Chitosan-rhodotorula composite microparticle for prolonging life of fresh fish fillet and application of chitosan-rhodotorula composite microparticle
Complex microparticles prepared by combining chitosan with red yeast adhere to the surface of fresh fish fillets to form a protective film, inhibit microbial growth, solve the problem of perishable fresh fish fillets, significantly extend their freshness and shelf life, and improve food safety.
Patent Information
- Application Number
- CN202510441147.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-09
- Publication Date
- 2025-05-16
AI Technical Summary
As perishable food, fresh fish fillets are susceptible to microbial contamination and deterioration during storage and transportation. Traditional preservation methods cannot completely prevent quality declines, resulting in a large number of fish losing their commercial value before they reach the market.
A chitosan-Red yeast complex microparticles were developed. By combining red yeast with chitosan, it was prepared into microparticles with biological activity and relief functions, attached to the surface of fresh fish fillets, forming a protective film, and inhibiting the growth of harmful microorganisms.
It significantly extends the freshness and shelf life of fresh fish fillets, reduces the growth of microbial numbers, maintains sensory quality, and improves the safety and quality of food.
Smart Images
Figure CN119999759A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of food preservation, in particular to a chitosan-red yeast composite microparticle for prolonging the life of fresh fish slices and an application thereof. Background Art
[0002] With the increase of global population and the improvement of living standards, people's demand for fresh food is increasing, especially for high-quality and safe aquatic products. For example, the demand for fresh fish fillets has increased significantly. As one of the world's largest aquaculture countries, China's domestic market demand for fresh fish fillets is also increasing year by year, especially in first-tier cities and coastal areas, where consumers prefer to buy fresh rather than frozen seafood.
[0003] As a perishable food, fresh fish fillets are easily contaminated by microorganisms and deteriorate during storage and transportation. Although traditional preservation methods such as low-temperature refrigeration can delay spoilage, they cannot completely prevent quality degradation. According to estimates from aquatic economics, about 30% of the world's fish catches lose their commercial value before reaching the market due to improper storage, causing huge economic losses. Therefore, the development of new and efficient preservation technologies is crucial to maintaining the freshness of fish.
[0004] In recent years, natural polysaccharides such as chitosan have been widely used in food preservation due to their good biocompatibility and antibacterial properties. However, the use of chitosan alone has some limitations, such as its limited antibacterial effect and duration of action. Summary of the invention
[0005] The purpose of the present invention is to develop a composite microparticle composed of chitosan and red yeast to solve the above technical problems.
[0006] To achieve the above object, the present invention adopts the following technical solution: In a first aspect, the present invention provides a chitosan-red yeast composite microparticle for extending the life of fresh fish fillets, which is made by mixing chitosan and red yeast and then solidifying, wherein the red yeast is encapsulated in the chitosan, and the diameter size of the chitosan-red yeast composite microparticle is distributed between 50μm and 100μm.
[0007] The present invention combines red yeast with chitosan to prepare microparticles with biological activity and mitigation function, which can fully utilize the advantages of the two components: chitosan mainly provides a physical barrier function, and red yeast provides its own antibacterial activity and other beneficial properties. These microparticles can effectively adhere to the surface of fresh fish slices to form a protective film, inhibit the growth of harmful microorganisms, and reduce oxidation reactions, thereby significantly extending the freshness and shelf life of fresh fish slices.
[0008] Furthermore, the deacetylation degree of the chitosan is not less than 90%.
[0009] Furthermore, the red yeast is marine red yeast.
[0010] Furthermore, the diameter of the chitosan-red yeast composite microparticles is distributed between 50 μm and 100 μm.
[0011] In a second aspect, the present invention provides a method for preparing the chitosan-red yeast composite microparticles, comprising the following steps: S1, mixing red yeast fermentation broth and chitosan solution in equal volume ratio to obtain a mixed solution; S2. Adding 1.8% to 2% by volume of glutaraldehyde into the mixed solution for solidification to obtain the chitosan-red yeast composite microparticles.
[0012] Furthermore, the concentration of the red yeast fermentation broth is 1.5×10 10 ~1.8×10 10 cfu / mL.
[0013] Furthermore, the chitosan solution has a concentration of 8-12 g / L, and the chitosan solution uses glacial acetic acid with a volume concentration of 0.9%-1.1% as a solvent.
[0014] Furthermore, the curing condition is standing at 4-5°C for 3-4 hours.
[0015] In a third aspect, the present invention provides the use of the chitosan-red yeast composite microparticles in extending the life of fresh fish fillets. The chitosan-red yeast composite microparticles do not contain additional antioxidants, enzyme inhibitors or other additives, and only rely on the characteristics of chitosan and red yeast to achieve the preservation effect.
[0016] In a fourth aspect, the present invention provides a method for extending the life of fresh fish fillets, wherein the fresh fish fillets are immersed in the suspension of the chitosan-red yeast composite microparticles for 10 to 20 minutes, the fresh fish fillets are taken out to remove excess water, a stable film layer is formed on the surface of the fresh fish fillets, and then the fresh fish fillets are stored at 4 to 8° C. The growth of the number of microorganisms in the treated fresh fish fillets is significantly slowed down under low-temperature storage conditions, the sensory quality can be maintained for a longer time, and the life of the fresh fish fillets is effectively extended.
[0017] Further, excess water is removed by draining, low temperature drying or vacuum drying.
[0018] The present invention has the following beneficial effects: The growth of the number of microorganisms in the fresh fish slices treated with the chitosan-red yeast composite microparticles of the present invention is significantly slowed down under low-temperature storage conditions, and the sensory quality can be maintained for a longer time, thereby effectively extending the life of the fresh fish slices and improving the safety and quality of the food.
[0019] The invention provides a novel and efficient fresh fish fillet preservation technology with broad application prospects. It not only simplifies the operation process and improves food safety, but also provides a new solution for the aquatic product industry. BRIEF DESCRIPTION OF THE DRAWINGS
[0020] Figure 1 The figure is a statistical chart of the total colony counts of five groups of samples.
[0021] Figure 2 These are photos of colonies of five groups of samples sampled at 72 hours. DETAILED DESCRIPTION
[0022] The present invention is described in detail below in conjunction with the accompanying drawings and specific examples, but should not be construed as limiting the present invention. Unless otherwise specified, the technical means used in the following examples are conventional means well known to those skilled in the art, and the materials, reagents, etc. used in the following examples, unless otherwise specified, can be obtained from commercial sources.
[0023] The red yeast involved below is marine red yeast ( Rhodotorula mucilagenosa ), lyophilized powder was purchased from Guangzhou Xinhai Lisheng Biotechnology Co., Ltd., China, and deposited in the General Microbiological Center of China Microbiological Culture Collection Administration, with the strain preservation number CGMCC NO.18634. Chitosan was 200 cps chitosan (purity ≥75%), purchased from Sigma, USA, CAS number #: 9012-76-4.
[0024] Example 1: A chitosan-red yeast composite microparticle The chitosan-red yeast composite microparticles of this embodiment are prepared by the following steps: (1) Preparation of chitosan solution First, weigh 1g of chitosan and dissolve it in 100ml of 1% (v / v) glacial acetic acid aqueous solution, heat it to 45°C, use a magnetic stirrer until the chitosan is completely dissolved, and obtain a uniform and transparent chitosan solution. Adjust the pH value to 5.8 and monitor and adjust it with a pH meter. If the pH value is low, it can be neutralized by slowly adding an appropriate amount of sodium hydroxide solution (0.1M).
[0025] (2) Preparation of red yeast fermentation broth 1 g of marine red yeast lyophilized powder was added to 9 ml of sterile saline and vortexed in a vortex oscillator at 2800 RPM for 1 min to obtain an inoculum solution; Prepare fermentation medium: 2% glucose, 1% peptone, 2% agar, 0.5% yeast extract, 1% corn starch and 1000 ml seawater; The inoculum was added to the sterilized fermentation medium at an inoculum amount of 3% (v / v), and the culture was carried out at 28°C for 48 hours until the pH value of the fermentation liquid dropped to 7.8; solid impurities were removed by centrifugation to obtain red yeast fermentation liquid.
[0026] (3) Curing 50 ml of chitosan solution and 50 ml of red yeast fermentation liquid were mixed, 2 g of glutaraldehyde was added, and the mixture was allowed to stand and solidify at 4° C. for 3 hours to obtain the chitosan-red yeast composite microparticles.
[0027] Example 2: A chitosan-red yeast composite microparticle The chitosan-red yeast composite microparticles of this embodiment are prepared by the following steps: (1) Preparation of chitosan solution First, weigh 1.2g chitosan and dissolve it in 100ml of 1% (v / v) glacial acetic acid aqueous solution, heat it to 45℃, use a magnetic stirrer until the chitosan is completely dissolved, and obtain a uniform and transparent chitosan solution. Adjust the pH value to 5.8 and monitor and adjust it with a pH meter. If the pH value is low, it can be neutralized by slowly adding an appropriate amount of sodium hydroxide solution (0.1M).
[0028] (2) Preparation of red yeast fermentation broth 1 g of marine red yeast lyophilized powder was added to 9 ml of sterile saline and vortexed in a vortex oscillator at 2800 RPM for 1 min to obtain an inoculum solution; Prepare fermentation medium: 2% glucose, 1% peptone, 2% agar, 0.5% yeast extract, 1% corn starch and 1000 ml seawater; The inoculum was added to the sterilized fermentation medium at an inoculum amount of 3% (v / v), and the culture was carried out at 28°C for 48 hours until the pH value of the fermentation liquid dropped to between 7.8; solid impurities were removed by centrifugation to obtain red yeast fermentation liquid.
[0029] (3) Curing 50 ml of chitosan solution and 50 ml of red yeast fermentation liquid were mixed, 2 g of glutaraldehyde was added, and the mixture was allowed to stand and solidify at 4° C. for 2 hours to obtain the chitosan-red yeast composite microparticles.
[0030] Example 3: A chitosan-red yeast composite microparticle The chitosan-red yeast composite microparticles of this embodiment are prepared by the following steps: (1) Preparation of chitosan solution First, weigh 0.8g chitosan and dissolve it in 100ml of 1% (v / v) glacial acetic acid aqueous solution, heat it to 45℃, use a magnetic stirrer until the chitosan is completely dissolved, and obtain a uniform and transparent chitosan solution. Adjust the pH value to 5.8 and monitor and adjust it with a pH meter. If the pH value is low, it can be neutralized by slowly adding an appropriate amount of sodium hydroxide solution (0.1M).
[0031] (2) Preparation of red yeast fermentation broth 1 g of marine red yeast lyophilized powder was added to 9 ml of sterile saline and vortexed in a vortex oscillator at 2800 RPM for 1 min to obtain an inoculum solution; Prepare fermentation medium: 2% glucose, 1% peptone, 2% agar, 0.5% yeast extract, 1% corn starch and 1000 ml seawater; The inoculum was added to the sterilized fermentation medium at an inoculum amount of 3% (v / v), and the culture was carried out at 28°C for 48 hours until the pH value of the fermentation liquid dropped to between 7.8; solid impurities were removed by centrifugation to obtain red yeast fermentation liquid.
[0032] (3) Curing 50 ml of chitosan solution and 50 ml of red yeast fermentation liquid were mixed, 2 g of glutaraldehyde was added, and the mixture was allowed to stand and solidify for 4 hours at 4° C. to obtain the chitosan-red yeast composite microparticles.
[0033] Examples 1 to 3 all prepared chitosan-red yeast composite microparticles for extending the life of fresh fish fillets, and the effects were similar. The chitosan-red yeast composite microparticles of the examples are used to verify the effects.
[0034] 1. Experimental methods The experimental groups are: Composite microparticle experimental group: Cut the raw fish into 5 cm×5 cm×1 cm fillets, immerse the raw fish fillets in the suspension containing the composite microparticles of Example 1 for 15 min, and take out and drain.
[0035] Uncured microparticle experimental group: Fresh fish meat was cut into 5 cm×5 cm×1 cm fillets, and the fresh fish fillets were immersed in the microparticle suspension containing no glutaraldehyde added and static curing treatment of Example 1 for 15 minutes, and then taken out and drained.
[0036] Chitosan experimental group: Fresh fish meat was cut into 5 cm×5 cm×1 cm fillets, and the fillets were immersed in the chitosan solution prepared in Example 1 for 15 min, and then taken out and drained.
[0037] Rhodotorula experimental group: the fresh fish meat was cut into 5 cm×5 cm×1 cm fillets, and the fillets were immersed in the red yeast fermentation liquid prepared in Example 1 for 15 min, and then taken out and drained.
[0038] Control group: Cut the raw fish into 5 cm×5 cm×1 cm fillets, immerse the fillets in the prepared sterile enzyme-free distilled water for 15 min, and take out and drain.
[0039] All samples were placed in a 4°C refrigerator for 72 hours, and samples were collected at 24h, 48h, and 72h. The number of colonies on fish samples was determined using standard microbiological methods, including homogenization, dilution, plate spreading, inoculation, 33°C culture for 48 hours, colony counting, and result calculation. The results are shown in Table 1. Figure 1 and Figure 2 shown.
[0040] Table 1 Data results of total colony count (log10CFU / g) of five groups of samples From Table 1, Figure 1 and Figure 2 It can be seen that under short-term refrigeration conditions, the total colony count of the experimental group was lower than that of the control group, and the growth rate was slower, indicating that the experimental groups had antibacterial ability against microorganisms. Among the experimental groups, the total colony count of the composite microparticle experimental group was significantly lower than that of the uncured microparticle experimental group, the chitosan experimental group, and the red yeast experimental group, indicating that the composite microparticles had the best antibacterial effect. The total colony counts of the uncured microparticle experimental group, the chitosan experimental group, and the red yeast experimental group were similar, indicating that the three had little difference in antibacterial effect, but the total colony count of the uncured microparticle experimental group was slightly lower, indicating that the uncured chitosan and red yeast mixed solution may have a better inhibitory effect on certain bacteria.
[0041] In summary, the chitosan-red yeast composite microparticles obtained by the method of the present invention can inhibit the growth of harmful microorganisms and reduce oxidation reactions, thereby significantly extending the freshness and shelf life of fresh fish fillets, reducing the use of chemical preservatives, and improving food safety, thus proposing a novel and efficient solution to solve the problem of food preservation safety.
[0042] It should be noted that when the claims of the present invention involve numerical ranges, it should be understood that the two endpoints of each numerical range and any numerical value between the two endpoints can be selected. In order to avoid redundancy, the present invention describes a preferred embodiment.
[0043] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.
Claims
1. A chitosan-red yeast composite microparticle for extending the life of fresh fish fillets, characterized in that: The composite microparticles are prepared by mixing chitosan and red yeast and then solidifying them, wherein the red yeast is wrapped in the chitosan, and the diameter of the chitosan-red yeast composite microparticles is distributed between 50 μm and 100 μm.
2. The chitosan-red yeast composite microparticles according to claim 1, characterized in that: The deacetylation degree of the chitosan is not less than 90%.
3. The chitosan-red yeast composite microparticles according to claim 1, characterized in that: The red yeast is marine red yeast.
4. The method for preparing the chitosan-red yeast composite microparticles according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, mixing red yeast fermentation broth and chitosan solution in equal volume ratio to obtain a mixed solution; S2. Adding 1.8% to 2% by volume of glutaraldehyde into the mixed solution for solidification to obtain the chitosan-red yeast composite microparticles.
5. The method for preparing chitosan-red yeast composite microparticles according to claim 4, characterized in that: The concentration of the red yeast fermentation broth is 1.5×10 10 ~1.8×10 10 cfu / mL.
6. The method for preparing chitosan-red yeast composite microparticles according to claim 4, characterized in that: The chitosan solution has a concentration of 8-12 g / L, and the chitosan solution uses glacial acetic acid with a volume concentration of 0.9%-1.1% as solvent.
7. The method for preparing chitosan-red yeast composite microparticles according to claim 4, characterized in that: The curing condition is to stand at 4-5°C for 3-4 hours.
8. Use of the chitosan-red yeast composite microparticles according to any one of claims 1 to 3 in extending the life of fresh fish fillets.
9. A method for extending the life of fresh fish fillets, characterized in that: The fresh fish fillet is immersed in the suspension of the chitosan-red yeast composite microparticles according to any one of claims 1 to 3 for 10 to 20 minutes, the fresh fish fillet is taken out to remove excess water, a stable film layer is formed on the surface of the fresh fish fillet, and then stored at 4 to 8°C.