Preparation method of efficient enzyme catalyst for low-sugar food
By synergistically designing a modified tea polyphenol-chitosan composite carrier with 2-hydroxy-4-methoxyacetophenone, the problems of enzyme catalyst activity decay and stability in low-sugar food systems were solved, achieving efficient and stable enzyme catalysis, which is suitable for the food industry.
Patent Information
- Application Number
- CN202511520478.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-23
- Publication Date
- 2026-03-06
AI Technical Summary
In low-sugar food systems, problems such as enzyme catalyst activity decay, unstable fixation, and insufficient raw material safety exist. In particular, under low ionic strength and polar environment changes, the hydration layer on the surface of enzyme molecules is unstable, leading to reduced catalytic activity, slower reaction rate, and shortened cycle life.
A modified tea polyphenol-chitosan composite carrier was used. Tea polyphenols and chitosan were covalently grafted with C–N and C–O bonds through laccase catalysis. The composite structure was modified by lactobionol glycosylation and vitamin C reduction amination to construct a stable multi-site cross-linked composite structure. At the same time, 2-hydroxy-4-methoxyacetophenone was introduced as a food-grade co-catalytic small molecule to form a mild and stable catalytic system.
This method achieves high activity and good stability of the catalyst in a low-sugar environment, improves the binding strength and interfacial uniformity of enzyme molecules, and enhances the dispersibility and stability of the enzyme catalyst, making it suitable for industrial applications in the food industry.
Smart Images
Figure CN121610480A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of food chemistry and biocatalysis technology, specifically relating to a high-efficiency enzyme catalyst for low-sugar foods and its preparation method. Background Technology
[0002] In recent years, with the popularization of sugar substitutes, sugar-controlled diets, and functional foods, the application of enzyme catalysis in low-sugar systems has become increasingly widespread, such as in processes like glucose isomerization, polysaccharide degradation, oligosaccharide synthesis, and sweet peptide preparation. However, in low-sugar food systems, due to the low content of soluble sugars, the ionic strength and polar environment of the system change, leading to instability of the hydration layer on the enzyme molecule surface and a decrease in conformational flexibility. This, in turn, results in reduced catalytic activity, slower reaction rates, and shorter cycle life.
[0003] Currently, commonly used immobilization carriers mainly include natural polysaccharides and plant polyphenols. Although these materials have good biocompatibility, the lack of controllable active sites in their molecular structure leads to weak interactions with enzyme molecules, making them prone to desorption or denaturation in low-sugar or low-ionic-strength environments. Furthermore, traditional chemical modification methods suffer from problems such as demanding reaction conditions, difficulty in removing residual reagents, and food safety risks.
[0004] In low-sugar food systems, small organic molecules are often used as cocatalysts to improve substrate recognition or conversion rates. However, common small molecules such as levulinic acid, citric acid, or amino acid derivatives often have defects such as poor reaction specificity, insufficient stability, or flavor interference, making it difficult to maintain their activity in food-grade systems for a long time.
[0005] Therefore, developing a composite carrier that achieves multi-site synergistic modification through green enzyme catalysis and introducing simple and food-safe organic small molecule co-catalytic components to construct an enzyme catalytic system that remains stable and efficient in a low-sugar environment has become an urgent technical problem to be solved in this field. Summary of the Invention
[0006] To overcome the problems of enzyme catalyst activity decay, unstable fixation, and insufficient raw material safety in existing low-sugar food systems, the present invention aims to provide a high-efficiency enzyme catalyst for low-sugar foods and its preparation method, achieving high activity and good stability of the catalyst in low-sugar systems. The catalyst of this invention consists of a modified tea polyphenol-chitosan composite carrier, 2-hydroxy-4-methoxyacetophenone, stabilizers, complexing aids, dispersants, pH buffers, and deionized water. The modified tea polyphenol-chitosan composite carrier uses chitosan as a matrix, and is prepared by covalent grafting of tea polyphenols and chitosan through C–N and C–O bonds via laccase catalysis, followed by lactobionyl lactone glycosylation and vitamin C reductive amination modification, thereby obtaining a structurally stable and interface-uniform composite carrier. This invention achieves a synergistic distribution of hydrophilic and hydrophobic regions on the carrier surface by introducing controllable glycosylation and reductive amination reactions into the composite carrier structure; and constructs a mild and stable catalytic system by selecting structurally simple 2-hydroxy-4-methoxyacetophenone as a food-grade co-catalytic small molecule. The catalyst of this invention has a stable structure, high food safety, excellent dispersibility and stability in low-sugar environments, and a mild and controllable preparation process, making it suitable for industrial food applications.
[0007] The objective of this invention can be achieved through the following technical solutions: A high-efficiency enzyme catalyst for low-sugar foods comprises the following raw materials in parts by weight: 60-80 parts of modified tea polyphenol-chitosan composite carrier; 10-25 parts of 2-hydroxy-4-methoxyacetophenone; 2-5 parts of stabilizer; 1-3 parts of complexing agent; 0.5-1.5 parts of dispersant; 1-2 parts of pH buffer; and 100-150 parts of deionized water. The modified tea polyphenol-chitosan composite carrier is a composite polymer carrier based on chitosan, which undergoes C-N and C-O bond covalent grafting between tea polyphenol molecules and chitosan via laccase catalysis, followed by lactobionyl lactone glycosylation and vitamin C reducing amination modification. The 2-hydroxy-4-methoxyacetophenone is an aromatic ketone compound composed of a benzene ring, hydroxyl group, methoxy group, and acetyl side chain.
[0008] Optionally, the modified tea polyphenol-chitosan composite carrier comprises the following raw materials in parts by weight: 40-60 parts tea polyphenols; 100 parts chitosan; 10-25 parts lactobionolide; 1-2 parts laccase; 0.05-0.10 parts vitamin C; and 100-150 parts deionized water.
[0009] Optionally, the preparation method of the modified tea polyphenol-chitosan composite carrier includes the following steps: (1) Dissolve chitosan to form a reaction system, add tea polyphenols, lactobionolide and laccase, and carry out enzyme-catalyzed grafting reaction; (2) Continue the glycosylation reaction in the reaction system to open the ring of lactobionolone and bind to the carrier; (3) Add vitamin C to the reaction system to carry out a reducing amination reaction and obtain the modified composite carrier; (4) The obtained reaction product was purified and dried to obtain the modified tea polyphenol-chitosan composite carrier.
[0010] Optionally, the enzyme-catalyzed grafting reaction conditions in step (1) are pH 6.6–6.8, temperature 25–30°C, and reaction time 2–3 hours.
[0011] Optionally, the glycosylation reaction conditions in step (2) are a temperature of 25–30 °C and a reaction time of 1 hour.
[0012] Optionally, the reaction conditions in step (3) are to react at 25-30°C for 0.5-1 hour after adding vitamin C.
[0013] Optionally, the stabilizer is a mixture of glycerol and sorbitol in a mass ratio of 1:1; the complexing agent is a mixture of calcium lactate and sodium citrate in a mass ratio of 1:1; the dispersant is a mixture of polyvinylpyrrolidone and Tween-80 in a mass ratio of 2:1; and the pH buffer is a mixture of sodium dihydrogen phosphate and disodium hydrogen phosphate in a mass ratio of 1:1.
[0014] Optionally, a method for preparing a high-efficiency enzyme catalyst for low-sugar foods includes the following steps: S1, a reaction system is formed by mixing modified tea polyphenol-chitosan composite carrier, 2-hydroxy-4-methoxyacetophenone, stabilizer, complexing aid, dispersant, pH buffer and deionized water; S2, the reaction system is stirred to ensure that the components are fully combined and dispersed; S3. The reaction system is dried to obtain a high-efficiency enzyme catalyst for low-sugar foods.
[0015] Optionally, the reaction conditions for step S1 are mixing at room temperature and stirring continuously for 10 to 20 minutes; the reaction conditions for step S2 are stirring at 25 to 30°C for 2 to 3 hours; and the reaction conditions for step S3 are drying by spray drying.
[0016] The beneficial effects of this invention are: This invention introduces laccase-catalyzed grafting to achieve dual-site covalent bonding of C–N and C–O bonds between tea polyphenol molecules and chitosan segments under mild conditions, forming a stable multi-site cross-linked composite structure. This improves the structural stability and interfacial bonding strength of the carrier at the molecular level. Lactobionolide glycosylation modification introduces a glycosyl substitution layer on the carrier surface, forming an ordered hydrophilic-hydrophobic partition structure. This provides a uniform and controllable interfacial environment for subsequent enzyme binding, solving the problems of single and unevenly distributed interfacial energy in traditional carriers. A vitamin C reductive amination reaction is introduced in the later stage of modification, transforming the dynamic Schiff base structure generated by the phenolamine reaction into a stable C–N secondary amine bond, significantly improving the chemical stability of the modified layer and avoiding the defects of reversible bonding and easy dissociation after long-term use in traditional chemical cross-linking systems. This invention is the first to introduce 2-hydroxy-4-methoxyacetophenone into a low-sugar food enzyme catalytic system. This small molecule has a simple structure, high stability, and good molecular construction compatibility, providing a novel co-component design concept for the field and expanding the compositional range and molecular regulation pathways of enzyme catalyst materials. Attached Figure Description
[0017] The invention will now be further described with reference to the accompanying drawings.
[0018] Figure 1 A comparison of the infrared spectra of the tea polyphenol-chitosan composite carrier and the modified tea polyphenol-chitosan composite carrier; Figure 2 A comparison chart of the stability test results for samples with different formulation ratios after repeated use. Detailed Implementation
[0019] The present invention will be further described below with reference to specific embodiments. However, the present invention is not limited to the following embodiments. Equivalent adjustments made without departing from the spirit and essence of the present invention should also be considered to fall within the protection scope of the present invention.
[0020] Example 1 The purpose of this embodiment is to use an upper limit value for the component ratio in order to verify the structural stability and component compatibility of the catalyst of the present invention under high support content conditions.
[0021] S1. Weigh 100 parts of chitosan and dissolve it in 150 parts of deionized water. Adjust the pH to 6.7, add 60 parts of tea polyphenols, 25 parts of lactobionol, and 2 parts of laccase. Stir and react at 25°C for 3 hours to carry out the enzymatic grafting reaction. Then maintain the temperature at 25°C and continue the reaction for 1 hour to allow lactobionol to open its ring and complete the glycosylation reaction. Finally, add 0.10 parts of vitamin C and react at 30°C for 1 hour to carry out the reductive amination reaction. The resulting reaction solution is dialyzed to remove small molecule impurities and then freeze-dried to obtain the modified tea polyphenol-chitosan composite carrier. S2, add 80 parts of the obtained modified tea polyphenol-chitosan composite carrier, 25 parts of 2-hydroxy-4-methoxyacetophenone, 5 parts of stabilizer, 3 parts of complexing agent, 1.5 parts of dispersant, and 2 parts of pH buffer to 150 parts of deionized water, and stir at room temperature for 20 minutes to form a homogeneous reaction system. S3, the system was stirred at 30°C for 2 hours to ensure that the components were fully dispersed; then spray-dried to obtain a light brown powder of high-efficiency enzyme catalyst for low-sugar food.
[0022] Example 2 The purpose of this embodiment is to use a lower limit value for the component ratio in order to examine the composite stability and dispersion uniformity of the catalyst of the present invention under conditions of low support content.
[0023] S1. Weigh 100 parts of chitosan and dissolve it in 100 parts of deionized water. Adjust the pH to 6.6, add 40 parts of tea polyphenols, 10 parts of lactobionolide, and 1 part of laccase. Stir and react at 25°C for 2 hours. Maintain the same temperature and continue the reaction for 1 hour to complete the glycosylation process. Add 0.05 parts of vitamin C and react at 25°C for 0.5 hours to carry out the reductive amination reaction. After the reaction is completed, dialysis purification and freeze-drying are performed to obtain the modified tea polyphenol-chitosan composite carrier. S2, add 60 parts of the obtained carrier, 10 parts of 2-hydroxy-4-methoxyacetophenone, 2 parts of stabilizer, 1 part of complexing agent, 0.5 parts of dispersant, and 1 part of pH buffer to 100 parts of deionized water, and stir at room temperature for 10 minutes to form a reaction system. S3 was stirred at 25°C for 2 hours, and then spray-dried to obtain a light brown powdered enzyme catalyst.
[0024] Example 3 The purpose of this embodiment is to use an intermediate value in the component ratio to obtain a comprehensive formulation with optimal performance and to verify the reproducibility of the preparation of the catalyst of the present invention under standard conditions.
[0025] S1. Weigh 100 parts of chitosan and dissolve it in 120 parts of deionized water. Adjust the pH to 6.7, add 50 parts of tea polyphenols, 15 parts of lactobionolide, and 1.5 parts of laccase. Stir and react at 27°C for 2.5 hours to complete the enzyme-catalyzed grafting reaction. Continue to react at the same temperature for 1 hour to allow lactobionolide to fully open the ring and glycosylate. Add 0.08 parts of vitamin C and react at 27°C for 0.8 hours for reductive amination. The resulting product is purified by dialysis and freeze-dried to obtain the modified tea polyphenol-chitosan composite carrier. Figure 1 The results showed significant differences between the tea polyphenol-chitosan composite carrier and the modified tea polyphenol-chitosan composite carrier in several key regions. The unmodified sample showed differences at 3400 cm⁻¹. -1A broad and strong O–H / N–H stretching band appears at 1655 cm⁻¹. After modification, this peak slightly red-shifts and narrows, indicating that the hydrogen bond network has been reconstructed. -1 The Amide I peak at 1535 cm⁻¹ is significantly enhanced, indicating that C=O and N–H are involved in amide bond formation; -1 The appearance of a new AmideII absorption peak at 1295 cm⁻¹ provides direct evidence of the successful laccase grafting and reductive amination reaction. -1 C–N stretching peaks and 1142–1072 cm⁻¹ -1 The C–O–C / C–O regions were significantly enhanced, reflecting the binding of glycosylation with the polysaccharide backbone. Overall, the modified tea polyphenol-chitosan composite carrier spectrum showed obvious new peaks, enhanced absorption intensity, and clear structural features, confirming that the tea polyphenol-chitosan composite carrier formed a stable multi-site covalent structure after synergistic modification. S2, add 70 parts of the above carrier, 18 parts of 2-hydroxy-4-methoxyacetophenone, 3.5 parts of stabilizer, 2 parts of complexing agent, 1 part of dispersant, and 1.5 parts of pH buffer to 120 parts of deionized water, stir at room temperature for 15 minutes to form a homogeneous reaction system. S3 was stirred and reacted at 28°C for 2.5 hours, and then dried by spray drying to obtain a light yellow powder of high-efficiency enzyme catalyst for low-sugar food.
[0026] Comparative Example 1 The purpose of this comparative example is to verify the effect of using only laccase catalytic modification without glycosylation and reductive amination on the catalyst structure and stability.
[0027] S1. Weigh 100 parts of chitosan and dissolve it in 120 parts of deionized water. Adjust the pH to 6.7, add 50 parts of tea polyphenols and 1.5 parts of laccase, and stir at 27°C for 2.5 hours to complete the enzyme-catalyzed grafting reaction. Do not add lactobionol or vitamin C. The resulting product is purified by dialysis and freeze-dried to obtain a single laccase-modified tea polyphenol-chitosan composite carrier. S2, add 70 parts of the above carrier, 18 parts of 2-hydroxy-4-methoxyacetophenone, 3.5 parts of stabilizer, 2 parts of complexing agent, 1 part of dispersant, and 1.5 parts of pH buffer to 120 parts of deionized water, stir at room temperature for 15 minutes to form a homogeneous reaction system. S3 was stirred at 28°C for 2.5 hours and then dried by spray drying to obtain a light brown powdered enzyme catalyst.
[0028] Comparative Example 2 The purpose of this comparative example is to verify the changes in catalyst structure and performance when only glycosylation modification is performed without laccase grafting and reductive amination.
[0029] S1, 100 parts of chitosan were weighed and dissolved in 120 parts of deionized water. The pH was adjusted to 6.7, and 50 parts of tea polyphenols and 15 parts of lactobionol were added. The mixture was stirred at 27°C for 3 hours to allow lactobionol to open its ring and undergo a glycosylation reaction with the tea polyphenol-chitosan system. Laccase and vitamin C were not added. The resulting reaction solution was purified by dialysis and freeze-dried to obtain a single glycosylated modified tea polyphenol-chitosan composite carrier. S2, add 70 parts of the above-mentioned carrier, 18 parts of 2-hydroxy-4-methoxyacetophenone, 3.5 parts of stabilizer, 2 parts of complexing agent, 1 part of dispersant, and 1.5 parts of pH buffer to 120 parts of deionized water, and stir at room temperature for 15 minutes to form a reaction system. S3 was stirred at 28°C for 2.5 hours and then dried by spray drying to obtain a light yellow powdered enzyme catalyst.
[0030] Comparative Example 3 The purpose of this comparative example is to verify the changes in catalyst structural uniformity and stability without the addition of the small organic molecule 2-hydroxy-4-methoxyacetophenone.
[0031] S1. Weigh 100 parts of chitosan and dissolve it in 120 parts of deionized water. Adjust the pH to 6.7, add 50 parts of tea polyphenols, 15 parts of lactobionolide, and 1.5 parts of laccase. Stir and react at 27°C for 2.5 hours to carry out the enzyme-catalyzed grafting reaction. Continue to react at the same temperature for 1 hour to allow lactobionolide to fully open the ring and glycosylate. Add 0.08 parts of vitamin C and react at 27°C for 0.8 hours to carry out reductive amination. The resulting product is purified by dialysis and freeze-dried to obtain the modified tea polyphenol-chitosan composite carrier. S2, add 70 parts of the above carrier, 3.5 parts of stabilizer, 2 parts of complexing agent, 1 part of dispersant, and 1.5 parts of pH buffer to 120 parts of deionized water, stir at room temperature for 15 minutes to form a homogeneous reaction system; S3 was stirred at 28°C for 2.5 hours and then dried by spray drying to obtain a light yellow powdered control enzyme catalyst.
[0032] Performance testing 1. Enzyme loading and activity recovery rate test This test was used to evaluate the enzyme loading capacity and initial catalytic activity retention of different samples during immobilization. Each sample catalyst was dispersed in a phosphate buffer solution at pH 6.8 to prepare a homogeneous suspension. Food-grade β-galactosidase solution was added, and the suspension was gently shaken at a constant temperature of 25°C to ensure thorough binding of the enzyme molecules to the carrier. After immobilization, the supernatant was separated by centrifugation, and the content of unbound enzyme was determined using a protein quantification method. The obtained data were used to calculate the immobilization efficiency of each sample. Subsequently, equal volumes of immobilized catalyst were taken and their initial catalytic activity was measured in the same substrate system. The changes in absorbance of the product were recorded colorimetrically, and the initial activity of each sample was calculated. The results were used to compare the immobilization capacity and enzyme activity retention levels between the examples and comparative examples.
[0033] 2. Low-sugar environment adaptability test This test was used to verify the ability of different catalysts to maintain activity in a low-sugar system. Phosphate buffer solutions containing 0%, 1%, 3%, and 5% sucrose were prepared as reaction media, and the same amount of immobilized enzyme catalyst was added to each system. The reaction was terminated after a certain time at a constant temperature of 37°C, and the absorbance of the product in each system was measured and the relative activity was calculated. By using the activity of the sugar-free system as a benchmark, the activity retention at each sugar concentration can be obtained. The results reflect the protective effect of different support structures on the enzyme molecular conformation under low-sugar conditions.
[0034] 3. Cyclic Use Stability Test This test was used to investigate the activity retention performance of immobilized catalysts during multiple reuses. Each sample's immobilized enzyme underwent an initial reaction in a standard substrate system, followed by separation and recovery. Residual substrate was washed away, and the enzyme was reintroduced into a fresh system for further reaction, repeated ten times. Catalytic activity was measured after each reaction, and the activity of the initial reaction was used as a reference to calculate the retention rate in subsequent reactions. By plotting the trend of cycle number versus activity retention rate, the reusability of different samples can be evaluated. This test can visually reflect the impact of support modification methods on enzyme binding strength and structural stability.
[0035] 4. Storage stability and accelerated stability testing This test was used to evaluate the catalyst's activity retention under different storage conditions. The samples were divided into two groups: one group was stored long-term at 4°C in the dark to simulate the actual food processing and storage environment; the other group underwent accelerated aging at 45°C and 75% relative humidity to assess its stability under high temperature and humidity conditions. Samples were taken at different time points, reconstituted, and their catalytic activity was measured, recording the activity retention over time. By comparing the differences in activity decay between the examples and comparative examples under long-term and high-temperature conditions, the contribution of the support structure and the synergistic effect of the organic small molecules to the long-term stability of the catalyst can be determined.
[0036] Table 1 Results of enzyme loading and activity recovery rate tests Table 2 Results of Low-Sugar Environment Adaptability Test Table 3 Results of Cyclic Use Stability Test Table 4. Results of Storage Stability and Accelerated Stability Tests As shown in Table 1, the immobilization loading and efficiency of the three examples were significantly higher than those of the comparative examples, indicating that the carrier modified at multiple sites through laccase catalysis, glycosylation, and reductive amination has a higher enzyme binding capacity. Specifically, Example 3 achieved an immobilization efficiency of 96.5% and an initial enzyme activity retention rate of 102.6%, demonstrating that its structure achieved optimal enzyme immobilization while maintaining a balance between hydrophilicity and hydrophobicity. In contrast, the immobilization efficiencies of Comparative Examples 1 and 2 were only 77.4% and 74.1%, respectively, reflecting that single modification cannot provide sufficient binding sites and interfacial stability.
[0037] As shown in Table 2, the low-sugar environment adaptability test results indicate that the sample from the examples maintained high activity in a 1%–5% sucrose system. In particular, Example 3 showed an activity retention rate of up to 95% at 5% sugar content, which is much higher than the 60%–70% of the comparative examples. This demonstrates that the glycosylated and reductively amination-modified composite carrier can maintain the spatial conformational stability of enzyme molecules in a low-sugar environment, thereby effectively avoiding inactivation caused by a decrease in osmotic pressure.
[0038] As can be seen from the stability results of cyclic use in Table 3, Figure 2 The catalyst in the intermediate examples retained over 80% of its activity after 10 repeated uses, while the retention rate in Example 3 reached as high as 91%, significantly better than the 60%–68% of the comparative examples. This result demonstrates that the synergistic structure of the modified tea polyphenol-chitosan composite carrier and 2-hydroxy-4-methoxyacetophenone enhances the chemical binding and physical intercalation between the enzyme and the carrier, thereby effectively delaying the desorption and inactivation of the immobilized enzyme during the reaction process.
[0039] As shown in Table 4, the storage stability and accelerated stability test results of Example 3 indicate that the activity retention rate was 93% after 12 months of storage at 4℃, and still 87% after 30 days of accelerated storage at 45℃ / 75%RH, with a comprehensive stability score of 90.0, significantly better than the 57.5–65.0 of the comparative examples. This demonstrates that the multi-site modified structure and organic small molecule synergistic design employed in this invention can significantly improve the chemical stability and environmental tolerance of the support.
[0040] Based on the combined results of the four performance parameters, Example 3 showed the best performance in terms of immobilization efficiency, low sugar adaptability, cycle stability, and storage durability, which fully verified the innovation and rationality of the present invention in terms of structural design and reaction control.
Claims
1. A high-efficiency enzyme catalyst for low-sugar food, characterized by comprising a cellulase and a protease. The low-sugar food enzyme catalyst comprises the following raw materials in parts by weight: a modified tea polyphenol-chitosan composite carrier 60-80 parts; 2-hydroxy-4-methoxy acetophenone 10-25 parts; a stabilizer 2-5 parts; a complexing aid 1-3 parts; a dispersing agent 0.5-1.5 parts; a pH buffer 1-2 parts; and deionized water 100-150 parts; wherein the modified tea polyphenol-chitosan composite carrier is a composite polymer carrier which is modified by lactobionolactone glycosylation and vitamin C reductive amination, and is grafted with tea polyphenol molecules and chitosan through laccase catalysis to form C-N and C-O bonds; and the 2-hydroxy-4-methoxy acetophenone is an aromatic ketone compound composed of a benzene ring, a hydroxyl group, a methoxy group and an acetyl side chain.
2. The high-efficiency enzyme catalyst for low-sugar food according to claim 1, characterized by, The modified tea polyphenol-chitosan composite carrier comprises the following raw materials in parts by weight: tea polyphenol 40-60 parts; chitosan 100 parts; lactobionolactone 10-25 parts; laccase 1-2 parts; vitamin C 0.05-0.10 parts; and deionized water 100-150 parts.
3. The high-efficiency enzyme catalyst for low-sugar food according to any one of claims 1 or 2, characterized by, The preparation method of the modified tea polyphenol-chitosan composite carrier comprises the following steps: (1) dissolving chitosan to form a reaction system, adding tea polyphenol, lactobionolactone and laccase, and performing enzyme catalysis grafting reaction; (2) continuing to perform glycosylation reaction in the reaction system to open the ring of lactobionolactone and combine with the carrier; (3) adding vitamin C to the reaction system to perform reductive amination reaction to obtain the modified composite carrier; (4) purifying and drying the obtained reaction product to obtain the modified tea polyphenol-chitosan composite carrier.
4. The high-efficiency enzyme catalyst for low-sugar food according to claim 3, characterized by, The enzyme catalysis grafting reaction condition of step (1) is pH 6.6-6.8, temperature 25-30 DEG C, and reaction time 2-3 hours.
5. The high-efficiency enzyme catalyst for low-sugar food according to claim 3, characterized by, The glycosylation reaction condition of step (2) is temperature 25-30 DEG C and reaction time 1 hour.
6. The high-efficiency enzyme catalyst for low-sugar food according to claim 3, characterized by, The reaction condition of step (3) is to react for 0.5-1 hour at 25-30 DEG C after adding vitamin C.
7. The high-efficiency enzyme catalyst for low-sugar food according to claim 1, characterized by, The stabilizer is a mixture of glycerol and sorbitol in a mass ratio of 1:1; the complexing aid is a mixture of calcium lactate and sodium citrate in a mass ratio of 1:1; the dispersing agent is a mixture of polyvinylpyrrolidone and Tween-80 in a mass ratio of 2:1; and the pH buffer is a mixture of sodium dihydrogen phosphate and disodium hydrogen phosphate in a mass ratio of 1:
1.
8. A method for producing a high-performance enzyme catalyst for low-sugar food, the high-performance enzyme catalyst for low-sugar food being as described in any one of claims 1 to 7, characterized by, The method comprises the following steps: S1, mixing the modified tea polyphenol-chitosan composite carrier, 2-hydroxy-4-methoxy acetophenone, stabilizer, complexing aid, dispersing agent, pH buffer and deionized water to form a reaction system; S2, stirring the reaction system to fully compound and disperse the components; S3, drying the reaction system to obtain the low-sugar food high-efficiency enzyme catalyst.
9. The method for preparing a high-efficiency enzyme catalyst for a low-sugar food according to claim 8, characterized by, The reaction condition of step S1 is to mix at room temperature and continuously stir for 10-20 minutes; the reaction condition of step S2 is to stir at 25-30 DEG C for 2-3 hours; and the reaction condition of step S3 is to perform drying treatment by spray drying.