Konjak gel food as well as preparation method and application thereof

Abstract

The invention relates to the field of konjak food, provides konjak gel food as well as a preparation method and application thereof, and aims to solve the problems of poor stability, insufficient brittleness and poor antibacterial property of existing konjak gel food. According to the gel food, phosphorylated konjac glucomannan serves as a main body, chitosan / microcrystalline cellulose composite filler, carrageenan, sodium alginate, calcium salt, citrate and other auxiliary materials are added, a multi-cross-linked network structure is constructed through the synergistic effect of multiple components, and the stability and mechanical performance of gel are remarkably enhanced. In the preparation process, a temperature gradient control strategy is adopted, and ordered construction and layer-by-layer curing of a gel network are achieved. The obtained product has high gel strength, excellent brittleness, low bleeding rate and excellent antibacterial performance, can be widely applied to functional food simulating the mouth feel of animal cartilage, and has good storage stability and sensory quality.

Description

Technical Field

[0001] The invention relates to the field of konjac food materials, and in particular to a konjac gel food and a preparation method and application thereof. Background Art

[0002] With the growing demand for healthy diets, functional foods, and plant-based alternatives, gel foods with unique taste and nutritional value are gradually becoming an important part of the food industry. Especially in the development of functional foods that simulate the taste of animal cartilage tissue, konjac gel has attracted widespread attention due to its natural, low-calorie, and good gelling properties. In such applications, the gel material must not only have a good chewing feel, but also be close to real cartilage tissue in terms of structural strength and sensory level, so as to meet consumers' dual needs for taste simulation and eating experience. Specifically, konjac gel foods need to have high structural stability to ensure that they do not deform or lose water during storage and processing; at the same time, they should have moderate brittleness to simulate the feeling of cartilage breaking during chewing; in addition, for food safety and preservation needs, the gel should also have good antibacterial properties to extend the shelf life and reduce the risk of microbial contamination. The improvement of the above performance requirements will not only help enhance the market competitiveness of the products, but also expand the application boundaries of konjac gel in many emerging fields such as plant-based foods, special nutritional foods and functional foods. Therefore, systematic material design and process optimization around the structural regulation and functional enhancement of konjac gel have become a key path to promote the high-quality development of this type of food.

[0003] At present, although there are a variety of konjac-based gel food products and related technical solutions on the market, there are still certain limitations in meeting the needs of high-performance applications, especially in terms of stability, brittleness and antibacterial properties. For example, Chinese patent publication number CN114903159A discloses a production process for fresh bamboo shoots and konjac instant food, which uses a rinsing and dehydration device to achieve efficient coordinated processing of bamboo shoots and konjac. The process has the advantages of simple operation, nutritional health, flavor retention and suitability for large-scale production. However, after long-term storage or in complex environments, the gel structure is still prone to loosening and water precipitation, reflecting that its stability improvement is limited; for example, patent publication number CN109699974A discloses a konjac formula food, which proposes to adjust the mouthfeel of konjac gel by using plasticizers such as flour and kudzu powder to enhance flexibility. However, this method often sacrifices brittleness and is difficult to restore the real feeling of cartilage tissue fracture; in addition, some patents attempt to achieve antibacterial function by adding natural plant extracts, but their antibacterial activity is limited by the distribution of ingredients and interfacial binding force, resulting in unstable and non-lasting actual antibacterial effect. Overall, the existing technology has not yet achieved an effective breakthrough in material structure design and functional synergistic enhancement, and it is difficult to simultaneously meet the comprehensive requirements of high stability, high brittleness and excellent antibacterial properties. Therefore, it is urgent to systematically optimize the konjac gel system through new material modification methods and composite strategies to achieve its wide application in high-end functional foods. Summary of the Invention

[0004] (1) Technical problems solved The invention aims to provide a konjac gel food and a preparation method and application thereof, so as to solve the problems of poor stability, insufficient brittleness and insufficient antibacterial performance of the current konjac gel food.

[0005] (2) Technical solution In order to achieve the above object, the present invention provides the following technical solutions: A konjac gel food comprises the following raw materials in parts by weight: 50.0-100.0 parts of phosphorylated konjac glucomannan, 25.0-40.0 parts of chitosan / microcrystalline cellulose composite filler, 2.0-6.0 parts of calcium chloride, 1.0-4.0 parts of trisodium citrate, 1.0-5.0 parts of citric acid, 1.0-3.0 parts of sodium trimetaphosphate, 2.0-8.0 parts of carrageenan, 2.0-6.0 parts of sodium alginate, 1.0-3.0 parts of calcium lactate, and 200.0-400.0 parts of deionized water; The phosphorylated konjac glucomannan is obtained by reacting konjac glucomannan with phosphate, drying, and pulverizing; The chitosan / microcrystalline cellulose composite filler consists of microcrystalline cellulose and chitosan particles loaded on the surface of the microcrystalline cellulose, and achieves a synergistic effect of enhanced stability and improved brittleness through a multiple cross-linked network structure.

[0006] Furthermore, the mass ratio of microcrystalline cellulose to chitosan in the chitosan / microcrystalline cellulose composite filler is (1.0-5.0): (0.5-2.0); The chitosan / microcrystalline cellulose composite filler has an average particle length of 16-50 μm and an average diameter of 2.0-5.0 μm.

[0007] Furthermore, the mass ratio of the phosphorylated konjac glucomannan to the chitosan / microcrystalline cellulose composite filler is (1-4): (0.5-2); The weight ratio of the carrageenan to sodium alginate is (1-3): (1-2); The weight ratio of the calcium chloride to calcium lactate is (1-3): (0.5-1.5).

[0008] Furthermore, the phosphate is sodium tripolyphosphate and sodium trimetaphosphate; The phosphorylation degree of the phosphorylated konjac glucomannan is 0.04-0.20; the intermolecular hydrogen bonding and ionic cross-linking effects are enhanced by the introduction of phosphate groups.

[0009] The present invention adopts the design of phosphorylated konjac glucomannan and chitosan / microcrystalline cellulose composite filler collaborative construction, and is mainly used for strengthening the structural stability, brittle performance and antimicrobial properties of konjac gel food. Phosphate group is introduced by phosphate, so that konjac glucomannan is possessed with good hydrogen bond forming ability and ionic crosslinking ability, and stable electrostatic interaction occurs between the chitosan protonated amino group. Simultaneously, phosphate group can also form hydrogen bond with microcrystalline cellulose hydroxyl, and constructs the multi-level cross-linked network structure jointly composed of intramolecular hydrogen bond, electrostatic crosslinking and calcium ion bridging. Microcrystalline cellulose provides rigid support skeleton in the system, and chitosan then acts as flexible connecting unit, and the two realize the steric stability of network structure and the synergistic enhancement of mechanical property together. Citric acid and its sodium salt are adjusted system pH, further optimize the protonation state of chitosan, and regulate charge distribution and crosslinking strength. On this basis, the cationic properties of chitosan impart excellent antimicrobial properties to the gel. Its protonated amino groups can bind to bacterial cell walls through electrostatic interactions, disrupting their membrane structure and inhibiting their growth and reproduction. The granular distribution enhances the contact efficiency between the antimicrobial components and microorganisms, ensuring that the gel possesses sustained and stable antimicrobial properties even under room temperature storage conditions. This synergistic system not only builds a stable network but also imparts multiple functions to the gel, effectively improving product texture, safety, and storage adaptability, meeting the comprehensive demands of ready-to-eat foods for structural strength, taste, and microbial safety.

[0010] Furthermore, the preparation method of the chitosan / microcrystalline cellulose composite filler is as follows: in parts by weight, 20.0-50.0 parts of chitosan are added to 500.0-1000.0 parts of an acetic acid aqueous solution with a mass concentration of 0.5%-1.0%, and mechanically stirred at a stirring rate of 300.0-500.0 rpm for 0.5-2.0 h at room temperature of 25.0±2.0°C until completely dissolved, to obtain a chitosan solution with a pH value of 3.8-4.2, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed for 15.0-30.0 min using a high-speed shear disperser at a speed of 8000.0-12000.0 rpm to obtain a microcrystalline cellulose suspension, and then 0.1 The pH value of the suspension was adjusted to 5.5-6.0 with mol / L sodium hydroxide aqueous solution. The chitosan solution was slowly added to the microcrystalline cellulose suspension at a rate of 1.0-3.0 mL / min under continuous mechanical stirring. During the addition, the pH value of the system was monitored in real time with a pH meter and maintained in the range of 5.8-6.2. After the addition was completed, high-speed shear dispersion treatment was performed at 6000.0-8000.0 rpm for 1.0-2.0 h to uniformly load the chitosan. The mixture was then centrifuged at 3000.0-5000.0 rpm for 10.0-15.0 min. The supernatant was discarded and the mixture was repeatedly washed with deionized water 2-3 times until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer at -50.0--40.0°C for 12.0-24.0 h, crushed with a grinder, and passed through a 100-200 mesh standard sieve to obtain the target product.

[0011] Furthermore, the preparation method of the microcrystalline cellulose is as follows: in parts by weight, 100.0 parts of cellulose raw material and 800.0~1200.0 parts of a hydrochloric acid aqueous solution with a concentration of 2.5~4.0 mol / L are mixed uniformly in a reactor with a condensing device, and mechanically stirred at a stirring rate of 200.0~400.0 rpm in an atmosphere of normal pressure air, and heated at a heating rate of 5.0~10.0°C / min to a reaction temperature of 100.0~105.0°C for reflux hydrolysis reaction for 2.0~4.0 h, and after the reaction, the system is cooled to room temperature of 25.0±2.0°C at a cooling rate of 3.0~5.0°C / min, and then a pore size of 0.45~0.65 is used. The solid product was separated by filtration through a microporous filter membrane with a diameter of 1 μm, and the solid product was repeatedly washed with deionized water 5 to 8 times until the pH value of the filtrate was 6.5 to 7.5. The washed solid material was then placed in a vacuum drying oven and vacuum dried at 60.0 to 80.0°C for 4.0 to 8.0 hours. Finally, it was processed using a high-speed shear mill at a speed of 10,000 to 15,000 rpm for 30.0 to 60.0 minutes to obtain microcrystalline cellulose.

[0012] Further, the preparation method of the phosphorylated konjac glucomannan is as follows: in parts by weight, 100.0 parts of konjac glucomannan are dispersed in 500.0-800.0 parts of deionized water, mechanically stirred at a stirring speed of 300.0-500.0 rpm in an atmosphere of normal pressure air, and heated to a reaction temperature of 50.0-70.0°C at a heating rate of 3.0-5.0°C / min for 1.0-2.0 h to obtain a uniform colloidal solution, then 15.0-25.0 parts of sodium tripolyphosphate and 8.0-15.0 parts of sodium trimetaphosphate are added in sequence, the pH value of the system is adjusted to 6.8-7.2 with a 0.1 mol / L sodium hydroxide aqueous solution, and then the reaction system is heated to 90.0-95.0°C at a heating rate of 5.0-8.0°C / min, and under this temperature condition, the reaction system is heated to a temperature of 200.0-400.0 The reaction was carried out at rpm for 3.0-5.0 h. During the reaction, a pH meter was used to monitor and maintain the pH value stable. After the reaction, the system was cooled to room temperature (25.0±2.0°C), and then an ethanol aqueous solution with a volume fraction of 85%-95% was added for alcohol precipitation. The precipitate was filtered through a microporous membrane with a pore size of 0.45-0.65 μm and washed 3-5 times with deionized water until the filtrate was neutral. Finally, the product was placed in a vacuum drying oven at 45.0-60.0°C for 8.0-12.0 h, crushed with a grinder, and passed through a 120-200 mesh standard sieve to obtain the phosphorylated konjac glucomannan product.

[0013] The present invention also discloses a method for preparing konjac gel food, comprising the following steps: S1: Accurately weigh the raw materials in parts by weight, add the phosphorylated konjac glucomannan to deionized water, and mechanically stir at 75-85° C. for 1-2 hours to obtain a uniform and transparent colloidal solution; S2: The colloidal solution temperature is adjusted to 60-65°C, chitosan / microcrystalline cellulose composite filler is added, and high-speed shear dispersion technology is used for 10-30 minutes at a speed of 4000-6000 rpm to ensure that the filler is evenly dispersed. Carrageenan and sodium alginate are then added in sequence and stirred at high speed for 10-20 minutes until completely dissolved; S3: The system temperature is adjusted to 50-55° C., and calcium chloride, calcium lactate, citric acid, trisodium citrate, and sodium trimetaphosphate are added in sequence. After each component is added, stirring is performed for 5-10 minutes, and the final pH value is adjusted to 6.5-7.0 with citric acid to obtain a konjac gel precursor. The precursor is then placed in a vacuum environment for degassing for 10-20 minutes at a vacuum degree of -0.08 to -0.10 MPa to remove bubbles in the system. S4: pouring the degassed precursor into a prefabricated mold, allowing it to stand at room temperature for 25 to 35 minutes for preliminary gelation, then placing the initial gel product in a 2 to 6° C. refrigerated environment for curing for 2 to 4 hours, demolding and cutting into predetermined sizes as needed to obtain the konjac gel food.

[0014] Furthermore, in the preparation process, the orderly construction of the layered gel network is achieved by temperature gradient control, wherein the high temperature of 75 to 85° C. in step S1 promotes the full swelling of the phosphorylated konjac glucomannan, the medium temperature of 60 to 65° C. in step S2 ensures the uniform dispersion of the composite filler and the dissolution of the polysaccharide component, the low temperature of 50 to 55° C. in step S3 avoids the thermal inactivation of the cross-linking agent, and the temperature gradient from room temperature to refrigeration in step S4 achieves the gradual solidification and stabilization of the gel network.

[0015] The invention also discloses application of konjac gel food in food simulating the taste of animal cartilage tissue.

[0016] The konjac gel food preparation method disclosed in the present invention is intended to achieve the efficient construction of konjac gel food with uniform structure, stable performance and good sensory quality by accurately controlling the addition order, temperature conditions and dispersion state of each component. The method is by setting the temperature gradient of different stages, for the swelling characteristics of phosphorylated konjac glucomannan, the dispersion characteristics of chitosan / microcrystalline cellulose composite filler and the dissolution and crosslinking conditions of various gel auxiliary components, gradually realizing the orderly transformation from solution state to stable gel network. Wherein, the high temperature treatment in the first stage helps phosphorylated konjac glucomannan to fully unfold the molecular chain and form a uniform colloidal solution, providing a basis for subsequent network construction; the shear dispersion of the composite filler and the full dissolution of the polysaccharide component under medium temperature conditions ensure the uniformity and integrity of the gel skeleton; the low temperature stage effectively avoids the inactivation of the cross-linking agent at high temperature, while optimizing the effect efficiency of the ionic cross-linking components such as calcium ions and sodium trimetaphosphate; finally, by the temperature progressive process from room temperature to refrigeration, the gel system is solidified layer by layer in a relatively mild environment to form a stable three-dimensional network structure. This preparation method not only improves the structural density and rheological resistance of the gel through systematic coordination of process parameters at each stage, but also enhances its performance in simulating the taste of animal cartilage tissue, providing a feasible process path for the development and application of konjac-based functional foods.

[0017] (3) Beneficial technical effects 1. The present invention significantly improves the structural stability and biomimetic taste of konjac gel through the precise matching of multi-component synergy and temperature control process, and solves the problems of poor brittleness and weak processing adaptability of existing gels. It is suitable for the development of high-end plant-based foods.

[0018] 2. The present invention realizes a konjac gel food with stable structure and excellent taste through component synergy and temperature control process optimization, effectively solving the problems of poor brittleness and weak stability of existing products. It is suitable for a variety of bionic food scenarios and has significant application and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a morphology diagram of the microcrystalline cellulose prepared in Example 1 of the present invention.

[0020] Figure 2 This is the XRD phase analysis diagram of the microcrystalline cellulose prepared in Example 1 of the present invention.

[0021] Figure 3 This is a morphology picture of the chitosan / microcrystalline cellulose composite filler prepared in Example 1 of the present invention.

[0022] Figure 4 This is the XRD phase analysis diagram of the polysaccharide / microcrystalline cellulose composite filler prepared in Example 1 of the present invention.

[0023] Figure 5 This is a microstructure morphology diagram of the konjac gel food prepared in Example 1 of the present invention.

[0024] Figure 6 This is a physical picture of the triangular chicken gristle konjac gel food prepared in Example 1 of the present invention.

[0025] Figure 7 The figure is a comparison chart of the storage modulus and the breaking strength of the examples of the present invention and the comparative examples.

[0026] Figure 8 1 is a comparison chart of the relationship between the brittleness index and the water separation rate of the embodiments of the present invention and the comparative example.

[0027] Figure 9 1 is a comparison chart of the correlation between the storage modulus and the antibacterial performance of the embodiments of the present invention and the comparative examples.

[0028] Figure 10 2 is a comparison chart of the diameters of the inhibition zones of the embodiments of the present invention and the comparative examples. DETAILED DESCRIPTION

[0029] To make the objectives, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0030] Example 1 A konjac gel food comprises the following raw materials in parts by weight: 50.0 parts of phosphorylated konjac glucomannan, 25.0 parts of chitosan / microcrystalline cellulose composite filler, 2.0 parts of calcium chloride, 1.0 part of trisodium citrate, 1.0 part of citric acid, 1.0 part of sodium trimetaphosphate, 2.0 parts of carrageenan, 2.0 parts of sodium alginate, 1.0 part of calcium lactate, and 200.0 parts of deionized water; Phosphorylated konjac glucomannan is obtained by reacting konjac glucomannan with phosphate, followed by drying and crushing; the chitosan / microcrystalline cellulose composite filler is composed of microcrystalline cellulose and chitosan particles loaded on the surface of microcrystalline cellulose, and achieves a synergistic effect of enhanced stability and improved brittleness through a multiple cross-linked network structure.

[0031] The mass ratio of microcrystalline cellulose to chitosan in the chitosan / microcrystalline cellulose composite filler of this embodiment is 1.0:0.5; The average length of the chitosan / microcrystalline cellulose composite filler particles is 16 μm, and the average diameter is 2.0 μm.

[0032] The phosphates in this embodiment are sodium tripolyphosphate and sodium trimetaphosphate; The phosphorylation degree of the phosphorylated konjac glucomannan in this example is 0.09; the introduction of phosphate groups enhances the intermolecular hydrogen bonding and ionic cross-linking effects.

[0033] The preparation method of the chitosan / microcrystalline cellulose composite filler of this embodiment is as follows: 29 parts of chitosan are added to 650 parts of acetic acid aqueous solution with a mass concentration of 0.6%, and mechanically stirred at a stirring rate of 360 rpm for 0.9 h at room temperature of 25.0±2.0°C until completely dissolved to obtain a chitosan solution with a pH value of 3.9, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed at a speed of 9200 rpm for 19.5 min using a high-speed shear disperser to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 5.6 with a 0.1 mol / L sodium hydroxide aqueous solution, and the chitosan solution is slowly added to the microcrystalline cellulose suspension at a dropping rate of 1.6 mL / min under continuous mechanical stirring. During the dropping process, a pH meter is used to monitor and maintain the pH value of the system within the range of 5.9 in real time. After the dropwise addition is completed, a high-speed shear dispersion treatment of 6600 rpm is used for 1.3 h to uniformly load the chitosan, and then the mixture is centrifuged at a speed of 3600 The mixture was centrifuged at rpm for 11.5 min, the supernatant was discarded and washed twice with deionized water until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer and dried at -47°C for 15.6 h. After being crushed by a grinder, the target product was obtained by passing through a 130-mesh standard sieve.

[0034] The preparation method of microcrystalline cellulose in this embodiment is as follows: 100.0 parts of cellulose raw material and 920 parts of 2.9 mol / L hydrochloric acid aqueous solution are mixed uniformly in a reactor equipped with a condensing device, and mechanically stirred at a stirring rate of 260 rpm in an atmospheric air atmosphere. At the same time, the mixture is heated to a reaction temperature of 101.5°C at a heating rate of 6.5°C / min and reflux hydrolysis reaction is carried out for 2.6 h. After the reaction is completed, the system is cooled to room temperature of 25.0±2.0°C at a cooling rate of 3.6°C / min, and then filtered and separated using a microporous membrane with a pore size of 0.51 μm. The solid product is repeatedly washed with deionized water 6 times until the pH value of the filtrate is 6.8, and then the washed solid material is placed in a vacuum drying oven and vacuum dried at 66°C for 5.2 h. Finally, it is processed using a high-speed shear mill at a speed of 11500 rpm for 39 min to obtain microcrystalline cellulose.

[0035] The preparation method of the phosphorylated konjac glucomannan of the present embodiment is as follows: in parts by weight, 100.0 parts of konjac glucomannan are dispersed in 590 parts of deionized water, mechanically stirred at a stirring speed of 360 rpm in an atmosphere of normal pressure air, and heated to a reaction temperature of 56 ° C for 1.3 h at a heating rate of 3.6 ° C / min to obtain a uniform colloidal solution, then 18 parts of sodium tripolyphosphate and 10.1 parts of sodium trimetaphosphate are added in sequence, the pH value of the system is adjusted to 6.9 with a 0.1 mol / L sodium hydroxide aqueous solution, then the reaction system is heated to 91.5 ° C at a heating rate of 5.9 ° C / min, and the reaction is carried out at a stirring speed of 260 rpm for 3.6 h under this temperature condition. During the reaction, a pH meter is used to monitor and maintain the pH value stable in real time. After the reaction is completed, the system is cooled to room temperature of 25.0 ± 2.0 ° C, and then an ethanol aqueous solution with a volume fraction of 88% is added for alcohol precipitation separation. The precipitate is separated through a pore size of 0.51 After filtration through a microporous membrane with a diameter of 1 μm, the product was washed four times with deionized water until the filtrate was neutral. Finally, the product was dried in a vacuum drying oven at 49.5°C for 9.2 h, crushed with a grinder, and passed through a 144-mesh standard sieve to obtain the phosphorylated konjac glucomannan product.

[0036] The preparation method of a kind of konjac gel food of the present embodiment comprises the following steps: S1: Accurately weigh the raw materials in parts by weight, add the phosphorylated konjac glucomannan to deionized water, and mechanically stir at 78° C. for 1.3 hours to obtain a uniform and transparent colloidal solution; S2: The colloidal solution temperature was adjusted to 62°C, chitosan / microcrystalline cellulose composite filler was added, and high-speed shear dispersion technology was used for 16 minutes at a speed of 4600 rpm to ensure uniform dispersion of the filler. Carrageenan and sodium alginate were then added in sequence and stirred at high speed for 13 minutes until completely dissolved; S3: The system temperature was adjusted to 52° C., and calcium chloride, calcium lactate, citric acid, trisodium citrate, and sodium trimetaphosphate were added in sequence. After each component was added, stirring was continued for 6.5 minutes. The final pH value was adjusted to 6.6 with citric acid to obtain a konjac gel precursor. The precursor was then placed in a vacuum environment for degassing for 13 minutes at a vacuum degree of -0.086 MPa to remove bubbles in the system. S4: pouring the degassed precursor into a prefabricated mold and allowing it to stand at room temperature for 28 minutes for preliminary gelation, then placing the initial gel product in a 3.2° C. refrigerated environment for curing for 2.6 hours, demolding and cutting into predetermined sizes as needed to obtain the konjac gel food.

[0037] In this embodiment, the orderly construction of a layered gel network is achieved by temperature gradient control, wherein the high temperature of 78°C in step S1 promotes the full swelling of phosphorylated konjac glucomannan, the medium temperature of 62°C in step S2 ensures the uniform dispersion of the composite filler and the dissolution of the polysaccharide component, the low temperature of 52°C in step S3 avoids thermal inactivation of the cross-linking agent, and the temperature gradient from room temperature to refrigeration in step S4 achieves the gradual solidification and stabilization of the gel network.

[0038] Example 2 A konjac gel food comprises the following raw materials in parts by weight: 65 parts of phosphorylated konjac glucomannan, 30 parts of chitosan / microcrystalline cellulose composite filler, 3 parts of calcium chloride, 2 parts of trisodium citrate, 2 parts of citric acid, 2 parts of sodium trimetaphosphate, 4 parts of carrageenan, 3 parts of sodium alginate, 2 parts of calcium lactate, and 260 parts of deionized water; Phosphorylated konjac glucomannan is obtained by reacting konjac glucomannan with phosphate, followed by drying and crushing; the chitosan / microcrystalline cellulose composite filler is composed of microcrystalline cellulose and chitosan particles loaded on the surface of microcrystalline cellulose, and achieves a synergistic effect of enhanced stability and improved brittleness through a multiple cross-linked network structure.

[0039] The mass ratio of microcrystalline cellulose to chitosan in the chitosan / microcrystalline cellulose composite filler of this embodiment is 2.2:1.0; The average particle length of the chitosan / microcrystalline cellulose composite filler is 26 μm and the average diameter is 2.9 μm. The phosphates in this embodiment are sodium tripolyphosphate and sodium trimetaphosphate; The phosphorylation degree of the phosphorylated konjac glucomannan in this example is 0.04; the introduction of phosphate groups enhances the intermolecular hydrogen bonding and ionic cross-linking effects.

[0040] The preparation method of the chitosan / microcrystalline cellulose composite filler of the present embodiment is as follows: in parts by weight, 20.0 parts of chitosan are added to 500.0 parts of an aqueous solution of acetic acid with a mass concentration of 0.5%, and mechanically stirred at a stirring rate of 300.0 rpm for 0.5 h at room temperature of 25.0±2.0°C until completely dissolved to obtain a chitosan solution with a pH value of 3.8, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed for 15.0 min at a speed of 8000.0 rpm using a high-speed shear disperser to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 5.5 with a 0.1 mol / L aqueous sodium hydroxide solution, and the chitosan solution is slowly added to the microcrystalline cellulose suspension at a dropping rate of 1.0 mL / min under continuous mechanical stirring. During the dropping process, a pH meter is used to monitor and maintain the pH value of the system within the range of 5.8. After the dropwise addition is completed, a high-speed shear dispersion treatment of 1.0 at 6000.0 rpm is used. h to uniformly load the chitosan, and then the mixture was centrifuged at a centrifugal speed of 3000.0 rpm for 10.0 min. The supernatant was discarded and washed twice with deionized water until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer and dried at -50.0°C for 12.0 h. After being crushed by a grinder, it was passed through a 100-mesh standard sieve to obtain the target product.

[0041] The preparation method of microcrystalline cellulose in this embodiment is as follows: 100.0 parts of cellulose raw material and 800.0 parts of 2.5 mol / L hydrochloric acid aqueous solution are mixed uniformly in a reactor equipped with a condensing device, and mechanically stirred at a stirring rate of 200.0 rpm in an atmosphere of normal pressure air. At the same time, the mixture is heated to a reaction temperature of 100.0°C at a heating rate of 5.0°C / min and reflux hydrolysis reaction is carried out for 2.0 h. After the reaction is completed, the system is cooled to room temperature of 25.0±2.0°C at a cooling rate of 3.0°C / min, and then filtered and separated using a microporous membrane with a pore size of 0.45 μm. The solid product is repeatedly washed with deionized water 5 times until the pH value of the filtrate is 6.5, and then the washed solid material is placed in a vacuum drying oven and vacuum dried at 60.0°C for 4.0 h. Finally, it is treated with a high-speed shear mill at a speed of 10000.0 rpm for 30.0 min to obtain microcrystalline cellulose.

[0042] The preparation method of the phosphorylated konjac glucomannan of the present embodiment is as follows: 100.0 parts of konjac glucomannan are dispersed in 500.0 parts of deionized water, mechanically stirred at a stirring rate of 300.0 rpm in an atmosphere of normal pressure air, and heated to a reaction temperature of 50.0°C at a heating rate of 3.0°C / min for 1.0 h to obtain a uniform colloidal solution, then 15.0 parts of sodium tripolyphosphate and 8.0 parts of sodium trimetaphosphate are added in sequence, the pH value of the system is adjusted to 6.8 with a 0.1 mol / L sodium hydroxide aqueous solution, and then the reaction system is heated to 90.0°C at a heating rate of 5.0°C / min, and the reaction is continued for 3.0 h at a stirring rate of 200.0 rpm. h. During the reaction, a pH meter was used to monitor and maintain the pH value stable in real time. After the reaction, the system was cooled to room temperature (25.0±2.0°C), and then an 85% by volume ethanol aqueous solution was added for alcohol precipitation separation. The precipitate was filtered through a microporous filter membrane with a pore size of 0.45 μm and washed three times with deionized water until the filtrate was neutral. Finally, the product was placed in a vacuum drying oven at 45.0°C for 8.0 h, crushed with a grinder, and passed through a 120-mesh standard sieve to obtain the phosphorylated konjac glucomannan product.

[0043] The preparation method of a kind of konjac gel food of the present embodiment comprises the following steps: S1: Accurately weigh the raw materials in parts by weight, add the phosphorylated konjac glucomannan to deionized water, and mechanically stir at 75° C. for 1 hour to obtain a uniform and transparent colloidal solution; S2: The temperature of the colloidal solution was adjusted to 60°C, chitosan / microcrystalline cellulose composite filler was added, and high-speed shear dispersion technology was used for 10 minutes at a speed of 4000 rpm to ensure that the filler was evenly dispersed. Carrageenan and sodium alginate were then added in sequence and stirred at high speed for 10 minutes until they were completely dissolved. S3: The system temperature was adjusted to 50° C., and calcium chloride, calcium lactate, citric acid, trisodium citrate, and sodium trimetaphosphate were added in sequence. After each component was added, stirring was continued for 5 minutes. The final pH value was adjusted to 6.5 with citric acid to obtain a konjac gel precursor. The precursor was then placed in a vacuum environment for degassing for 10 minutes at a vacuum degree of -0.08 MPa to remove bubbles in the system. S4: pouring the degassed precursor into a prefabricated mold and allowing it to stand at room temperature for 25 minutes for preliminary gelation, then placing the initial gel product in a 2° C. refrigerated environment for curing for 2 hours, demolding and cutting into predetermined sizes as needed to obtain the konjac gel food.

[0044] In this embodiment, the orderly construction of a layered gel network is achieved by temperature gradient control, wherein the high temperature of 75°C in step S1 promotes the full swelling of phosphorylated konjac glucomannan, the medium temperature of 60°C in step S2 ensures the uniform dispersion of the composite filler and the dissolution of the polysaccharide component, the low temperature of 50°C in step S3 avoids thermal inactivation of the cross-linking agent, and the temperature gradient from room temperature to refrigeration in step S4 achieves the gradual solidification and stabilization of the gel network.

[0045] Example 3 A konjac gel food comprises the following raw materials in parts by weight: 100.0 parts of phosphorylated konjac glucomannan, 50.0 parts of chitosan / microcrystalline cellulose composite filler, 6.0 parts of calcium chloride, 4.0 parts of trisodium citrate, 5.0 parts of citric acid, 3.0 parts of sodium trimetaphosphate, 8.0 parts of carrageenan, 6.0 parts of sodium alginate, 3.0 parts of calcium lactate, and 400.0 parts of deionized water; Phosphorylated konjac glucomannan is obtained by reacting konjac glucomannan with phosphate, followed by drying and crushing; the chitosan / microcrystalline cellulose composite filler is composed of microcrystalline cellulose and chitosan particles loaded on the surface of microcrystalline cellulose, and achieves a synergistic effect of enhanced stability and improved brittleness through a multiple cross-linked network structure.

[0046] The mass ratio of microcrystalline cellulose to chitosan in the chitosan / microcrystalline cellulose composite filler of this embodiment is 5.0:2.5; The average length of the chitosan / microcrystalline cellulose composite filler particles is 50 μm, and the average diameter is 5.0 μm.

[0047] The phosphates in this embodiment are sodium tripolyphosphate and sodium trimetaphosphate; The phosphorylation degree of the phosphorylated konjac glucomannan in this example is 0.20; the introduction of phosphate groups enhances the intermolecular hydrogen bonding and ionic cross-linking effects.

[0048] The preparation method of the chitosan / microcrystalline cellulose composite filler of the present embodiment is as follows: in parts by weight, 50.0 parts of chitosan are added to 1000.0 parts of an acetic acid aqueous solution with a mass concentration of 1.0%, and mechanically stirred at a stirring rate of 500.0 rpm for 2.0 h at room temperature of 25.0±2.0°C until completely dissolved to obtain a chitosan solution with a pH value of 4.2, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed for 30.0 min at a speed of 12000.0 rpm using a high-speed shear disperser to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 6.0 with a 0.1 mol / L sodium hydroxide aqueous solution, and the chitosan solution is slowly added to the microcrystalline cellulose suspension at a dropping rate of 3.0 mL / min under continuous mechanical stirring. During the dropping process, a pH meter is used to monitor and maintain the pH value of the system within the range of 6.2 in real time. After the dropwise addition is completed, a high-speed shear dispersion treatment of 8000.0 rpm is used for 2.0 h to uniformly load the chitosan, and then the mixture was centrifuged at a centrifugal speed of 5000.0 rpm for 15.0 min. The supernatant was discarded and washed repeatedly with deionized water three times until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer and dried at -40.0°C for 24.0 h. After being crushed by a grinder, it was passed through a 200-mesh standard sieve to obtain the target product.

[0049] The preparation method of microcrystalline cellulose in this embodiment is as follows: 100.0 parts of cellulose raw material and 1200.0 parts of 4.0 mol / L hydrochloric acid aqueous solution are mixed uniformly in a reactor equipped with a condensing device, and mechanically stirred at a stirring rate of 400.0 rpm in an atmospheric air atmosphere. At the same time, the mixture is heated to a reaction temperature of 105.0°C at a heating rate of 10.0°C / min and reflux hydrolysis reaction is carried out for 4.0 h. After the reaction is completed, the system is cooled to room temperature of 25.0±2.0°C at a cooling rate of 5.0°C / min, and then filtered and separated using a microporous membrane with a pore size of 0.65 μm. The solid product is repeatedly washed 8 times with deionized water until the pH value of the filtrate is 7.5, and then the washed solid material is placed in a vacuum drying oven and vacuum dried at 80.0°C for 8.0 h. Finally, a high-speed shear mill is used at a speed of 15000.0 rpm for 60.0 min to obtain microcrystalline cellulose.

[0050] The preparation method of the phosphorylated konjac glucomannan of the present embodiment is as follows: 100.0 parts of konjac glucomannan are dispersed in 800.0 parts of deionized water, mechanically stirred at a stirring rate of 500.0 rpm in an atmosphere of normal pressure air, and heated to a reaction temperature of 70.0°C at a heating rate of 5.0°C / min for 2.0 h to obtain a uniform colloidal solution, then 25.0 parts of sodium tripolyphosphate and 15.0 parts of sodium trimetaphosphate are added in sequence, the pH value of the system is adjusted to 7.2 with a 0.1 mol / L sodium hydroxide aqueous solution, and then the reaction system is heated to 95.0°C at a heating rate of 8.0°C / min, and the reaction is continued for 5.0 h at a stirring rate of 400.0 rpm. h. During the reaction, a pH meter was used to monitor and maintain the pH value stable in real time. After the reaction, the system was cooled to room temperature (25.0±2.0°C), and then a 95% by volume ethanol aqueous solution was added for alcohol precipitation separation. The precipitate was filtered through a microporous filter membrane with a pore size of 0.65 μm and washed five times with deionized water until the filtrate was neutral. Finally, the product was placed in a vacuum drying oven at 60.0°C for 12.0 h, crushed with a grinder, and passed through a 200-mesh standard sieve to obtain the phosphorylated konjac glucomannan product.

[0051] The preparation method of a kind of konjac gel food of the present embodiment comprises the following steps: S1: Accurately weigh the raw materials in parts by weight, add the phosphorylated konjac glucomannan to deionized water, and mechanically stir at 85° C. for 2 hours to obtain a uniform and transparent colloidal solution; S2: The colloidal solution temperature was adjusted to 65°C, chitosan / microcrystalline cellulose composite filler was added, and high-speed shear dispersion technology was used for 30 minutes at a speed of 6000 rpm to ensure that the filler was evenly dispersed. Carrageenan and sodium alginate were then added in sequence and stirred at high speed for 20 minutes until completely dissolved; S3: The system temperature was adjusted to 55° C., and calcium chloride, calcium lactate, citric acid, trisodium citrate, and sodium trimetaphosphate were added in sequence. Each component was stirred for 10 minutes after addition, and the final pH value was adjusted to 7.0 with citric acid to obtain a konjac gel precursor. The precursor was then placed in a vacuum environment for degassing for 20 minutes at a vacuum degree of -0.10 MPa to remove bubbles in the system. S4: Pour the degassed precursor into a prefabricated mold and allow it to stand at room temperature for 35 minutes for preliminary gelation. Then, place the initial gel product in a 6°C cold storage environment for curing for 4 hours, demold and cut into predetermined sizes as needed to obtain the konjac gel food.

[0052] In this embodiment, the orderly construction of a layered gel network is achieved by temperature gradient control, wherein the high temperature of 85°C in step S1 promotes the full swelling of phosphorylated konjac glucomannan, the medium temperature of 65°C in step S2 ensures the uniform dispersion of the composite filler and the dissolution of the polysaccharide component, the low temperature of 55°C in step S3 avoids the thermal inactivation of the cross-linking agent, and the temperature gradient from room temperature to refrigeration in step S4 achieves the gradual solidification and stabilization of the gel network.

[0053] Example 4 A konjac gel food comprises the following raw materials in parts by weight: 100.0 parts of phosphorylated konjac glucomannan, 40.0 parts of chitosan / microcrystalline cellulose composite filler, 6.0 parts of calcium chloride, 4.0 parts of trisodium citrate, 5.0 parts of citric acid, 3.0 parts of sodium trimetaphosphate, 8.0 parts of carrageenan, 6.0 parts of sodium alginate, 3.0 parts of calcium lactate, and 400.0 parts of deionized water; Phosphorylated konjac glucomannan is obtained by reacting konjac glucomannan with phosphate, followed by drying and crushing; the chitosan / microcrystalline cellulose composite filler is composed of microcrystalline cellulose and chitosan particles loaded on the surface of microcrystalline cellulose, and achieves a synergistic effect of enhanced stability and improved brittleness through a multiple cross-linked network structure.

[0054] The mass ratio of microcrystalline cellulose to chitosan in the chitosan / microcrystalline cellulose composite filler of this embodiment is 5.0:2.0; The average length of the chitosan / microcrystalline cellulose composite filler particles is 50 μm, and the average diameter is 5.0 μm.

[0055] The phosphates in this embodiment are sodium tripolyphosphate and sodium trimetaphosphate; The phosphorylation degree of the phosphorylated konjac glucomannan in this example is 0.14; the introduction of phosphate groups enhances the intermolecular hydrogen bonding and ionic cross-linking effects.

[0056] The preparation method of the chitosan / microcrystalline cellulose composite filler of the present embodiment is as follows: 38 parts of chitosan are added to 800 parts of acetic acid aqueous solution with a mass concentration of 0.8%, and mechanically stirred at a stirring rate of 420 rpm for 1.4 h at room temperature of 25.0±2.0°C until completely dissolved to obtain a chitosan solution with a pH value of 4.0, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed at a speed of 10400 rpm for 24 min using a high-speed shear disperser to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 5.8 with a 0.1 mol / L sodium hydroxide aqueous solution, and the chitosan solution is slowly added to the microcrystalline cellulose suspension at a dropping rate of 2.2 mL / min under continuous mechanical stirring. During the dropping process, a pH meter is used to monitor and maintain the pH value of the system within the range of 6.0 in real time. After the dropwise addition is completed, a high-speed shear dispersion treatment of 7200 rpm is used for 1.6 h to uniformly load the chitosan, and then the mixture is centrifuged at a speed of 4200 The mixture was centrifuged at rpm for 13 min, the supernatant was discarded and washed three times with deionized water until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer and dried at -43°C for 19.2 h. After being crushed by a grinder, the target product was obtained by passing through a 160-mesh standard sieve.

[0057] The preparation method of microcrystalline cellulose in this embodiment is as follows: 100.0 parts of cellulose raw material and 1040 parts of 3.4 mol / L hydrochloric acid aqueous solution are mixed uniformly in a reactor equipped with a condensing device, and mechanically stirred at a stirring rate of 320 rpm in an atmospheric air atmosphere. At the same time, the mixture is heated to a reaction temperature of 103°C at a heating rate of 8°C / min and reflux hydrolysis reaction is carried out for 3.2 h. After the reaction is completed, the system is cooled to room temperature of 25.0±2.0°C at a cooling rate of 4.2°C / min, and then filtered and separated using a microporous membrane with a pore size of 0.57 μm. The solid product is repeatedly washed with deionized water 7 times until the pH value of the filtrate is 7.1, and then the washed solid material is placed in a vacuum drying oven and vacuum dried at 72°C for 6.4 h. Finally, it is processed using a high-speed shear mill at a speed of 13,000 rpm for 48 min to obtain microcrystalline cellulose.

[0058] The preparation method of the phosphorylated konjac glucomannan of the present embodiment is as follows: in parts by weight, 100.0 parts of konjac glucomannan are dispersed in 680 parts of deionized water, mechanically stirred at a stirring speed of 420 rpm in an atmosphere of normal pressure air, and heated to a reaction temperature of 62 ° C for 1.6 h at a heating rate of 4.2 ° C / min to obtain a uniform colloidal solution, then 21 parts of sodium tripolyphosphate and 12.2 parts of sodium trimetaphosphate are added in sequence, the pH value of the system is adjusted to 7.0 with a 0.1 mol / L sodium hydroxide aqueous solution, then the reaction system is heated to 93 ° C at a heating rate of 6.8 ° C / min, and the reaction is carried out at a stirring speed of 320 rpm for 4.2 h under this temperature condition. During the reaction, a pH meter is used to monitor and maintain the pH value stable in real time. After the reaction is completed, the system is cooled to room temperature of 25.0 ± 2.0 ° C, and then a 91% ethanol aqueous solution by volume is added for alcohol precipitation separation. The precipitate is separated by a pore size of 0.57 After filtration through a microporous membrane with a diameter of 1 μm, the product was washed four times with deionized water until the filtrate was neutral. Finally, the product was dried in a vacuum drying oven at 54°C for 10.4 h, crushed with a grinder, and passed through a 168-mesh standard sieve to obtain the phosphorylated konjac glucomannan product.

[0059] The preparation method of a kind of konjac gel food of the present embodiment comprises the following steps: S1: Accurately weigh the raw materials in parts by weight, add the phosphorylated konjac glucomannan to deionized water, and mechanically stir at 81° C. for 1.6 hours to obtain a uniform and transparent colloidal solution; S2: The colloidal solution temperature was adjusted to 63°C, chitosan / microcrystalline cellulose composite filler was added, and high-speed shear dispersion technology was used for 22 minutes at a speed of 5200 rpm to ensure uniform dispersion of the filler. Carrageenan and sodium alginate were then added in sequence and stirred at high speed for 16 minutes until completely dissolved; S3: The system temperature was adjusted to 53° C., and calcium chloride, calcium lactate, citric acid, trisodium citrate, and sodium trimetaphosphate were added in sequence. Each component was stirred for 8 minutes after addition, and the final pH value was adjusted to 6.8 with citric acid to obtain a konjac gel precursor. The precursor was then placed in a vacuum environment for degassing for 16 minutes at a vacuum degree of -0.092 MPa to remove bubbles in the system. S4: Pour the degassed precursor into a prefabricated mold and allow it to stand at room temperature for 31 minutes for preliminary gelation. Then, place the initial gel product in a 4.4°C cold storage environment for curing for 3.2 hours, demold and cut into predetermined sizes as needed to obtain the konjac gel food.

[0060] In this embodiment, the orderly construction of a layered gel network is achieved by temperature gradient control, wherein the high temperature of 81°C in step S1 promotes the full swelling of phosphorylated konjac glucomannan, the medium temperature of 63°C in step S2 ensures the uniform dispersion of the composite filler and the dissolution of the polysaccharide component, the low temperature of 53°C in step S3 avoids thermal inactivation of the cross-linking agent, and the temperature gradient from room temperature to refrigeration in step S4 achieves the gradual solidification and stabilization of the gel network.

[0061] Comparative Example 1 The method is basically the same as Example 1, except that 50.0 parts of ordinary konjac glucomannan that has not been phosphorylated is used instead of phosphorylated konjac glucomannan, sodium tripolyphosphate and sodium trimetaphosphate are not added, and the other components and amounts remain unchanged.

[0062] Comparative Example 2 The method is basically the same as Example 1, except that no chitosan / microcrystalline cellulose composite filler is used. Instead, 25.0 parts of microcrystalline cellulose is used alone as the filler. The chitosan particles loaded on the surface of the microcrystalline cellulose are not included. The other components and amounts remain unchanged.

[0063] Comparative Example 3 The method is basically the same as Example 1, except that the mass ratio of microcrystalline cellulose to chitosan in the chitosan / microcrystalline cellulose composite filler is 10.0:0.2, and the other preparation processes and component amounts remain unchanged.

[0064] The preparation method of the chitosan / microcrystalline cellulose composite filler of this comparative example is as follows: in parts by weight, 20 parts of chitosan are added to 650 parts of acetic acid aqueous solution with a mass concentration of 0.6%, and mechanically stirred at a stirring rate of 360 rpm for 0.9 h at room temperature of 25.0±2.0°C until completely dissolved to obtain a chitosan solution with a pH value of 3.9, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed at a speed of 9200 rpm for 19.5 min using a high-speed shear disperser to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 5.6 with a 0.1 mol / L sodium hydroxide aqueous solution, and the chitosan solution is slowly added to the microcrystalline cellulose suspension at a dropping rate of 1.6 mL / min under continuous mechanical stirring. During the dropping process, a pH meter is used to monitor and maintain the pH value of the system within the range of 5.9 in real time. After the dropwise addition is completed, a high-speed shear dispersion treatment of 6600 rpm is used for 1.3 h to uniformly load the chitosan, and then the mixture is centrifuged at a speed of 3600 The mixture was centrifuged at rpm for 11.5 min, the supernatant was discarded and washed twice with deionized water until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer and dried at -47°C for 15.6 h. After being crushed by a grinder, the target product was obtained by passing through a 130-mesh standard sieve.

[0065] Comparative Example 4 The method is basically the same as Example 1, except that the average length of the chitosan / microcrystalline cellulose composite filler particles is 80 μm, the average diameter is 8.0 μm, and the other preparation parameters remain unchanged.

[0066] The preparation method of the chitosan / microcrystalline cellulose composite filler of this comparative example is as follows: 29 parts of chitosan are added to 650 parts of acetic acid aqueous solution with a mass concentration of 0.6%, and mechanically stirred at a stirring rate of 360 rpm for 0.9 h at room temperature of 25.0±2.0°C until completely dissolved to obtain a chitosan solution with a pH value of 3.9, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed at a speed of 9200 rpm for 19.5 min using a high-speed shear disperser to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 5.6 with a 0.1 mol / L sodium hydroxide aqueous solution, and the chitosan solution is slowly added to the microcrystalline cellulose suspension at a dropping rate of 1.6 mL / min under continuous mechanical stirring. During the dropping process, a pH meter is used to monitor and maintain the pH value of the system within the range of 5.9 in real time. After the dropwise addition is completed, a high-speed shear dispersion treatment of 6600 rpm is used for 1.3 h to uniformly load the chitosan, and then the mixture is centrifuged at a speed of 3600 The mixture was centrifuged at rpm for 11.5 min, the supernatant was discarded and the filtrate was washed twice with deionized water until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer and dried at -47°C for 15.6 h. After being crushed by a grinder and sieved, the target product with an average particle length of 80 μm and an average diameter of 8.0 μm was obtained.

[0067] The preparation method of microcrystalline cellulose in this comparative example is the same as that in Example 1.

[0068] Comparative Example 5 The method is basically the same as Example 1, except that the mass ratio of phosphorylated konjac glucomannan to chitosan / microcrystalline cellulose composite filler is 6:0.3.

[0069] Comparative Example 6 The process is basically the same as Example 1, except that the phosphorylation degree of the phosphorylated konjac glucomannan is 0.35, and 35.0 parts of sodium tripolyphosphate and 25.0 parts of sodium trimetaphosphate are used in the phosphorylation reaction.

[0070] Comparative Example 7 The method is basically the same as Example 1, except that the mass concentration of the acetic acid aqueous solution during the preparation of the chitosan / microcrystalline cellulose composite filler is 2.0%.

[0071] Comparative Example 8 The method is basically the same as Example 1, except that the concentration of the hydrochloric acid aqueous solution during the preparation of microcrystalline cellulose is 1.5 mol / L.

[0072] Comparative Example 9 The method is basically the same as Example 1, except that the reaction temperature during the preparation of phosphorylated konjac glucomannan is 40.0°C.

[0073] Comparative Example 10 Basically the same as Example 1, difference is that in the konjac gel food preparation process, the temperature of step S1 is 70 ℃, and the temperature of step S2 is 70 ℃.

[0074] Performance testing: Thermal Stability Test (Test Target: Structural Stability of Konjac Gel): To assess the structural stability of konjac gel during processing and storage, dynamic mechanical analysis (DMA) was used to measure its storage modulus (E′) and loss factor (tan δ) at different temperatures, analyzing the gel's thermal response and structural retention. The test was conducted at a heating rate of 3°C / min over a temperature range of 20–100°C. The changes in the elastic modulus of the gel under varying temperature gradients were recorded to reflect its thermal stability. This method is based on ASTM D7028.

[0075] Mechanical brittleness testing (test subject: brittleness and fracture properties of konjac gel): A compression-puncture test was performed on gel samples using a texture analyzer to determine their fracture strength and brittleness index. Using a standard puncture probe (e.g., P / 2N) and a compression speed of 1 mm / s, the force and fracture pattern corresponding to the sample's fracture point in the puncture force-displacement curve were recorded. This method effectively reflects the fracture characteristics of gels during simulated oral chewing.

[0076] Water Retention and Water Separation Test (Test Target: Storage Stability of Konjac Gel): To evaluate the storage stability of konjac gel at room temperature or refrigerated conditions, centrifugation and static weighing methods can be used to determine its water retention and water separation rate. A quantitative gel sample is placed in a centrifuge tube and centrifuged at 5000 rpm for 10 minutes. The supernatant is collected and the water separation percentage is calculated. The change in sample mass at different time points is then used to evaluate the gel's water retention capacity.

[0077] Antibacterial Activity Testing (Test Subject: Antibacterial Activity of Konjac Gel): The antibacterial properties of konjac gel were evaluated using the inhibition zone method (agar diffusion method) and colony count method. Indicator bacteria, such as Escherichia coli and Staphylococcus aureus, were inoculated on the surface of an agar medium. Chitosan-containing gel samples were then placed on the surface. After 24 hours of incubation, the diameter of the inhibition zone was measured. Furthermore, the antibacterial efficacy was further verified by comparing the reduction rate of colony-forming units (CFU) after inoculation with that of the control group.

[0078] Sensory evaluation (test object: edible quality of gel): A professional sensory panel of at least 10 people was organized to evaluate crispness, springiness, and overall acceptability using a 9-point scale (ISO 8586:2012), with a focus on analyzing the correlation between crispness and gel strength.

[0079] The properties of the konjac gels of Examples 1 to 4 and Comparative Examples 1 to 10 are summarized in Table 1. The rationality of the present invention is fully confirmed through system morphology, phase analysis and performance test characterization. Figure 1-2 The microscopic morphology and crystal structure characteristics of microcrystalline cellulose are clearly displayed, verifying the high purity and good crystallinity of the raw material; Figure 3-4 The successful composite of chitosan and microcrystalline cellulose and their synergistic effect were further confirmed, showing the uniform dispersion and enhanced crystalline structure of the composite filler; Figure 5-6 It intuitively presents the microscopic network structure and actual finished product quality of the final konjac gel food. Figure 7-9 The performance comparison data quantitatively verifies the technical advantages of the present invention, in which the storage modulus and fracture strength are synergistically improved ( Figure 7 ), the brittleness index and water separation rate show an ideal negative correlation ( Figure 8 ), while the storage modulus is positively correlated with the antibacterial performance ( Figure 9) confirmed the innovative value of the product of the present invention in having both excellent mechanical properties and antibacterial properties. These correlation analysis results collectively indicate that the konjac gel food prepared by the present invention has achieved significant improvements in structural stability, texture properties and functionality. As can be seen from Table 1, due to the direct use of ordinary konjac glucomannan instead of phosphorylated konjac glucomannan, the cross-linking density and stability of the gel network structure are significantly reduced, the thermal stability is reduced, and the moisture retention capacity is weakened. At the same time, the lack of the introduction of phosphate groups makes the antibacterial performance obviously insufficient. Since microcrystalline cellulose is used as a filler instead of chitosan / microcrystalline cellulose composite filler, the natural antibacterial activity of chitosan and the synergistic enhancement effect with konjac glucomannan are lost, resulting in a sharp decline in antibacterial performance, and the mechanical strength and brittleness performance are also negatively affected. When the mass ratio of chitosan to microcrystalline cellulose is too low, the chitosan loading amount is insufficient, and the reinforcing and antibacterial effects of the composite filler cannot be fully exerted, and the overall performance improvement is limited. When the composite filler particle size is too large, it is unevenly dispersed in the gel matrix, and stress concentration points are easily formed, which reduces the mechanical properties and thermal stability of the gel. At the same time, the presence of large particles also affects the sensory quality. When the mass ratio of the composite filler deviates from the optimal ratio, the synergistic effect between the components is weakened. Although the individual performance is improved, the overall performance is still not ideal. Excessive phosphorylation and excessive use of phosphorylation reagents may lead to excessive cross-linking and make the gel brittle. At the same time, residual phosphates may affect food safety and taste. The use of high concentrations of acetic acid in the preparation of composite fillers may lead to partial degradation and gelation of chitosan molecular chains, affecting its uniform loading effect on the surface of microcrystalline cellulose. The use of too high a concentration of hydrochloric acid in the preparation of microcrystalline cellulose may lead to excessive hydrolysis of cellulose molecular chains and a decrease in crystallinity, affecting its reinforcing effect as a filler. When the phosphorylation reaction temperature is too low, the reaction is incomplete and the phosphorylation degree cannot reach the ideal level, affecting the cross-linking density and overall performance of the gel. Excessive temperature during gel preparation may lead to thermal degradation of konjac glucomannan molecules and destruction of the gel network structure. At the same time, high temperature may also affect the activity of chitosan, which leads to a comprehensive decline in gel performance.

[0080] Table 1 Performance of Konjac Gel of Examples 1 to 4 and Comparative Examples 1 to 10

[0081] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that any equivalent structural transformations made within the scope of the present invention using the contents of the present invention's description and drawings should be included within the scope of protection of the claims of the present invention.

Claims

1. A konjac gel food, characterized in that, The invention comprises the following raw materials in parts by weight: 50.0-100.0 parts of phosphorylated konjac glucomannan, 25.0-40.0 parts of chitosan / microcrystalline cellulose composite filler, 2.0-6.0 parts of calcium chloride, 1.0-4.0 parts of trisodium citrate, 1.0-5.0 parts of citric acid, 1.0-3.0 parts of sodium trimetaphosphate, 2.0-8.0 parts of carrageenan, 2.0-6.0 parts of sodium alginate, 1.0-3.0 parts of calcium lactate, and 200.0-400.0 parts of deionized water; The phosphorylated konjac glucomannan is obtained by reacting konjac glucomannan with phosphate, drying, and pulverizing; The chitosan / microcrystalline cellulose composite filler consists of microcrystalline cellulose and chitosan particles loaded on the surface of the microcrystalline cellulose, and achieves a synergistic effect of enhanced stability and improved brittleness through a multiple cross-linked network structure.

2. A konjac gel food as claimed in claim 1, characterized in that, The mass ratio of microcrystalline cellulose to chitosan of the chitosan / microcrystalline cellulose composite filler is (1.0-5.0): (0.5-2.0); The chitosan / microcrystalline cellulose composite filler has an average particle length of 16-50 μm and an average diameter of 2.0-5.0 μm.

3. A konjac gel food as claimed in claim 1, characterized in that, The mass ratio of the phosphorylated konjac glucomannan to the chitosan / microcrystalline cellulose composite filler is (1-4): (0.5-2); The weight ratio of the carrageenan to sodium alginate is (1-3): (1-2); The weight ratio of the calcium chloride to calcium lactate is (1-3): (0.5-1.5).

4. A konjac gel food as claimed in claim 1, characterized in that, The phosphates are sodium tripolyphosphate and sodium trimetaphosphate; The phosphorylation degree of the phosphorylated konjac glucomannan is 0.04-0.20; the intermolecular hydrogen bonding and ionic cross-linking effects are enhanced by the introduction of phosphate groups.

5. A konjac gel food as claimed in claim 1, characterized in that, The preparation method of the chitosan / microcrystalline cellulose composite filler is as follows: in parts by weight, 20.0-50.0 parts of chitosan are added to 500.0-1000.0 parts of an acetic acid aqueous solution with a mass concentration of 0.5%-1.0%, and mechanically stirred at a stirring rate of 300.0-500.0 rpm for 0.5-2.0 h at room temperature of 25.0±2.0°C until completely dissolved, to obtain a chitosan solution with a pH value of 3.8-4.2, and then 100.0 parts of microcrystalline cellulose are added to deionized water, and dispersed for 15.0-30.0 min using a high-speed shear disperser at a speed of 8000.0-12000.0 rpm to obtain a microcrystalline cellulose suspension, and then the pH value of the suspension is adjusted to 5.5-6.0 with a 0.1 mol / L sodium hydroxide aqueous solution, and the mixture is stirred at a speed of 1.0-3.0 under continuous mechanical stirring. The chitosan solution was slowly added to the microcrystalline cellulose suspension at a dropwise addition rate of 1 mL / min. During the addition, a pH meter was used to monitor the pH value of the system in real time and maintain it in the range of 5.8-6.

2. After the addition was completed, a high-speed shear dispersion treatment was performed at 6000.0-8000.0 rpm for 1.0-2.0 h to uniformly load the chitosan. The mixture was then centrifuged at a centrifugal rate of 3000.0-5000.0 rpm for 10.0-15.0 min. The supernatant was discarded and the mixture was repeatedly washed with deionized water 2-3 times until the filtrate was neutral. Finally, the precipitate was placed in a vacuum freeze dryer at -50.0--40.0°C for 12.0-24.0 h, crushed with a grinder, and passed through a 100-200 mesh standard sieve to obtain the target product.

6. A konjac gel food according to claim 1, characterized in that, The preparation method of the microcrystalline cellulose is as follows: 100.0 parts of cellulose raw material and 800.0~1200.0 parts of hydrochloric acid aqueous solution with a concentration of 2.5~4.0 mol / L are mixed uniformly in a reactor with a condensing device, and mechanically stirred at a stirring rate of 200.0~400.0 rpm in an atmosphere of normal pressure air, and heated at a heating rate of 5.0~10.0°C / min to a reaction temperature of 100.0~105.0°C for reflux hydrolysis reaction for 2.0~4.0 h. After the reaction, the system is cooled to room temperature of 25.0±2.0°C at a cooling rate of 3.0~5.0°C / min, and then a pore size of 0.45~0.65 is used. The solid product was separated by filtration through a microporous filter membrane with a μm diameter, and the solid product was repeatedly washed with deionized water 5 to 8 times until the pH value of the filtrate was 6.5 to 7.

5. The washed solid material was then placed in a vacuum drying oven at 60.0 to 80.0°C for 4.0 to 8.0 hours, and finally processed in a high-speed shear mill at a speed of 10000.0 to 15000.0 rpm for 30.0 to 60.0 minutes to obtain microcrystalline cellulose.

7. A konjac gel food according to claim 1, characterized in that, The preparation method of the phosphorylated konjac glucomannan comprises the following steps: dispersing 100.0 parts of konjac glucomannan in 500.0-800.0 parts of deionized water in parts by weight, mechanically stirring the mixture at a stirring rate of 300.0-500.0 rpm in an atmosphere of normal pressure air, heating the mixture to a reaction temperature of 50.0-70.0°C at a heating rate of 3.0-5.0°C / min for 1.0-2.0 h to obtain a uniform colloidal solution, then sequentially adding 15.0-25.0 parts of sodium tripolyphosphate and 8.0-15.0 parts of sodium trimetaphosphate, adjusting the pH value of the system to 6.8-7.2 with a 0.1 mol / L sodium hydroxide aqueous solution, then heating the reaction system to 90.0-95.0°C at a heating rate of 5.0-8.0°C / min, reacting the mixture at a stirring rate of 200.0-400.0 rpm for 3.0-5.0 h under the temperature condition, and h, and a pH meter was used to monitor and maintain the pH value stable during the reaction. After the reaction, the system was cooled to room temperature (25.0±2.0°C), and then an ethanol aqueous solution with a volume fraction of 85% to 95% was added for alcohol precipitation separation. The precipitate was filtered through a microporous filter membrane with a pore size of 0.45 to 0.65 μm, and then washed with deionized water 3 to 5 times until the filtrate was neutral. Finally, the product was placed in a vacuum drying oven at 45.0 to 60.0°C for 8.0 to 12.0 h, crushed with a grinder, and passed through a 120-200 mesh standard sieve to obtain a phosphorylated konjac glucomannan product.

8. A method for preparing a konjac gel food according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1: Accurately weigh the raw materials in parts by weight, add the phosphorylated konjac glucomannan to deionized water, and mechanically stir at 75-85° C. for 1-2 hours to obtain a uniform and transparent colloidal solution; S2: The colloidal solution temperature is adjusted to 60-65°C, chitosan / microcrystalline cellulose composite filler is added, and high-speed shear dispersion technology is used for 10-30 minutes at a speed of 4000-6000 rpm to ensure that the filler is evenly dispersed. Carrageenan and sodium alginate are then added in sequence and stirred at high speed for 10-20 minutes until completely dissolved; S3: The system temperature is adjusted to 50-55° C., and calcium chloride, calcium lactate, citric acid, trisodium citrate, and sodium trimetaphosphate are added in sequence. After each component is added, stirring is performed for 5-10 minutes, and the final pH value is adjusted to 6.5-7.0 with citric acid to obtain a konjac gel precursor. The precursor is then placed in a vacuum environment for degassing for 10-20 minutes at a vacuum degree of -0.08 to -0.10 MPa to remove bubbles in the system. S4: pouring the degassed precursor into a prefabricated mold, allowing it to stand at room temperature for 25 to 35 minutes for preliminary gelation, then placing the initial gel product in a 2 to 6° C. refrigerated environment for curing for 2 to 4 hours, demolding and cutting into predetermined sizes as needed to obtain the konjac gel food.

9. The method for preparing the konjac gel food according to claim 8, wherein During the preparation process, the orderly construction of the layered gel network is achieved by temperature gradient control, wherein the high temperature of 75-85°C in step S1 promotes the full swelling of the phosphorylated konjac glucomannan, the medium temperature of 60-65°C in step S2 ensures the uniform dispersion of the composite filler and the dissolution of the polysaccharide component, the low temperature of 50-55°C in step S3 avoids the thermal inactivation of the cross-linking agent, and the temperature gradient from room temperature to refrigeration in step S4 achieves the gradual solidification and stabilization of the gel network.

10. An application of the konjac gel food according to any one of claims 1 to 7, characterized in that: Application in foods that simulate the taste of animal cartilage tissue.

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