Edible composite membrane of water-soluble dietary fiber and collagen as well as preparation and application of edible composite membrane
By preparing konjac oligosaccharides through microbial hydrolysis of konjac glucomannan and combining them with collagen to form an edible composite film, the problems of insufficient mechanical properties, thermal stability and antibacterial activity of collagen films were solved, and significant performance improvement was achieved.
Patent Information
- Application Number
- CN202411868597.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2026-02-03
AI Technical Summary
Collagen membranes have problems such as weak mechanical properties, poor thermal stability, poor antibacterial activity, and poor preservation performance.
Konjac oligosaccharides prepared by microbial hydrolysis of konjac glucomannan are used as excipients and combined with collagen to form an edible composite film of water-soluble dietary fiber and collagen. The mechanical properties, thermal stability and antibacterial activity are improved through cross-linking.
The mechanical strength, thermal stability, and antibacterial activity of edible composite films were significantly improved, with tensile strength increasing by 167.6%-241.6%, thermal stability by 127.5%-156.8%, antibacterial rate by 227.5%-521.9%, water vapor barrier performance by 113.6%-140.3%, moisture resistance by 104.7%-121.3%, and swelling performance by 103.3%-258.2%.
Smart Images
Figure CN121449933A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of biomaterials technology, and more specifically, relates to an edible composite membrane of water-soluble dietary fiber and collagen, and its preparation and application. Background Technology
[0002] Collagen is a functional protein found in animal skin, tendons, and connective tissue, and can be processed into edible films. Edible collagen films, with their significant advantages such as stable supply, controllable mechanized production processes, and high consistency with the shrinkage properties of minced meat, are currently the most widely used meat product packaging material, commonly used in sausage casings. However, they suffer from drawbacks such as low mechanical strength and poor thermal stability. Current research both domestically and internationally indicates that preparing composite films by combining animal and plant proteins, polysaccharides, and macromolecules such as cellulose and its derivatives can effectively improve the basic properties of collagen films.
[0003] Dietary fiber is an edible part of a plant or a carbohydrate analogue that is not digested and absorbed in the small intestine but can be fully or partially fermented in the large intestine. It has health benefits such as lowering blood sugar and lipids and preventing cancer, and has been widely used as a functional food additive in recent years.
[0004] Konjac glucomannan is a high-quality natural soluble dietary fiber and a major component of the tuber of the perennial herbaceous plant konjac. Konjac glucomannan possesses excellent physicochemical properties, including good film-forming, rheological, hydrophilic, and gelling properties, as well as pharmacological activities such as promoting bowel movements, lowering blood sugar and lipids, and preventing cancer, making it an excellent natural biomaterial. Konjac oligosaccharides obtained through microbial hydrolysis can address the high viscosity of konjac glucomannan while retaining or even enhancing its original physiological functions. When added to collagen, they can cross-link, improving the basic properties of collagen membranes and imparting certain health benefits to edible films. In conclusion, to adapt to the increasing number of sub-healthy individuals, this study provides a theoretical basis for the preparation and application of soluble dietary fiber / collagen edible films. Summary of the Invention
[0005] To address the technical problems of poor mechanical properties, poor thermal stability, poor antibacterial activity, and poor preservation performance of collagen films, this invention provides an edible composite film of water-soluble dietary fiber KOGM and collagen COL and its preparation method. Using a layered collagen network as the matrix and adding microbially hydrolyzed konjac oligosaccharides as an auxiliary material, an edible composite film with strong mechanical properties, strong thermal stability, high antibacterial activity, and good preservation performance is prepared.
[0006] According to a first aspect of the present invention, a method for preparing an edible composite film of water-soluble dietary fiber and collagen is provided, comprising the following steps:
[0007] (1) Prepare a culture medium by mixing konjac glucomannan with a nitrogen source and sterilize it;
[0008] (2) Add the edible and medicinal fungus Ganoderma lucidum to the culture medium obtained in step (1) for culture and fermentation, and then centrifuge to remove the precipitate to obtain hydrolyzed konjac oligosaccharide;
[0009] (3) After swelling the collagen, add the konjac oligosaccharide obtained in step (2) to obtain a film-forming solution;
[0010] (4) Pour the film-forming liquid obtained in step (3) into a mold and dry it to obtain an edible composite film of water-soluble dietary fiber and collagen.
[0011] Preferably, the collagen is extracted from animal tendons or connective tissue, or the collagen is extracted from animal skin.
[0012] Preferably, the collagen is derived from animal tendons or connective tissues, and collagen extracted from skin can be of animal origin such as cattle, pigs, horses, sheep, or fish.
[0013] Preferably, the water-soluble dietary fiber is a polysaccharide derived from edible and medicinal herbaceous or woody plants, and more preferably, konjac.
[0014] Preferably, the mass ratio of collagen to konjac oligosaccharide is (1.25-8):1.
[0015] Preferably, step (3) further includes adding glycerol to the film-forming solution;
[0016] Preferably, in step (3), the amount of glycerol added is 10%-20% of the sum of the mass of collagen and konjac oligosaccharide.
[0017] Preferably, the concentration of konjac glucomannan in the culture medium is 0.4 g / mL to 1.0 g / mL.
[0018] Preferably, the fungus Ganoderma is Ganoderma lucidum of the Ganodermataceae family.
[0019] According to another aspect of the present invention, an edible composite membrane of water-soluble dietary fiber and collagen is provided.
[0020] Preferably, it comprises 10%-40% konjac oligosaccharides, 50%-80% collagen, and 10%-20% glycerol by weight.
[0021] Preferably, the edible composite film is in the form of a sheet film, casing, or tubular film.
[0022] According to another aspect of the present invention, the application of the aforementioned edible composite film of water-soluble dietary fiber and collagen as a meat packaging film is provided.
[0023] Preferably, the meat packaging film is a sausage casing. Overall, compared with the prior art, the above technical solution conceived by this invention mainly possesses the following technical advantages:
[0024] (1) The raw materials of this invention are collagen and konjac glutanol (KGM), both of which are biorenewable resources. KOGM, a soluble dietary fiber in functional foods, can be used as an excipient to improve the basic properties of edible collagen films and impart additional health benefits, thus providing a theoretical basis for the preparation and application of edible soluble dietary fiber / collagen films. Furthermore, it has low environmental impact, low cost, and strong film-forming properties. The food films synthesized from it have application prospects comparable to films prepared from fossil-based polymers and can occupy a place in the market.
[0025] (2) In this invention, KOGM is obtained by microbial fermentation and hydrolysis of konjac glucomannan (KGM) to different degrees of hydrolysis. In this process, KGM retains its good film-forming properties, hydrophilicity and rheological properties, while improving the high viscosity of KGM. KOGM prepared from KGM can improve the high viscosity of KGM and has excellent water solubility, stable storage, good heat resistance, effective antibacterial properties and excellent acid resistance, as well as high biological activity. It has great potential as an excipient for edible collagen films. The edible composite film of the present invention has the following advantages: high mechanical strength, with its tensile strength increased by 167.6%-241.6% compared with pure collagen film; good thermal stability, with the maximum thermal weight loss rate reduced by 127.5%-156.8% compared with pure collagen film; high antibacterial activity, with its antibacterial rate increased by 227.5%-521.9% compared with pure collagen film; and improved water vapor barrier performance by 113.6%-140.3%, moisture-proof performance by 104.7%-121.3%, swelling performance by 103.3%-258.2%, and uniform surface. Attached Figure Description
[0026] Figure 1 This is a production process flow diagram of the present invention.
[0027] Figure 2 This is a graph showing the changes in total sugar and reducing sugar in KGM hydrolyzed by microbial fermentation according to the present invention.
[0028] Figure 3 These are SEM micrographs of the surface and cross-section of the KOGM / COL edible composite film prepared according to the present invention.
[0029] Figure 4These are thermogravimetric analysis (TGA) charts of different KOGM / COL edible composite films according to the present invention.
[0030] Figure 5 These are test diagrams of the antibacterial properties of different KOGM / COL edible composite films according to the present invention.
[0031] Figure 6 These are test diagrams of the mechanical strength of different KOGM / COL edible composite films according to the present invention.
[0032] Figure 7 This is a test chart of the swelling ratio of different KOGM / COL edible composite films according to the present invention. Detailed Implementation
[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.
[0034] This invention provides a method for preparing an edible composite membrane of soluble dietary fiber KOGM / collagen COL, comprising the following steps:
[0035] (1) Prepare culture media by mixing different concentrations of konjac glucomannan (KGM) with an appropriate amount of nitrogen source, and then sterilize them;
[0036] (2) Add the edible and medicinal fungus Ganoderma lucidum to the culture medium obtained in step (1) for culture and fermentation, and then centrifuge to remove the precipitate to obtain konjac oligosaccharides KOGM with different degrees of hydrolysis.
[0037] (3) After swelling the collagen, add the KOGM obtained in step (2) and stir thoroughly to obtain an edible film-forming solution.
[0038] (4) Pour the mixed solution obtained in step (3) into a mold and dry it to obtain a soluble dietary fiber / collagen edible composite film.
[0039] Preferably, in step (1), the nitrogen source is ammonium nitrate.
[0040] Preferably, in step (2), the edible and medicinal fungus is from the Ganodermacetes family.
[0041] Preferably, in step (2), the culture time is 3 to 5 days.
[0042] Preferably, in step (3), the mass ratio of collagen to konjac oligosaccharide is (1.25-8):1.
[0043] Preferably, step (3) includes adding glycerol to the film-forming solution.
[0044] Preferably, in step (3), the amount of glycerol added is 10%-20% of the sum of the mass of collagen, konjac oligosaccharide and glycerol.
[0045] In some embodiments, the collagen swelling conditions in step (3) are: standing at 4°C for 12-24 hours, followed by stirring for 12-24 hours.
[0046] According to another aspect of the present invention, a soluble dietary fiber / collagen edible composite membrane prepared by any one of the methods described herein is provided.
[0047] According to another aspect of the present invention, the edible composite film of soluble dietary fiber / collagen is provided for use as a meat packaging film.
[0048] In this invention, konjac glucomannan (KGM) often negatively impacts product quality due to its high viscosity. After microbial fermentation and hydrolysis, the β-glucomanase produced by fungi during deep liquid fermentation can randomly cleave KGM, yielding konjac oligosaccharides (KOGM) of different molecular weights more suitable as excipients for edible collagen films. Simultaneously, the active ingredients produced by the edible and medicinal fungus Ganoderma lucidum during fermentation also enhance the health benefits of the edible film. Based on the changes in total sugar and reducing sugar content in different KGM culture media, the final reducing sugar concentrations in each KGM culture medium reached 1.16, 3.50, 4.07, and 5.04 times the initial values, respectively, indicating the hydrolytic effect of fungi on KGM.
[0049] Figure 1 This is a flow chart of the production process of the present invention. The present invention provides a method for preparing an edible composite membrane of soluble dietary fiber KOGM / collagen COL, the method comprising the following specific steps:
[0050] (1) Weigh an appropriate amount of konjac flour, dissolve it in an appropriate amount of distilled water, then add 3g of ammonium nitrate as a nitrogen source, continue to add distilled water to 100mL, and finally sterilize at 115℃ for 30min.
[0051] (2) At 28℃, the edible and medicinal fungus Ganoderma lucidum was cultured and fermented in the above four culture media for 5 days. After that, the precipitate was removed by centrifugation to obtain KOGM solutions with different degrees of hydrolysis.
[0052] (3) Collagen was swollen by adding an appropriate amount of ultrapure water at low temperature to obtain a collagen swelling solution;
[0053] (4) Mix the KOGM solution in step (2) with the collagen swelling solution in step (3) and stir evenly. Preferably, add glycerin and continue to mix and stir evenly to obtain a film-forming solution.
[0054] (5) Pour the film-forming liquid stirred in step (4) into a mold and dry it in a 37°C drying oven for 2-3 days to obtain a soluble dietary fiber KOGM / collagen edible composite film.
[0055] The soluble dietary fiber KOGM / collagen edible composite membrane prepared by this invention comprises 10%-40% KOGM, 50%-80% collagen, and 10%-20% glycerol by weight.
[0056] The following are specific embodiments.
[0057] Example 1
[0058] Dissolve 0.4g, 0.6g, 0.8g, and 1.0g of konjac flour in appropriate amounts of ultrapure water, respectively, and stir thoroughly until no obvious lumps form. Add 0.3g of ammonium nitrate as a nitrogen source to each culture medium, and continue to add ultrapure water to 100mL. Sterilize at 115℃ for 30min to obtain four KGM concentrations of 0.4%, 0.6%, 0.8%, and 1.0%. Inoculate the Ganoderma lucidum EN2 strain into the above culture media, and culture in a constant temperature shaker for 5 days. Measure the changes in reducing sugar and total sugar during the period. Figure 2 The results showed a significant increase in reducing sugar content starting from the third day. After 5 days of culture, the bacterial culture was centrifuged to remove the precipitate, yielding the supernatant KOGM solution: the solid contents were as follows: KOGM1 solution: 6.7 mg / mL; KOGM2 solution: 7.0 mg / mL; KOGM3 solution: 8.7 mg / mL; KOGM4 solution: 10.7 mg / mL.
[0059] Weigh out 40g (6mg / mL) of collagen swelling solution and stir at 4℃ for 2h. Then add different volumes of KOGM1-4 solution with the same solid content, namely 6.0mL of KOGM1 solution, 5.7mL of KOGM2 solution, 4.6mL of KOGM3 solution and 3.8mL of KOGM4 solution. Continue stirring at 4℃ for 12h. Then add glycerol with a solid content of 15.15% and stir at 4℃ for 10min to obtain the film-forming solution.
[0060] After sonicating the film-forming solution for 2 minutes, let it stand for 2 hours to remove air bubbles. Then pour it into a mold and dry it in a 37℃ constant temperature drying oven for 48 hours to finally obtain a KOGM / COL edible composite film with high tensile strength and high antibacterial properties.
[0061] In Example 1, the KOGM1-4 / COL edible composite film was composed of 12.4% KOGM1-KOGM4, 74.44% collagen, and 13.16% glycerol by weight.
[0062] Example 2
[0063] Dissolve 0.4g, 0.6g, 0.8g, and 1.0g of konjac flour in appropriate amounts of ultrapure water, stirring thoroughly until no obvious lumps form. Add 0.3g of ammonium nitrate as a nitrogen source to each solution, and continue adding ultrapure water to 100mL. Sterilize at 115℃ for 30min to obtain four KGM concentrations of 0.4%, 0.6%, 0.8%, and 1.0%. Inoculate the above culture media with the Ganoderma lucidum EN2 strain (Ganodermaceae), and culture on a shaker at a constant temperature for 5 days. Centrifuge to remove the precipitate, obtaining the supernatant KGM solutions with the following solid contents: KOGM1: 6.7mg / mL; KOGM2: 7.0mg / mL; KOGM3: 8.7mg / mL; KOGM4: 10.7mg / mL.
[0064] Weigh out 30g (6mg / mL) of collagen swelling solution and stir at 4℃ for 2h. Then add different volumes of KOGM1-4 solution with the same solid content, namely 9.0mL of KOGM1 solution, 8.6mL of KOGM2 solution, 6.9mL of KOGM3 solution and 5.6mL of KOGM4 solution. Continue stirring at 4℃ for 12h. Then add glycerol with a solid content of 18.52% and stir at 4℃ for 10min to obtain the film-forming solution.
[0065] After sonicating the film-forming solution for 2 minutes, let it stand for 2 hours to remove air bubbles. Then pour it into a mold and dry it in a 37℃ constant temperature drying oven for 48 hours to finally obtain a KOGM / COL edible composite film with high tensile strength and high antibacterial properties.
[0066] In Example 2, the KOGM1-KOGM4 / COL edible composite film was composed of 21.09% KOGM1-KOGM4, 63.28% collagen, and 15.63% glycerol by weight. The surface and cross-section of the prepared edible composite film were analyzed using environmental scanning electron microscopy, and the results are shown below. Figure 3 After adding KOGM, the surface of the edible film became smoother and more uniform. Cross-sectional analysis showed that the addition of KOGM did not disrupt the layered network structure of collagen, indicating that KOGM was uniformly distributed within the collagen fiber network. Furthermore, the thermal stability, antibacterial properties, mechanical properties, and swelling properties of the edible composite film were characterized and analyzed, with results as follows: Figure 4 , 5 As shown in Figures 6 and 7. Figure 4The study showed that the maximum thermal degradation rate of edible films with added KOGM was significantly lower than that of collagen films, decreasing by 156.8%, indicating that the cross-linking effect improved the thermal stability of the edible films. Figure 5 The inhibition rates of various membranes against *E. coli* showed that the addition of KOGM had a significant inhibitory effect on *E. coli*, increasing the inhibition rate by 21.9%. This may be because the extracellular active substances secreted by EN2 include flavonoids and triterpenoids, which have certain bactericidal effects. Finally... Figure 6 The tensile strength and elongation at break of each membrane were shown. Compared to the pure collagen membrane, the edible membrane with added KOGM exhibited higher tensile strength, with a 241.6% increase, indicating a corresponding improvement in the rigidity of the edible membrane. Finally, Figure 7 The swelling ratios of each membrane were shown. KOGM retains the hydrophilic and water-holding properties of KGM, exhibiting a high swelling ratio, increased by 258.2%, which may provide some weight-loss benefits. In summary, KOGM contains abundant hydroxyl groups that can form hydrogen bonds with collagen, improving the thermal stability and mechanical properties of edible films, and endowing them with strong antibacterial and swelling properties.
[0067] Example 3
[0068] Dissolve 0.4g, 0.6g, 0.8g, and 1.0g of konjac flour in appropriate amounts of ultrapure water, stirring thoroughly until no obvious lumps form. Add 0.3g of ammonium nitrate as a nitrogen source to each solution, and continue adding ultrapure water to 100mL. Sterilize at 115℃ for 30min to obtain four KGM concentrations of 0.4%, 0.6%, 0.8%, and 1.0%. Inoculate the above culture media with the Ganoderma lucidum EN2 strain (Ganodermaceae), and culture on a shaker at a constant temperature for 5 days. Centrifuge to remove the precipitate, obtaining the supernatant KGM solutions with the following solid contents: KOGM1: 6.7mg / mL; KOGM2: 7.0mg / mL; KOGM3: 8.7mg / mL; KOGM4: 10.7mg / mL.
[0069] Weigh out 35g (6mg / mL) of collagen swelling solution and stir at 4℃ for 2h. Then add different volumes of KOGM1-4 solution with the same solid content, namely 12.0mL of KOGM1 solution, 11.4mL of KOGM2 solution, 9.2mL of KOGM3 solution and 7.5mL of KOGM4 solution. Continue stirring at 4℃ for 12h. Then add glycerol with a solid content of 18.52% and stir at 4℃ for 10min to obtain the film-forming solution.
[0070] The film-forming solution was sonicated for 2 minutes and then allowed to stand for 2 hours to remove air bubbles. It was then poured into a mold and dried in a 37°C constant temperature drying oven for 48 hours to finally obtain a KOGM / COL edible composite film with high tensile strength and high antibacterial properties.
[0071] In Example 3, the KOGM1-4 / COL edible composite film was composed of 23.28% KOGM1-4, 61.09% collagen and 15.63% glycerol by weight.
[0072] This study used the edible and medicinal fungus Ganoderma lucidum to directly bio-hydrolyze KJO-GM, and analyzed the sugar content during the hydrolysis process. The hydrolyzed konjac oligosaccharide (KOGM) was used as an excipient in edible collagen films to prepare a konjac oligosaccharide / collagen edible composite film. The edible film had a smoother and more uniform surface and a layered network structure. Furthermore, its thermal stability, mechanical properties, antibacterial properties, and swelling properties were significantly improved. This invention not only improves the basic properties of pure collagen edible films but also endows them with certain health benefits, providing a theoretical basis for the preparation and application of soluble dietary fiber / collagen edible films.
[0073] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing an edible composite film of water-soluble dietary fiber and collagen, characterized in that, Includes the following steps: (1) Prepare a culture medium by mixing konjac glucomannan with a nitrogen source and sterilize it; (2) Add the edible and medicinal fungus Ganoderma lucidum to the culture medium obtained in step (1) for culture and fermentation, and then centrifuge to remove the precipitate to obtain hydrolyzed konjac oligosaccharide; (3) After swelling the collagen, add the konjac oligosaccharide obtained in step (2) to obtain a film-forming solution; (4) Pour the film-forming liquid obtained in step (3) into a mold and dry it to obtain an edible composite film of water-soluble dietary fiber and collagen.
2. The method for preparing the edible composite film of water-soluble dietary fiber and collagen as described in claim 1, characterized in that, The collagen is extracted from animal tendons or connective tissue, or from animal skin.
3. The method for preparing the edible composite film of water-soluble dietary fiber and collagen as described in claim 1, characterized in that, The mass ratio of collagen to konjac oligosaccharide is (1.25-8):
1.
4. The method for preparing the edible composite film of water-soluble dietary fiber and collagen as described in claim 1, characterized in that, Step (3) also includes adding glycerol to the film-forming solution; Preferably, in step (3), the amount of glycerol added is 10%-20% of the sum of the mass of collagen and konjac oligosaccharide.
5. The method for preparing the edible composite film of water-soluble dietary fiber and collagen as described in claim 1, characterized in that, The concentration of konjac glucomannan in the culture medium was 0.4 g / mL to 1.0 g / mL.
6. The method for preparing the edible composite film of water-soluble dietary fiber and collagen as described in claim 1, characterized in that, The fungus mentioned is Ganoderma Lucidum, belonging to the Ganodermataceae family.
7. An edible composite membrane of water-soluble dietary fiber and collagen prepared by any one of claims 1-6.
8. The edible composite membrane of water-soluble dietary fiber and collagen as described in claim 7, characterized in that, It includes 10%-40% konjac oligosaccharides, 50%-80% collagen, and 10%-20% glycerol by weight.
9. The edible composite membrane of water-soluble dietary fiber and collagen as described in claim 7, characterized in that, The edible composite film is in the form of sheet film, casing or tubular film.
10. The application of the edible composite film of water-soluble dietary fiber and collagen as described in claim 9 or 10 as a meat packaging film; Preferably, the meat packaging film is a sausage casing.