concentration of konjac glucomannan in the konjac glucomannan solution is 0.5-2%. wt %.

[0010] In one embodiment of the present invention, the amount of tannic acid added is 2-4 mg / g based on the mass of the konjac glucomannan solution.

[0011] In one embodiment of the present invention, in step S2, the heating temperature is 80-90 °C.

[0012] In one embodiment of the present invention, in step S3, the starch suspension is obtained by dissolving corn starch in a citrate-disodium hydrogen phosphate buffer solution.

[0013] In one embodiment of the present invention, the ultrasound is performed in an ultrasound machine with a power of 300-500 W and a frequency of 10-30 kHz for 20-40 min.

[0014] In one embodiment of the present invention, enzymatic hydrolysis is performed by adding 1-2% of a complex enzyme of α-amylase and saccharifying enzyme in a ratio of 1:1-3 (based on the starch mass) for 10-15 hours.

[0015] In one embodiment of the present invention, the starch suspension is enzymatically hydrolyzed and then centrifuged at 4000-5000 rpm for 10-20 min, and washed with ultrapure water to remove residual enzymes.

[0016] In one embodiment of the present invention, in step S3, drying is performed at 50-60 °C for 15-30 h.

[0017] In one embodiment of the present invention, in step S3, the ground material is sieved through an 80-120 mesh sieve.

[0018] In one embodiment of the present invention, in step S4, the stirring is carried out at 20-30°C for 10-20 h.

[0019] In one embodiment of the present invention, the nanofibers after electrospinning are dried at 35-45°C for 20-30 hours.

[0020] A second objective of this invention is to provide nanofibers prepared by the aforementioned preparation method.

[0021] A third objective of this invention is to provide the application of the nanofibers in the removal of fishy odor substances from aquatic products.

[0022] In one embodiment of the present invention, the aquatic product is kelp.

[0023] The beneficial effects of this invention are: (1) This application provides a nanofiber prepared by electrospinning, which has a strong adsorption capacity for fishy substances, forms a dense network pore structure, has a large specific surface area and high porosity, which is beneficial for the adsorption of fishy substances. (2) Nanofibers are used as adsorbents in the solid encapsulation deodorization method to adsorb and deodorize the odorous substances in kelp. Compared with the existing adsorption method using activated carbon, nanofibers have the advantages of easy separation, no residue, and better deodorization effect. (3) Distilled water is used as a solvent in the electrospinning process and no other chemical reagents are added. The nanofibers prepared have high safety and have good application prospects in the deodorization treatment of aquatic products. This invention employs electrospinning combined with crosslinking modification technology to combine PVA, KGM, and TA, and introduces tannic acid (TA) as a crosslinking agent to form intermolecular crosslinks between PVA and KGM. The prepared PVA / KGM / TA nanofibers serve as the substrate for the adsorption material. The incorporation of porous starch, which adsorbs volatile compounds, further enhances the adsorption of unpleasant odor substances by the nanofibers. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 SEM images of nanofibers with different PVA contents (a): 5 wt % PVA; (b): 6 wt % PVA; (c):7 wt % PVA; (d): 8 wt % PVA); Figure 2SEM images of PKT nanofibers with different TA contents: (a): PK; (b): PKT-1; (c): PKT-2; (d): PKT-3; (e): PKT-4); Diameter distribution of PKT nanofibers with different TA contents: (f): PK; (h): PKT-2; (i): PKT-3; (j): PKT-4). Figure 3 (a) TGA curves of PVA, PK, and PKT nanofibers; (b) DTG curves. Figure 4 It is WCA nanofiber composed of PVA, PK, and PKT; Figure 5 This is a SEM image of porous starch; Figure 6 This is a SEM image of PS / PVA / KGM / TA nanofibers. Detailed Implementation

[0026] The present invention will be further illustrated below with specific examples. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0027] Source of raw materials Konjac glucomannan (KGM), with a specification of ≥95%, was purchased from Zhaotong Sanai Organic Konjac Development Co., Ltd. Polyvinyl alcohol-124 (PVA), ≥99%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Tannic acid (TA), analytical grade, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; Corn starch, ≥ 99%, purchased from Shanghai Maclean Biochemical Technology Co., Ltd. α-Amylase, 40,000 U / g, purchased from Beijing Solarbio Science & Technology Co., Ltd. Aminoglycoside enzyme, 100,000 U / g, purchased from Beijing Solarbio Science & Technology Co., Ltd. Citric acid, analytical grade, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Disodium hydrogen phosphate dodecahydrate, analytical grade, purchased from Sinopharm Chemical Reagent Co., Ltd. Carboxymethyl chitosan (CMCS), with a degree of deacetylation ≥80%, was purchased from Haialadin Biochemical Technology Co., Ltd. Carrageenan (CAR) was purchased from Haialadin Biochemical Technology Co., Ltd. Soy protein isolate, purchased from Dulai Biotechnology Co., Ltd. β-Cyclodextrin was purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Methanol, analytical grade, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd. Ethanol, analytical grade, purchased from Sinopharm Chemical Reagent Co., Ltd. Cyclohexanone, ≥ 99.5%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.; The kelp was purchased from Fujian Yiyuan Marine Food Co., Ltd.

[0028] The technical solution of the present invention will be described in detail below with reference to specific embodiments. In the following embodiments, unless otherwise specified, the reagents, materials and equipment used can be purchased commercially, prepared by conventional methods, or commonly used in the industry.

[0029] Example 1: This embodiment provides a nanofiber prepared from PVA, KGM, and TA via electrospinning. The preparation of the nanofiber specifically includes the following steps: S1. Accurately weigh 1 g, 1.2 g, 1.4 g, and 1.6 g of PVA powder, and dissolve them in 19 g, 18.8 g, 18.6 g, and 18.4 g of ultrapure water, respectively. Then, place the solutions in an 85°C water bath and stir continuously for 4 hours to obtain a final concentration of 5. wt %, 6 wt %, 7 wt % and 8 wt % PVA spinning solution.

[0030] Figure 1 These are scanning electron microscope images of nanofibers with different PVA concentrations, created by... Figure 1 It can be seen that when the PVA content is low (5... wt %-6 wt At % w / v, due to insufficient polymer chain entanglement, the resulting fibers exhibit a bead-like, uneven structure. Figure 1 (a and b). Increasing the PVA ratio resulted in a more stable spinning process, successfully obtaining ultrafine fibers with uniform diameter and no defects. Figure 1 (c and d). Based on this, 8 was ultimately selected. wt Nanofibers were prepared from %PVA spinning solution and denoted as PVA nanofibers, which were then used in subsequent experimental studies.

[0031] S2. Dissolve 8 g of PVA in 92 mL of ultrapure water, then place in a water bath at 85°C and stir for 4 h to prepare a PVA solution (8 g PVA). wt%). Dissolve KGM (1 g) in 99 mL of ultrapure water and stir at room temperature for 2 hours (1 %). wt % KGM solution). TA was added to the KGM solution at concentrations of 1, 2, 3, and 4 mg / g (w / w, based on the mass of the KGM solution) and stirred for 2 h to obtain KGM solutions containing 1, 2, 3, and 4 mg / g TA. PVA and KGM solutions (including KGM solutions containing TA) were mixed at a weight ratio of 20:1 and magnetically stirred in a water bath at 85°C for 2 h to form a homogeneous spinning solution, designated as PK, PKT-1, PKT-2, PKT-3, and PKT-4 spinning solutions, respectively.

[0032] S3. The electrospinning solution prepared in S2 was electrospinned. The spinning solution was injected into a 20 ml syringe, and a 20 G metal needle was selected as the spinning nozzle. Other parameters included: voltage +18 kV, feed speed 0.05 mm / min, nozzle-to-receiving roller distance 16 cm, temperature 25℃, and relative humidity 55±5%. After spinning, the collected fibers were dried at 40℃ for 24 h to ensure complete solvent evaporation, and were designated as PK, PKT-1, PKT-2, PKT-3, and PKT-4 nanofibers, respectively.

[0033] Figure 2 Scanning electron micrographs of nanofibers with different TA addition amounts, by Figure 2 It was found that the morphology of the nanofibers changed after the addition of KGM solution, with the average diameter changing from 398.08±44.45 nm to 335.1±85.12 nm. The addition of tannic acid led to entanglement and cross-linking of PVA and KGM, forming more entanglement and a denser pore distribution, which enhanced the mechanical properties of the nanofibers. Furthermore, with increasing TA concentration, the obtained fiber diameter became more uniform and finer. When the TA content was 3 mg / g (based on KGM solution), the average diameter reached 261.45±39 nm. However, as the TA content increased further, the average diameter decreased from... Figure 2 In (e), it can be clearly seen that the fiber thickness distribution is significantly uneven and there is a "beading" phenomenon. The molecules interact with KGM through hydrogen bonds and other interactions to form local aggregates. These aggregates affect the uniformity of the spinning solution during electrospinning, making the distribution of pores uneven.

[0034] Figure 3 To assess the thermal stability of different nanofibers, the thermal properties of nanofiber membranes reflect their ability to remain stable at high temperatures. The thermal stability of PVA, PK, and PKT nanofibers was investigated using TGA and DTG plots. The TGA curves present the complete process of membrane thermal decomposition, while the DTG curves represent the rate changes of the thermal decomposition reaction. Figure 3From the TGA curves in (a), the weight loss of nanofibers exhibits three stepwise stages: (i) 30-100℃, weight loss due to water evaporation caused by the breaking of intermolecular hydrogen bonds on the nanofiber surface; (ii) 100-430℃, weight loss caused by the thermal decomposition of the side chain groups and main chain of the polymer PVA. With increasing TA content, the curve for PKT nanofibers shifts upwards, indicating that the addition of TA can partially improve the thermal stability of PVA / KGM-based fibers. The addition of TA leads to the formation of intermolecular hydrogen bonds between the three components, increasing the number of hydrogen bonds within the nanofiber membrane and enhancing its thermal stability. The polyphenolic structure of TA contributes to improved thermal stability. (iii) In the 430-600℃ stage, weight loss is attributed to the carbonization of the material. Figure 3 From the DTG curves in (b), the highest decomposition temperatures of PVA, PK, PKT-1, PKT-2, PKT-3, and PKT-4 nanofibers were 306℃, 298℃, 309℃, 320℃, 323℃, and 314℃, respectively, with residual masses of 9.62%, 0.06%, 0.17%, 4.26%, 0.11%, and 3.42%, respectively. PKT-3 exhibited the highest thermal degradation temperature and the lowest residual mass, which may be related to its loose, uniform, and porous microstructure. During thermal decomposition, the internal substances are more easily exposed to the thermal environment, accelerating the decomposition process and resulting in a more complete decomposition and a lower residual mass. Simultaneously, this structure facilitates the diffusion and escape of subsequent odor molecules.

[0035] Figure 4 The surface wettability test results for different nanofibers are shown. The surface wettability of PVA, PK, and PKT nanofibers is reflected by the water contact angle (WCA). Nanofibers with a WCA less than 90° exhibit hydrophilicity, while those with a WCA greater than 90° exhibit hydrophobicity. Figure 4 As shown, due to the large number of hydroxyl groups on the PVA molecular chains within these fibers, pure PVA nanofibers exhibit hydrophilicity, with a water contact angle of approximately 52.5°. The introduction of KGM and TA increases the contact angle to 64.9° and 64.8°, respectively. With increasing TA content, the contact angle also increases; when the TA content reaches 3 mg / g, the contact angle of PKT-3 reaches approximately 82.8°. However, when the TA content increases further, the contact angle decreases. This is because excessive TA content can damage the fiber integrity. Excessive TA accumulation on the fiber surface leads to agglomeration of the surface structure, disrupting the original rough hydrophobic structure. Excessive TA may alter the interaction balance between PVA and KGM molecules, exposing hydrophilic groups and increasing the hydrophilicity of the fiber surface, thus reducing the contact angle. Based on this, 8 mg / g of KGM was ultimately selected. wt Nanofibers were prepared using %PVA spinning solution and further applied to subsequent experimental studies. Based on this, PKT-3 spinning solution was ultimately selected for further experimental research.

[0036] Example 2: This embodiment provides a porous starch (PS) prepared using an enzymatic hydrolysis-ultrasound method. Specifically, it includes the following steps: S1. Dissolve corn starch (30 g) in citrate-disodium hydrogen phosphate buffer solution (100 mL, pH 5.5) to form a 30% (w / v) starch suspension.

[0037] S2. Use an ultrasonic machine with a power of 400 W and a frequency of 20 kHz to ultrasonically treat the starch suspension for 30 min, and then place the suspension on a 55℃ oscillator (200 rpm) for preheating for 15 min. S3. Add α-amylase and saccharifying enzyme in a ratio of 1:2, with the two accounting for 1.5% of the starch mass, to the above starch suspension for hydrolysis for 12 h, and finally add 5 mL of 95% ethanol solution to stop the enzymatic hydrolysis. S4. Centrifuge the mixed solution at 4500 rpm for 15 min, and wash three times with ultrapure water to remove residual enzymes. Dry the sediment at 55°C for 24 h, then grind the PS and sieve it through a 100-mesh sieve, and store it in a sealed container.

[0038] Figure 5 The scanning electron microscope image of the PS provided in this embodiment is from... Figure 5 It is known that the entire PS particle is full of pores, which can be used as an adsorbent to remove the fishy smell of kelp. Starch can interact with small molecules such as volatile compounds. The volatile compounds are trapped in the starch helix through the hydrophobic bonds in these complexes. Therefore, starch is suitable as a carrier for aroma encapsulation.

[0039] Example 3: This embodiment provides a PS-doped nanofiber, which is prepared by electrospinning of PS, PVA, KGM, and TA. The preparation of the PS-doped nanofiber specifically includes the following steps: S1. The PS obtained in Example 2 is prepared according to 8... wt % (w / w, based on the mass of the PKT-3 solution) was added to the PKT-3 spinning solution prepared in Example 1, and stirred at 25°C for 12 h to obtain the electrospinning solution; S2. The electrospinning solution prepared above is subjected to electrospinning. The spinning solution is injected into a 20 mL syringe, and a 20 G metal needle is selected as the spinning nozzle. Other parameters include: voltage +18 kV, feed speed 0.05 mm / min, nozzle-to-receiving roller distance 16 cm, temperature 25℃, and relative humidity 55±5%. After spinning, the collected fibers are dried at 40℃ for 24 h to ensure complete solvent evaporation, resulting in PS-incorporated nanofibers.

[0040] Figure 6 The scanning electron fiber microscopy image of the PS-doped nanofibers provided in this embodiment is obtained by... Figure 6 It is known that the PS-doped nanofibers are composed of nanoscale fibers, forming a dense network pore structure inside, and porous starch is embedded on the surface. Compared with the nanofibers provided in Example 1, they have a richer pore structure. The nanofibers prepared by the method provided in Example 3 have a larger specific surface area and higher porosity than the nanofibers prepared by the method provided in Example 1, which is beneficial for the adsorption of fishy substances.

[0041] Comparative Example 1: Aerogels prepared from konjac glucomannan and carboxymethyl chitosan for deodorizing kelp include the following steps: Konjac glucomannan and carboxymethyl chitosan were used to prepare composite aerogels in different proportions. KGM and CMCS were dissolved in deionized water at different mass ratios (1:1, 1:2, 1:3) and magnetically stirred until completely dissolved to form a homogeneous solution. Gel molding: The mixed sol was poured into a mold, allowed to stand to form a hydrogel, and then pre-frozen at -80℃ for 12 h, followed by freeze drying at -80℃ for 24 h to obtain KGM / CMCS composite aerogel fibers. The aerogels with different proportions were abbreviated as KC1, KC2, and KC3.

[0042] Comparative Example 2: An adsorbent carrier was prepared using konjac glucomannan and konjac glucomannan / carrageenan (KC) for deodorizing kelp, specifically including the following steps: The gel was prepared using the sol-gel method. A gel solution with a concentration of 0.01 g / mL was prepared according to a KGM:KC ratio of 4.5:5.5. 0.5% β-cyclodextrin (β-CD) and a certain amount of soy protein isolate (SPI) were added (SPI concentrations of 0.3%, 0.5%, and 0.7% were added). The mixture was stirred at 75℃ and 400 rpm for 45 min. After stirring, the mixture was allowed to cool to room temperature to form a gel. The gel was then frozen at -18℃ for 12 h and then frozen in a freeze dryer at -80℃ for 24 h to obtain adsorbents labeled KCSC-1, KCSC-2, and KCSC-3, respectively.

[0043] Comparative Example 3: The specific steps for removing the fishy smell from kelp include: Adjust the amount of PS used in Example 3, and mix the PS obtained in Example 2 according to 2... wt %, 4 wt %, 6 wt % (w / w, based on the mass of the PKT-3 solution) was added to the PKT-3 spinning solution. Other steps and parameters were the same as in Example 3, and nanofibers were obtained by following the steps in Example 3.

[0044] Test example: After grinding the kelp, it was passed through a 60-mesh sieve. Using solid-phase adsorption, the kelp sample and the materials prepared in Examples 1 and 3 and Comparative Examples 1-3 were placed in a 20 mL headspace bottle at a mass ratio of 1:0.4. After sealing, the mixture was reacted in a constant temperature environment of 65℃ for 60 min. After separation, the deodorized kelp was obtained.

[0045] The deodorization rate of the materials prepared in Examples 1 and 3, and Comparative Examples 1-3, was determined. The specific steps are as follows: Deodorization rate: Accurately weigh 1 g of kelp before and after deodorization into 20 mL headspace vials, and quickly tighten the caps. Place a solid-phase microextraction needle (50 / 30 μm, Supelco, USA) in the headspace of the sample vial and perform adsorption at a constant temperature of 25±1℃ for 30 min. The content of odorous substances in the kelp before and after deodorization was determined using a Shimadzu QP-2030 Plus gas chromatography-mass spectrometry system (Japan). 前 With C 后 .

[0046] Calculate the deodorization rate: Deodorization rate (%) = (C 前 C 后 ) / C 前 ×100% The results are shown in Table 1: Table 1

[0047] The results showed that in Example 1, the deodorization rate of kelp using PVA / KGM / TA nanofibers was 83.25%. The deodorization rates of KC1, KC2, and KC3 in Comparative Example 1 were 38.62%, 49.38%, and 62.76%, respectively; the deodorization rates of KCSC-1, KCSC-2, and KCSC-3 in Comparative Example 2 were 29.01%, 29.98%, and 20.75%, respectively; and the deodorization rates of 2 wt% PS / PVA / KGM / TA, 4 wt% PS / PVA / KGM / TA, and 6 wt% PS / PVA / KGM / TA in Comparative Example 3 were 87.97%, 91.15%, and 89.65%, respectively. In comparison, the nanofibers used in Example 3 showed a more significant adsorption effect on the kelp odor, achieving an adsorption rate of 93.21%. This indicates that nanofibers prepared by electrospinning PS, PVA, KGM, and TA have a better deodorizing effect on kelp when they have a good morphological structure.

[0048] In conclusion, using PS-infused nanofibers to deodorize kelp can efficiently remove fishy odor substances with small dosages, opening up a new avenue for deodorization technology in functional aquatic foods.

[0049] The embodiments provided above are not intended to limit the scope of the invention, nor are the described steps intended to limit the order of execution. Any obvious modifications made to the invention by those skilled in the art based on existing common knowledge also fall within the scope of protection defined by the claims.

Claims

1. A method for preparing nanofibers, characterized in that, Includes the following steps: S1. Dissolve polyvinyl alcohol in water to obtain a polyvinyl alcohol solution; add tannic acid to the konjac glucomannan solution to obtain a konjac glucomannan solution containing tannic acid; S2. Mix the polyvinyl alcohol solution and the konjac glucomannan solution containing tannic acid at a weight ratio of 15-25:1, heat and stir until uniform to obtain a polyvinyl alcohol / konjac glucomannan / tannic acid dispersion. S3. The starch suspension of 25-35% is subjected to ultrasonic treatment. After ultrasonic treatment, it is subjected to enzymatic hydrolysis by α-amylase and saccharifying enzyme. After enzymatic hydrolysis, the enzymes are removed. Then the sediment is dried and ground to obtain porous starch. S4. The porous starch prepared in step S3 is processed according to 2-8 wt % is added to the polyvinyl alcohol / konjac glucomannan / tannic acid dispersion prepared in step S2, and stirred evenly to obtain an electrospinning solution; S5. Electrospin the electrospinning solution to obtain the nanofibers.

2. The preparation method according to claim 1, characterized in that, The polyvinyl alcohol concentration in the polyvinyl alcohol solution is 6-10%. wt %.

3. The preparation method according to claim 1, characterized in that, The konjac glucomannan solution contains 0.5-2% konjac glucomannan by mass concentration. wt %.

4. The preparation method according to claim 3, characterized in that, The amount of tannic acid added is 2-4 mg / g based on the mass of the konjac glucomannan solution.

5. The preparation method according to claim 1, characterized in that, In step S2, the heating temperature is 80-90 ℃.

6. The preparation method according to claim 1, characterized in that, The ultrasound treatment is performed for 20-40 minutes in an ultrasound machine with a power of 300-500 W and a frequency of 10-30 kHz.

7. The preparation method according to claim 1, characterized in that, Enzymatic hydrolysis involves adding 1-2% of a complex enzyme, consisting of α-amylase and saccharifying enzyme in a ratio of 1:1~3 (based on the starch mass), and performing enzymatic hydrolysis for 10-15 hours.

8. The preparation method according to claim 1, characterized in that, In step S3, after grinding, the material is sieved through an 80-120 mesh sieve.

9. Nanofibers prepared by the preparation method according to any one of claims 1-8.

10. The application of the nanofibers of claim 9 in the removal of fishy odor substances from aquatic products.

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