Polysaccharide-based nanofiber membrane capable of selective adsorption as well as preparation method and application of polysaccharide-based nanofiber membrane

Abstract

The invention discloses a selectively-adsorbable polysaccharide-based nanofiber membrane and a preparation method and application thereof, and belongs to the technical field of aquatic product processing.The preparation method of the selectively-adsorbable polysaccharide-based nanofiber membrane comprises the following steps that S1, carrageenan is dissolved in distilled water to prepare first dispersion liquid with the viscosity being 50-600 mPa.s, and the first dispersion liquid is prepared into a second dispersion liquid with the viscosity being 50-600 mPa.s; the preparation method comprises the following steps: S1, preparing first dispersion liquid with the viscosity of 200-700 mPa.s, S2, dissolving pullulan in distilled water to prepare second dispersion liquid with the viscosity of 500-1000 mPa.s, S2, mixing and stirring the first dispersion liquid and the second dispersion liquid obtained in the step S1 to obtain an electrostatic spinning solution with the viscosity of 200-700 mPa.s, and S3, pouring the obtained electrostatic spinning solution into an injector, and performing dry spinning under the room temperature condition to obtain a spinning solution. The polysaccharide-based nanofiber membrane capable of being selectively adsorbed is obtained. The polysaccharide-based nanofiber membrane capable of selective adsorption has good selective adsorption performance on flavor substances in shellfish zymolyte, and the adsorption efficiency on key fishy smell substances is remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of aquatic product processing, and in particular relates to a polysaccharide-based nanofiber membrane capable of selective adsorption, and a preparation method and application thereof. Background Art

[0002] Seafood, such as bivalve shellfish, is a delicacy consumed worldwide. It also serves as a rich source of health-promoting ingredients. Shellfish muscle tissue is rich in protein, inorganic salts, amino acids, and vitamins. High in protein and low in fat, it offers excellent nutritional and health benefits, making it a valuable marine treasure for preventing human illnesses such as chronic bronchitis, dry coughs, and phlegm. It also possesses antioxidant, anti-tumor, hepatoprotective, hypoglycemic, antibacterial, anti-cancer, and immunomodulatory properties.

[0003] In recent years, the deep processing of shellfish products has received increasing attention. Enzymatic treatment of aquatic animal protein is a key aspect of this deep processing. This method not only retains the original bioactive substances in shellfish products but also imparts new active ingredients, effectively realizing the high-value utilization of shellfish products. Shellfish hydrolysates prepared after enzymatic hydrolysis exhibit various active properties, including antioxidant, anticoagulant, antihypertensive, and anticancer properties. However, the strong fishy odor of shellfish hydrolysates has a serious impact on consumer acceptance. Therefore, the development of efficient deodorizing materials and technologies is of great significance for the processing and production of shellfish hydrolysates. Summary of the Invention

[0004] The purpose of the present invention is to provide a polysaccharide-based nanofiber membrane capable of selective adsorption and a preparation method and application thereof, so as to overcome at least one of the above-mentioned defects in the prior art.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] The present invention provides a method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane, comprising the following steps: S1: dissolving carrageenan in distilled water to prepare a first dispersion with a viscosity of 50-600 mPa·s, and dissolving pullulan in distilled water to prepare a second dispersion with a viscosity of 500-1000 mPa·s; S2: mixing the first dispersion obtained in step S1 and the second dispersion to obtain an electrospinning solution with a viscosity of 200-700 mPa·s; and S3: pouring the obtained electrospinning solution into a syringe, and performing dry spinning at room temperature to obtain a selectively adsorbable polysaccharide-based nanofiber membrane.

[0007] Preferably, between step S2 and step S3, the method further includes: dissolving the antibacterial agent in the third dispersion obtained in step S2, and stirring to obtain an electrospinning solution with a viscosity of 200-800 mPa·s.

[0008] Preferably, the volume concentration of carrageenan in the first dispersion is 0.5%-10%, the volume concentration of pullulan in the second dispersion is 10%-35%, the total volume concentration of carrageenan and pullulan in the third dispersion is 0.5%-35%, the total volume concentration of carrageenan, pullulan and antibacterial agent in the electrospinning solution is 0.8%-40%, and the volume concentration of the antibacterial agent in the electrospinning solution is 0.1%-30%.

[0009] Preferably, the carrageenan is κ-carrageenan, ι-carrageenan, λ-carrageenan, γ-carrageenan, ν-carrageenan, ξ-carrageenan or μ-carrageenan, and the antibacterial agent is at least one of citric acid, tannic acid, gallic acid, salicylic acid, azelaic acid, sorbic acid, tea polyphenols, brown algae polyphenols, anthocyanins, naringenin, and curcumin.

[0010] Preferably, the first dispersion and the second dispersion are mixed in a volume ratio of 1:0.5-8 and magnetically stirred at room temperature for 0.8-1.2 hours. The mass ratio of the antibacterial agent, carrageenan, and pullulan is 1:1-5:1-5.

[0011] Preferably, in step S4: the voltage of dry spinning is 8-25 kV, the time is 2-12 h, the diameter of the spinning needle is 0.33-1.19 mm, the solution flow rate is 0.1-5 mL / h, and the drum speed is 3-30 rpm.

[0012] The present invention also provides a selectively adsorbable polysaccharide-based nanofiber membrane, which is prepared by the above-mentioned method for preparing the selectively adsorbable polysaccharide-based nanofiber membrane.

[0013] Preferably, the fiber diameter of the selectively adsorbable polysaccharide-based nanofiber membrane is 70-87 nm, and the pore area is 17×10 5 nm 2 -27×10 5 nm 2 .

[0014] The present invention also provides an application of the selectively adsorbable polysaccharide-based nanofiber membrane in removing the fishy odor of shellfish hydrolysates.

[0015] Preferably, the shellfish hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a sealed container at a mass ratio of 1:0.1-15, and the adsorption reaction is carried out at 30-80°C for 1-24 hours to obtain the deodorized shellfish hydrolysate powder.

[0016] The beneficial effects of the present invention are:

[0017] 1. The prepared selectively adsorbable polysaccharide-based nanofiber membrane has good selective adsorption performance for flavor substances in shellfish hydrolysates, significantly improving the adsorption efficiency of key fishy substances, while effectively retaining aromatic substances.

[0018] 2. Compared with other adsorption materials (such as activated carbon, cyclodextrin, V-type starch and starch-based nanofiber membrane), the prepared selectively adsorbable polysaccharide-based nanofiber membrane has low usage, is easy to separate and recover, and has no residue.

[0019] 3. The selectively adsorbable polysaccharide-based nanofiber membrane has a three-dimensional network structure, and the pore size distribution is highly matched with the molecular size of characteristic shellfish odor substances, which can effectively capture odor substances through physical adsorption and surface interaction.

[0020] 4. Compared with traditional wet spinning, dry spinning technology eliminates the coagulation bath treatment step, shortens the process flow, and is suitable for processing a variety of polymer materials.

[0021] 5. Using distilled water as solvent and carrageenan and pullulan as raw materials, it is green, environmentally friendly, safe and non-toxic.

[0022] 6. The prepared selectively adsorbable polysaccharide-based nanofiber membrane has a fast molding speed, excellent mechanical properties, high structural uniformity, and the process parameters can be precisely controlled.

[0023] 7. The solid phase adsorption method is used to non-destructively remove the fishy odor substances in shellfish hydrolysates without contacting the original sample. The sample recovery rate can basically reach 100%, which greatly avoids the loss of nutrients. The deodorization process is simple, green, efficient, recyclable, and has a high fishy odor removal rate.

[0024] 8. Adding acids or polyphenols to the spinning solution improves the antibacterial properties of the fiber membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a scanning electron microscope image of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 1 of the present invention.

[0026] Figure 2 This is a fiber diameter distribution diagram of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 1 of the present invention.

[0027] Figure 3 This is a pore area distribution diagram of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 1 of the present invention.

[0028] Figure 4 This is a scanning electron microscope image of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 2 of the present invention.

[0029] Figure 5 This is a fiber diameter distribution diagram of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 2 of the present invention.

[0030] Figure 6 This is a pore area distribution diagram of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 2 of the present invention.

[0031] Figure 7 This is a scanning electron microscope image of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 3 of the present invention.

[0032] Figure 8 This is a fiber diameter distribution diagram of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 3 of the present invention.

[0033] Figure 9 This is a pore area distribution diagram of the selectively adsorbable polysaccharide-based nanofiber membrane prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0034] The present invention will now be further described with reference to the accompanying drawings and specific embodiments.

[0035] In the embodiment, the determination method of fishy smell removal rate and sample recovery rate is:

[0036] 1. Deodorization rate: Accurately weigh 500 mg of shellfish hydrolysate powder before and after deodorization into a 20 mL headspace bottle and quickly tighten the bottle cap. After equilibration at 30°C for 3 hours, use headspace-gas chromatography to determine the content of fishy substances in the shellfish hydrolysate powder before and after deodorization. 前 with C 后 , calculate the fishy removal rate.

[0037] Deodorization rate (%) = (before C - after C) / before C × 100%

[0038] Sample recovery rate: Determine the mass M of shellfish hydrolysate powder before and after deodorization 前 With M 后 , calculate the sample recovery rate.

[0039] Sample recovery rate (%) = M before / M after × 100%

[0040] Example 1:

[0041] like Figures 1 to 3 As shown, the method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane provided in this embodiment includes the following steps:

[0042] S1: κ-carrageenan was dissolved in distilled water at room temperature to prepare a first dispersion having a viscosity of 300 mPa·s, wherein the volume concentration of carrageenan in the first dispersion was 1.2%. Pullulan was dissolved in distilled water at room temperature to prepare a second dispersion having a viscosity of 750 mPa·s, wherein the volume concentration of pullulan in the second dispersion was 20%.

[0043] S2: The first dispersion obtained in step S1 and the second dispersion were mixed in a volume ratio of 1:4, and magnetically stirred at room temperature for 1 hour to obtain a third dispersion having a viscosity of 400 mPa·s. The total volume concentration of carrageenan and pullulan in the third dispersion was 15%.

[0044] S3: Pour the electrospinning solution obtained above into a syringe, and perform dry spinning at room temperature to obtain a polysaccharide-based nanofiber membrane that can be selectively adsorbed. Wherein: the voltage of dry spinning is 15kV, the time is 8h, the diameter of the spinning needle is 1mm, the solution flow rate is 3mL / h, and the drum speed is 15rpm. By controlling the viscosity and volume concentration at each step and combining the spinning conditions, the electrospinning solution containing carrageenan as raw material can be dry spun. The electrospinning solution containing carrageenan as traditional raw material cannot be dry spun and can only be wet spun. Compared with wet spinning, dry spinning omits the coagulation bath treatment link, greatly shortens the process flow, significantly improves production efficiency, and reduces process complexity and cost.

[0045] This embodiment also provides a selectively adsorbable polysaccharide-based nanofiber membrane, which is prepared using the above-mentioned method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane.

[0046] This embodiment also provides an application of the aforementioned selectively adsorbable polysaccharide-based nanofiber membrane in removing the fishy odor of shellfish hydrolysates.

[0047] Among them, the clam hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a closed container at a mass ratio of 1:0.5, and the clam hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are not in contact with each other. The adsorption reaction is carried out at 50°C for 12 hours to obtain the deodorized clam hydrolysate powder.

[0048] Testing revealed that clam hydrolysate powder contained hexanal, dimethyl disulfide, 2,3-butanedione, and acetone, four key odor-causing compounds. The selectively adsorbable polysaccharide-based nanofiber membrane achieved adsorption rates of 64%, 70%, 10%, and 30%, respectively. The total deodorization rate of the clam hydrolysate powder was 53%, with a sample recovery rate exceeding 99%, essentially achieving 100% recovery.

[0049] Example 2:

[0050] like Figures 4 to 6 As shown, this embodiment provides a method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane, comprising the following steps: S1: dissolving iota carrageenan in distilled water at room temperature to prepare a first dispersion having a viscosity of 300 mPa·s, wherein the volume concentration of carrageenan in the first dispersion is 1.2%. Pullulan is dissolved in distilled water at room temperature to prepare a second dispersion having a viscosity of 750 mPa·s, wherein the volume concentration of pullulan in the second dispersion is 20%.

[0051] S2: The first dispersion obtained in step S1 and the second dispersion were mixed in a volume ratio of 1:4, and magnetically stirred at room temperature for 1 hour to obtain a third dispersion having a viscosity of 400 mPa·s. The total volume concentration of carrageenan and pullulan in the third dispersion was 15%.

[0052] S3: Pour the electrospinning solution obtained above into a syringe and dry-spin at room temperature to obtain a polysaccharide-based nanofiber membrane with selective adsorption. The dry spinning voltage is 15 kV, the spinning time is 8 hours, the spinning needle diameter is 1 mm, the solution flow rate is 3 mL / h, and the drum speed is 15 rpm.

[0053] This embodiment also provides a selectively adsorbable polysaccharide-based nanofiber membrane, which is prepared using the above-mentioned method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane.

[0054] This embodiment also provides an application of the aforementioned selectively adsorbable polysaccharide-based nanofiber membrane in removing the fishy odor of shellfish hydrolysates.

[0055] Among them, the clam hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a closed container at a mass ratio of 1:0.5, and the clam hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are not in contact with each other. The adsorption reaction is carried out at 50°C for 12 hours to obtain the deodorized clam hydrolysate powder.

[0056] Testing revealed that clam hydrolysate powder contained hexanal, dimethyl disulfide, 2,3-butanedione, and acetone, four key odor-causing compounds. The selective adsorption of the polysaccharide-based nanofiber membrane resulted in adsorption rates of 78%, 80%, 36%, and 34%, respectively. The total deodorization rate of the clam hydrolysate powder was 60%, with a sample recovery rate exceeding 99%, essentially achieving 100% recovery.

[0057] Example 3:

[0058] like Figures 7 to 9As shown, this embodiment provides a method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane, comprising the following steps: S1: dissolving λ-carrageenan in distilled water at room temperature to prepare a first dispersion having a viscosity of 300 mPa·s, wherein the volume concentration of carrageenan in the first dispersion is 1.2%. Pullulan is dissolved in distilled water at room temperature to prepare a second dispersion having a viscosity of 750 mPa·s, wherein the volume concentration of pullulan in the second dispersion is 20%.

[0059] S2: The first dispersion obtained in step S1 and the second dispersion were mixed in a volume ratio of 1:4, and magnetically stirred at room temperature for 1 hour to obtain a third dispersion having a viscosity of 400 mPa·s. The total volume concentration of carrageenan and pullulan in the third dispersion was 15%.

[0060] The antimicrobial agent (tannic acid, gallic acid, and tea polyphenols) was dissolved in the third dispersion obtained in step S2 and magnetically stirred for 30 minutes to obtain an electrospinning solution with a viscosity of 500 mPa·s. The mass ratio of the antimicrobial agent, carrageenan, and pullulan was 1:3:3, the volume concentration of the antimicrobial agent in the electrospinning solution was 16%, and the total volume concentration of the carrageenan, pullulan, and antimicrobial agent in the electrospinning solution was 20%.

[0061] S3: Pour the electrospinning solution obtained above into a syringe and dry-spin at room temperature to obtain a polysaccharide-based nanofiber membrane with selective adsorption. The dry spinning voltage is 15 kV, the spinning time is 8 hours, the spinning needle diameter is 1 mm, the solution flow rate is 3 mL / h, and the drum speed is 15 rpm.

[0062] This embodiment also provides a selectively adsorbable polysaccharide-based nanofiber membrane, which is prepared using the above-mentioned method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane.

[0063] This embodiment also provides an application of the aforementioned selectively adsorbable polysaccharide-based nanofiber membrane in removing the fishy odor of shellfish hydrolysates.

[0064] Among them, the clam hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a closed container at a mass ratio of 1:0.5, and the clam hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are not in contact with each other. The adsorption reaction is carried out at 50°C for 12 hours to obtain the deodorized clam hydrolysate powder.

[0065] Testing revealed that clam hydrolysate powder contained hexanal, dimethyl disulfide, 2,3-butanedione, and acetone, four key odor-causing compounds. The selectively adsorbable polysaccharide-based nanofiber membrane achieved adsorption rates of 73%, 77%, 52%, and 60%, respectively. The total deodorization rate of the clam hydrolysate powder was 65%, with a sample recovery rate exceeding 99%, essentially achieving 100% recovery. Furthermore, the addition of acids or polyphenols to the spinning solution enhanced the antibacterial properties of the fiber membrane.

[0066] Example 4:

[0067] The difference between this embodiment and embodiment 1 is that:

[0068] The oyster hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a sealed container at a mass ratio of 1:0.5, and the oyster hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are not in contact with each other. The adsorption reaction is carried out at 50°C for 12 hours to obtain the deodorized oyster hydrolysate powder.

[0069] Testing revealed that oyster hydrolysate powder contained four key odor compounds: hexanal, octanal, benzaldehyde, and 2-methylbutanal. The selectively adsorbing polysaccharide-based nanofiber membrane achieved adsorption rates of 20%, 23%, 54%, and 26%, respectively, for these four key odor compounds. Furthermore, the selectively adsorbing polysaccharide-based nanofiber membrane also achieved adsorption rates of 20%, 58%, 7%, and 2%, respectively, for four aromatic compounds: ethyl butyrate, linalool, 2,6-dimethylpyrazine, and 2,5-dimethylfuran. The overall deodorization rate of the oyster hydrolysate powder was 41%, and the sample recovery rate was >99%, essentially achieving 100% recovery.

[0070] Example 5:

[0071] The difference between this embodiment and embodiment 1 is that:

[0072] The sea cucumber intestinal peptide powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a closed container at a mass ratio of 1:0.5, and the sea cucumber intestinal peptide powder and the selectively adsorbable polysaccharide-based nanofiber membrane are not in contact with each other. The adsorption reaction is carried out at 50°C for 12 hours to obtain the deodorized sea cucumber intestinal peptide powder.

[0073] Testing revealed that sea cucumber intestinal peptide powder contains four key odorous substances: nonanal, benzaldehyde, 1-octen-3-ol, and trimethylamine. The fiber membrane adsorbed these four key odorous substances at rates of 28%, 32%, 37%, and 29%, respectively. Sea cucumber intestinal peptide powder also contains four aromatic compounds: propyl butyrate, ethyl propionate, linalool, and 2-ethyl-6-methylpyrazine. V-type crystalline starch adsorbed these four aromatic compounds at rates of 16%, 20%, 55%, and 9%, respectively. The total deodorization rate of sea cucumber intestinal peptide powder was 43%, and the sample recovery rate was >99%, essentially achieving 100% recovery.

[0074] Comparative Example 1:

[0075] Existing technology uses starch-based nanofiber membranes to remove the fishy smell of clam hydrolysate peptide powder. The starch-based nanofiber membranes are prepared using OS starch and pullulan via electrospinning. The clam hydrolysate powder and the starch-based nanofiber membranes are placed in a sealed container at a mass ratio of 1:0.5. The mixture is then subjected to an adsorption reaction at 50°C for 12 hours to obtain the deodorized clam hydrolysate powder. The fishy smell removal rate and sample recovery of the clam hydrolysate powder were measured.

[0076] Testing revealed that clam hydrolysate powder contained hexanal, dimethyl disulfide, 2,3-butanedione, and acetone, four key odorous compounds. The fiber membrane adsorbed these four compounds at rates of 37%, 36%, 3%, and 12%, respectively. The total deodorization rate was 25%, and the sample recovery rate was 90%.

[0077] Comparative Example 2:

[0078] Existing technology uses starch-based nanofiber membranes to remove the fishy smell of oyster hydrolysate peptide powder. The starch-based nanofiber membranes are prepared using OS starch and pullulan via electrospinning. Oyster hydrolysate powder and starch-based nanofiber membranes are placed in a sealed container at a mass ratio of 1:0.5. The mixture is subjected to an adsorption reaction at 50°C for 12 hours to obtain the deodorized oyster hydrolysate powder. The deodorization rate and sample recovery rate of the oyster hydrolysate powder were measured.

[0079] Testing revealed that oyster hydrolysate powder contained four key odor compounds: hexanal, octanal, benzaldehyde, and 2-methylbutanal. The fiber membrane adsorbed these four key odor compounds at rates of 8%, 13%, 30%, and 12%, respectively. The fiber membrane also adsorbed four aromatic compounds: ethyl butyrate, linalool, 2,6-dimethylpyrazine, and 2,5-dimethylfuran. The membrane also adsorbed these four aromatic compounds at rates of 48%, 69%, 23%, and 35%, respectively. The total deodorization rate of the oyster hydrolysate powder was 34%, and the sample recovery rate was 90%.

[0080] Comparative Example 3:

[0081] S1. Preparation of V-type crystalline starch

[0082] S1.1 Slurry preparation: high amylose corn starch (Hylon-7) was prepared into a starch slurry with a dry starch mass fraction of 10% using dimethyl sulfoxide solution.

[0083] S1.2 Reaction: Heat the starch slurry from step S1.1 in a boiling water bath with continuous stirring for 2 h. Mix the hot dispersion with 3 volumes of anhydrous ethanol solution, centrifuge at 2200 g for 20 min, and discard the supernatant.

[0084] S1.3 Washing and drying: The precipitate obtained in step S1.2 was washed with anhydrous ethanol by vortexing for 6 times, centrifuged at 2200g for 20min and vacuum dried for 12h.

[0085] S1.4 Toughening: The starch powder obtained in step S1.3 was stirred and mixed with an ethanol aqueous solution (40%, v / v), heated in a 70°C water bath for 1.5 h, centrifuged at 2200 g for 20 min, and the precipitate was washed with anhydrous ethanol by vortexing 6 times, centrifuged at 2200 g for 20 min, and vacuum dried for 24 h.

[0086] S1.5 Hydration: The starch obtained in step S1.4 is placed in an environment with a relative humidity of 75% for 24 hours to obtain V-type crystalline starch.

[0087] S2. Removal of sea cucumber intestinal peptide powdery odor substances from V-type crystalline starch

[0088] Sea cucumber intestinal peptide powder and V-type crystalline starch were placed in a sealed container at a mass ratio of 1:5, and adsorption reaction was carried out at 50°C for 12 hours to obtain deodorized sea cucumber intestinal peptide powder.

[0089] Testing revealed that sea cucumber intestinal peptide powder contains four key odor compounds: nonanal, benzaldehyde, 1-octen-3-ol, and trimethylamine. V-type crystalline starch exhibited adsorption rates of 87%, 89%, 99%, and 92%, respectively, for these four key odor compounds. Sea cucumber intestinal peptide powder also contains four aromatic compounds: propyl butyrate, ethyl propionate, linalool, and 2-ethyl-6-methylpyrazine. V-type crystalline starch exhibited adsorption rates of 97%, 96%, 99%, and 99%, respectively, for these aromatic compounds. The total deodorization rate of sea cucumber intestinal peptide powder was 96%, and the sample recovery rate was 80%.

[0090] Table 1 shows the comparison of the adsorption effect of the prior art nanofiber membrane (Comparative Example 1) and the selectively adsorbable polysaccharide-based nanofiber membrane of the present invention (Examples 1-3) on key odor substances in the clam hydrolysate.

[0091] Table 1 Comparison of various indicators of adsorption effect of nanofiber membrane on key odor substances in clam enzymatic hydrolysate

[0092]

[0093] Table 2 shows the comparison of the adsorption effects of the prior art nanofiber membrane (Comparative Example 2) and the selectively adsorbable polysaccharide-based nanofiber membrane of the present invention (Example 4) on key odorous substances and aromatic substances in oyster hydrolysates.

[0094] Table 2 Comparison of the adsorption effects of nanofiber membranes on key odorous and aromatic substances in oyster hydrolysates

[0095]

[0096] The comparison of the adsorption effects of the V-type starch of the prior art (Comparative Example 3) and the selectively adsorbable polysaccharide-based nanofiber membrane of the present invention (Example 5) on key odorous substances and aromatic substances of sea cucumber intestinal peptide is shown in Table 3:

[0097] Table 3 Comparison of the adsorption effects of V-type starch and selectively adsorbable polysaccharide-based nanofiber membrane on key odorous substances and aromatic substances in sea cucumber intestinal peptide

[0098]

[0099] The fiber diameter and pore area of ​​the selectively adsorbable polysaccharide-based nanofiber membranes of Examples 1-3 are shown in Table 4:

[0100] Table 4 Fiber diameter and pore area of ​​the selectively adsorbable polysaccharide-based nanofiber membranes of Examples 1-3

[0101]

[0102] Note: Samples with different letters in a column are significantly different at p < 0.05.

[0103] As shown in the table above, in Comparative Example 1, the fishy smell removal rate and sample recovery rate of clam enzymolyte powder were low when starch-based nanofiber membrane was used to remove fishy smell. Compared with Comparative Example 1, the fishy smell removal rate and sample recovery rate of the methods of Examples 1-3 were greatly improved, and the fishy smell removal rate of clam enzymolyte powder in Example 3 was as high as 65%. The adsorption effect of nanofiber membrane on fishy substances is mostly physical adsorption, and its adsorption effect is related to its pore area and fiber diameter. A larger specific surface area and a higher porosity are conducive to the removal of fishy substances. Compared with the existing fiber membrane, the polysaccharide nanofiber membrane prepared by this method has a finer nanoscale fiber diameter size, thereby forming a dense network pore structure, presenting a larger specific surface area and a higher porosity, which is conducive to the adsorption of fishy substances by the fiber membrane.

[0104] In comparative example 2, starch-based nanofiber membrane is utilized to remove fishy smell from oyster hydrolysate powder. Compared with comparative example 2, the sample recovery rate of embodiment 4 method is greatly improved. Although the total fishy smell removal rate of sample is only improved by 7%, the polysaccharide-based nanofiber membrane of selective adsorption shows stronger adsorption capacity to the key fishy smell substances (such as benzaldehyde, 2-methylbutyraldehyde, etc.) in oyster hydrolysate, and adsorption rate is significantly improved. At the same time, the adsorption rate of aromatic compounds (such as ethyl butyrate, linalool, etc.) is significantly reduced by the method, thereby effectively removing the fishy smell substances in oyster hydrolysate, retaining its natural aromatic odor components to the greatest extent. The characteristic of this selective adsorption improves the local flavor of oyster hydrolysate, both removes bad fishy smell and retains its unique delicious aroma, providing a new technical path for the local flavor optimization of oyster hydrolysate deep-processing products.

[0105] Compared with Comparative Example 3, the sample recovery rate of the method in Example 5 is greatly improved. Although the total adsorption rate of the V-type starch used in Comparative Example 3 for sea cucumber intestinal peptides is as high as 96%, its removal rate for aromatic compounds also reaches 95%, which means that while removing the fishy substances, a large number of aromatic compounds with important flavor and nutritional value are also removed, thereby affecting the quality of the final product. In contrast, the selectively adsorbable polysaccharide-based nanofiber membrane used in Example 5 can effectively retain the aromatic compounds therein while removing the fishy substances of sea cucumber intestinal peptides, showing a higher selective adsorption capacity. In addition, the selectively adsorbable polysaccharide-based nanofiber membrane is prepared by electrospinning technology, has the characteristics of being green, environmentally friendly, non-toxic and harmless, and can be recycled, meeting the requirements of sustainable development.

[0106] In summary, the present invention uses the selectively adsorbable polysaccharide-based nanofiber membrane prepared by the preparation method to deodorize shellfish enzymatic hydrolysate powder, which can effectively remove fishy substances without contacting the original sample and retain aromatic compounds, thereby achieving the effect of not damaging the nutritional components of the original sample. This has opened up a new path for the deodorization technology of functional foods derived from aquatic products.

[0107] The present invention adopts dry spinning technology to prepare selectively adsorbable polysaccharide-based nanofiber membranes. The traditional wet spinning process needs to rely on the chemical reaction of the coagulation bath to achieve fiber solidification. The solvent and coagulation bath treatment are complicated, and during the carrageenan solution solidification process, the difference in solvent diffusion dynamics easily leads to fiber surface coarsening and internal porous structure generation, causing the fiber to produce uncontrollable structural defects. Compared with wet spinning, dry spinning eliminates the coagulation bath treatment link, significantly shortens the process flow, and is suitable for the processing of various polymer materials (such as polyethylene, carrageenan, etc.). However, the existing carrageenan dry spinning process generally adopts organic solvent systems such as dimethylformamide (DMF), dimethyl sulfoxide (DMSO), formic acid or polyvinyl pyrrolidone (PVP), which has toxicity risks. This method uses dry spinning technology for the preparation process of selectively adsorbable polysaccharide-based nanofiber membranes, using distilled water as the only solvent, which is safe and non-toxic. Using carrageenan and pullulan as raw materials is environmentally friendly, and the prepared starch nanofiber membrane has high safety and has good application prospects in the field of deodorization of edible products. The prepared fiber membrane has the advantages of fast forming speed, excellent mechanical properties, high structural uniformity, and precise control of process parameters. It is environmentally friendly and economical.

[0108] This method utilizes solid-phase adsorption to non-destructively remove odorous substances from shellfish hydrolysates without contacting the original sample, significantly reducing nutrient loss and achieving a nearly 100% sample recovery rate. Compared to existing adsorption methods using activated carbon, cyclodextrin, V-type starch, and starch-based nanofiber membranes, the selective adsorption polysaccharide-based nanofiber membrane offers advantages such as reduced usage, ease of separation and recovery, and zero residue. While achieving superior fishy deodorization, it also effectively minimizes nutrient loss during the deodorization process.

[0109] The present invention uses dry spinning technology to produce a selectively adsorbable polysaccharide-based nanofiber membrane. Compared to the fiber micelles produced by traditional wet spinning methods, the nanofiber membrane has a three-dimensional network structure that can be used to adsorb various flavor compounds. Scanning electron microscopy revealed that the resulting selectively adsorbable polysaccharide-based nanofiber membrane has a porous network structure with a diameter of 70-87 nm and a pore area of ​​17×10 5 nm 2 -27×10 5 nm 2 , whose pore size distribution closely matches the molecular size of characteristic shellfish odor substances. This size selectivity enables the fiber membrane to effectively capture odor substances through physical adsorption and surface interactions. In contrast, although starch-based nanofiber membranes also have certain adsorption capacity, their fiber diameter and pore size distribution are poor, resulting in significantly reduced adsorption efficiency.

[0110] The present invention provides a novel selectively adsorbable polysaccharide-based nanofiber membrane material that exhibits excellent selective adsorption properties for flavor substances in shellfish hydrolysates. Compared to existing starch-based nanofiber membranes, the selectively adsorbable polysaccharide-based nanofiber membrane of the present invention increases the total adsorption rate of shellfish hydrolysates from 19% to 65%, significantly improves the adsorption efficiency of key fishy odor substances such as hexanal, octanal, 1-octen-3-ol, and dimethyl disulfide, and increases the retention of aromatic substances such as ethyl butyrate, linalool, 2,6-dimethylpyrazine, and 2,5-dimethylfuran. Compared to V-type crystalline starch, the selectively adsorbable polysaccharide-based nanofiber membrane of the present invention exhibits excellent selective adsorption properties. While effectively removing key fishy odor substances from shellfish hydrolysates, the material can maximize the retention of aromatic substances in the shellfish hydrolysates, thereby achieving the goal of removing unpleasant flavors while maintaining the original aromatic characteristics of the shellfish hydrolysates.

[0111] The present invention provides a method for removing powdery and fishy substances from shellfish enzymatic hydrolysates by utilizing a selectively adsorbable polysaccharide-based nanofiber membrane, which is simple to operate, green, efficient, recyclable, does not directly contact the sample, and does not damage the nutrients.

[0112] The present invention mixes carrageenan with a pullulan solution and prepares a starch-based nanofiber membrane through electrospinning technology. The fiber membrane has a large specific surface area and a loose and porous three-dimensional network structure, and has good selective adsorption capacity for fishy substances, thereby achieving the purpose of removing the fishy smell of shellfish hydrolysates. At the same time, adding acids or polyphenols to the spinning solution improves the antibacterial properties of the fiber membrane. The present invention uses a selectively adsorbable polysaccharide-based nanofiber membrane as an adsorption material to remove the fishy smell of shellfish hydrolysates. The process is simple, green, efficient, and recyclable. It can effectively remove fishy substances without contacting the original sample, achieving the effect of not damaging the nutritional components of the original sample.

[0113] In general, the selectively adsorbable polysaccharide-based nanofiber membrane used in the present invention absorbs fishy odor components. The raw materials are green and safe, the preparation process is simple and fast, the fiber membrane is recyclable, and the original nutrients of shellfish hydrolysates can be retained. The fishy odor removal rate is high, opening up a new path for the deodorization technology of functional foods derived from aquatic products.

[0114] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane, characterized in that: The following steps are involved: S1: dissolving carrageenan in distilled water to prepare a first dispersion having a viscosity of 50-600 mPa·s, and dissolving pullulan in distilled water to prepare a second dispersion having a viscosity of 500-1000 mPa·s; S2: mixing the first dispersion obtained in step S1 and the second dispersion to obtain an electrospinning solution with a viscosity of 200-700 mPa·s; S3: The obtained electrospinning solution is poured into a syringe and dry-spinned at room temperature to obtain a polysaccharide-based nanofiber membrane with selective adsorption.

2. The method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane according to claim 1, characterized in that: The following steps are included between step S2 and step S3: The antibacterial agent is dissolved in the third dispersion obtained in step S2, and stirred to obtain an electrospinning solution with a viscosity of 200-800 mPa·s.

3. The method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane according to claim 2, wherein: The volume concentration of carrageenan in the first dispersion is 0.5%-10%; The volume concentration of pullulan in the second dispersion is 10%-35%; The total volume concentration of carrageenan and pullulan in the third dispersion is 0.5%-35%; The total volume concentration of carrageenan, pullulan and antimicrobial agent in the electrospinning solution ranged from 0.8% to 40%; The volume concentration of the antibacterial agent in the electrospinning solution is 0.1%-30%.

4. The method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane according to claim 2, wherein: Carrageenan is κ-carrageenan, ι-carrageenan, λ-carrageenan, γ-carrageenan, ν-carrageenan, ξ-carrageenan or μ-carrageenan; The antibacterial agent is at least one of citric acid, tannic acid, gallic acid, salicylic acid, azelaic acid, sorbic acid, tea polyphenols, brown algae polyphenols, anthocyanidins, naringenin, and curcumin.

5. The method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane according to claim 2, wherein: The first dispersion and the second dispersion were mixed in a volume ratio of 1:0.5-8 and magnetically stirred at room temperature for 0.8-1.2 h; The mass ratio of the antibacterial agent, carrageenan and pullulan is 1:1-5:1-5.

6. The method for preparing a selectively adsorbable polysaccharide-based nanofiber membrane according to claim 1, characterized in that: In step S4: The voltage of dry spinning is 8-25 kV, the time is 2-12 h, the diameter of the spinning needle is 0.33-1.19 mm, the solution flow rate is 0.1-5 mL / h, and the drum speed is 3-30 rpm.

7. A polysaccharide-based nanofiber membrane capable of selective adsorption, characterized by: The selectively adsorbable polysaccharide-based nanofiber membrane is prepared by the method for preparing the selectively adsorbable polysaccharide-based nanofiber membrane according to any one of claims 1 to 6.

8. The selectively adsorbable polysaccharide-based nanofiber membrane according to claim 7, characterized in that: The fiber diameter of the selectively adsorbable polysaccharide-based nanofiber membrane is 70-87 nm, and the pore area is 17×10 5 nm 2 -27×10 5 nm 2 .

9. Use of the selectively adsorbable polysaccharide-based nanofiber membrane according to any one of claims 7 to 8 in removing the fishy odor of shellfish hydrolysates.

10. The use according to claim 9, characterized in that: The shellfish hydrolysate powder and the selectively adsorbable polysaccharide-based nanofiber membrane are placed in a sealed container at a mass ratio of 1:0.1-15, and the adsorption reaction is carried out at 30-80° C. for 1-24 hours to obtain the deodorized shellfish hydrolysate powder.

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