Quality control method of dried cordyceps sinensis

Abstract

The invention provides a quality control method of dried cordyceps sinensis, which comprises the following steps: (1) carrying out ultraviolet light catalytic treatment on the dried cordyceps sinensis: irradiating a photocatalytic material and the dried cordyceps sinensis by using an ultraviolet light source with the wavelength of 240-260nm, the dried cordyceps sinensis is arranged above the photocatalytic material in parallel, and the distance between the ultraviolet light source and the dried cordyceps sinensis is 20-30 cm; the irradiation time of the ultraviolet light source is 20-40 minutes; and (2) packaging the dried cordyceps sinensis subjected to ultraviolet light catalysis treatment in a packaging bottle filled with nitrogen. According to the quality control method provided by the invention, ultraviolet light catalytic treatment is combined with nitrogen controlled atmosphere treatment, so that the oxidation reaction and the growth of microorganisms can be effectively inhibited, the shelf life of the product is greatly prolonged, the fresh-keeping effect is remarkably improved, the fresh-keeping purpose is achieved, and the quality control of the dried cordyceps sinensis is realized.

Description

Technical Field

[0001] The invention relates to the technical field of Chinese medicinal material preservation, and in particular to a quality control method for dried cordyceps sinensis. Background Art

[0002] As a precious traditional Chinese medicine, dried Cordyceps sinensis has attracted much attention from consumers for its medicinal value and nutritional content. However, due to its high protein content and high active substance content, dried Cordyceps sinensis is susceptible to microbial contamination and degradation of physical and chemical components during storage, resulting in quality degradation and loss of nutrients, which seriously affects its medicinal effects and market value.

[0003] Existing preservation technologies include nitrogen packaging, vacuum packaging, dehydration, antioxidant treatment, and low-temperature drying and storage. These preservation technologies can extend the storage period of dried Cordyceps sinensis to a certain extent, but these methods still have limitations. For example, nitrogen packaging and vacuum packaging slow down oxidation by reducing oxygen concentration, but have limited effects on microbial control. Although dehydration and antioxidant treatment can inhibit microbial growth and delay oxidation, they may affect the taste and stability of nutrients. Low-temperature drying and storage can effectively slow down oxidation and microbial growth, but the corresponding storage cost is relatively high.

[0004] In recent years, the application of ultraviolet photocatalytic technology in food preservation has gradually attracted widespread attention. Using ultraviolet light to irradiate photocatalysts (such as titanium dioxide (TiO2), vanadium dioxide (V2O5), zinc oxide (ZnO), etc.) can generate ROS with strong oxidizing ability, which can destroy the cell membrane and cell wall of microorganisms, inhibit the reproduction of microorganisms, and effectively reduce the activity of enzymes, thereby reducing the degradation of nutrients, achieving the purpose of food and drug preservation. However, single-step photocatalytic treatment may have problems such as uneven treatment during the preservation of dried Cordyceps sinensis, and the stability and duration of ROS are relatively short.

[0005] Based on this, the present invention is proposed. Summary of the invention

[0006] In order to break through the limitations of the preservation technology in the prior art, the present invention provides a quality control method for dried Cordyceps sinensis, which combines ultraviolet light catalytic treatment with nitrogen gas conditioning, improves the control effect of microorganisms, further reduces the rate of quality deterioration, effectively improves the preservation effect of Cordyceps sinensis, extends its storage period and shelf life, and maintains the stability of its medicinal and nutritional components, showing good practical application potential.

[0007] In one aspect of the present invention, a method for controlling the quality of dried Cordyceps sinensis is provided, comprising: (1) treating the dried Cordyceps sinensis with ultraviolet light: using an ultraviolet light source with a wavelength of 240-260 nm to irradiate a photocatalytic material and the dried Cordyceps sinensis, wherein the photocatalytic material and the ultraviolet light source are arranged in parallel, the dried Cordyceps sinensis is placed above the photocatalytic material in parallel, and the distance between the ultraviolet light source and the dried Cordyceps sinensis is 20-30 cm; the irradiation time of the ultraviolet light source is 20-40 min; (2) Packaging the dried Cordyceps sinensis that has undergone the ultraviolet light catalytic treatment in a packaging bottle filled with nitrogen.

[0008] Dried Cordyceps sinensis contains rich proteins and active substances, which are prone to deterioration in the presence of microorganisms, resulting in quality damage. The quality control method provided by the present invention utilizes ultraviolet light to irradiate photocatalytic materials, which can generate reactive oxygen species (ROS) with strong oxidizing ability, which can destroy the cell membrane and cell wall of microorganisms, inhibit the reproduction of microorganisms, and effectively inhibit enzymatic browning, thereby maintaining the apparent quality of Cordyceps sinensis and reducing the degradation of nutrients; combined with nitrogen gas conditioning treatment, it can further eliminate the unevenness of photocatalytic treatment and the adverse effects of the stability and relatively short duration of ROS, so as to achieve the purpose of preservation and realize the quality control of dried Cordyceps sinensis.

[0009] In some embodiments, the photocatalytic material is selected from at least one of TiO2, V2O5, and ZnO.

[0010] In some embodiments, the particle size of the TiO2 is 0.3-1.2 μm, preferably 0.4-1 μm.

[0011] In some embodiments, in step (1), the ultraviolet photocatalytic treatment is carried out in a photocatalytic treatment device.

[0012] In some embodiments, during the ultraviolet photocatalytic treatment, air is introduced at a wind speed of 1-2 m / s.

[0013] In some embodiments, in step (1), the dried Cordyceps sinensis is placed on the photocatalytic material in a uniform and non-overlapping manner.

[0014] In some embodiments, in step (2), the concentration of oxygen in the packaging bottle is less than 1%; and / or the purity of the nitrogen is greater than 99.9%.

[0015] In some embodiments, in step (2), the volume of the packaging bottle is 50-200cm 3 .

[0016] In some embodiments, the material of the packaging bottle is selected from at least one of PBS, PP, PET, and PVC.

[0017] In some embodiments, the dried Cordyceps sinensis is cleaned to remove surface concrete and / or impurities before the ultraviolet photocatalytic treatment.

[0018] The present invention has at least the following technical effects: (1) The present invention provides for the first time a method for preserving dried Cordyceps sinensis by combining photocatalysis with nitrogen atmosphere treatment. The reactive oxygen species (ROS) generated by ultraviolet light catalysis can rapidly reduce the microbial load on the surface of Cordyceps sinensis, effectively inhibit the activity of enzymes, and thus reduce the incidence of oxidation reactions.

[0019] (2) The present invention provides an innovative technology for extending the shelf life of Cordyceps sinensis by combining photocatalysis with nitrogen atmosphere control. Through nitrogen atmosphere control in small-sized packaging, the oxygen concentration in the packaging bag is ensured to be less than 1%, which effectively inhibits oxidation reactions and microbial growth during storage, greatly extending the shelf life of the product and significantly improving the preservation effect.

[0020] (3) The photocatalytic treatment of the present invention is combined with the nitrogen gas conditioning technology, which can reduce oxidation and enzymatic reactions while maintaining the stability of the nutritional components and medicinal active ingredients of Cordyceps sinensis, reducing the loss of components and ensuring its high quality during long-term storage.

[0021] (4) Photocatalysis and nitrogen gas conditioning treatment technology is environmentally friendly and highly efficient. Compared with traditional chemical preservation methods, the present invention does not require the addition of chemical preservatives. The entire process is green and environmentally friendly, more friendly to the environment and consumers, and further ensures the safety and product quality of Cordyceps sinensis.

[0022] (5) The method of the present invention is suitable for large-scale production and long-distance transportation. The photocatalytic and nitrogen gas conditioning treatment processes are simple, the required equipment is easy to obtain, economical and practical, and can be widely used in industrial production to improve the commercial value and market competitiveness of Cordyceps sinensis.

[0023] In summary, the present invention has developed a method for preserving dried Cordyceps sinensis that combines photocatalytic generation of active oxygen and nitrogen gas conditioning technology, which significantly improves its preservation effect and storage period and ensures the integrity of nutrients and active ingredients. It is an efficient, reliable and environmentally friendly preservation technology that is suitable for large-scale production and long-distance transportation of Cordyceps sinensis. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 This is one of the flow charts of the quality control method for dried Cordyceps sinensis provided by the present invention.

[0026] Figure 2 This is one of the structural schematic diagrams of a photocatalytic treatment device involved in the quality control method for dried Cordyceps sinensis provided by the present invention.

[0027] Reference numerals: 1: Photocatalytic treatment box; 2: Photocatalytic plate; 3: Ultraviolet light source; 4: Sample rack; 5: Blowing equipment. DETAILED DESCRIPTION

[0028] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0029] Generally, the key to the preservation of Cordyceps sinensis is to avoid light, moisture and classification; first, it is believed that ultraviolet rays will destroy its active ingredients, so it should be stored in a cool, dry and ventilated place to avoid direct sunlight; second, it is necessary to ensure that the storage environment is dry, and sealed plastic bags or glass bottles can be used, and hygroscopic agents such as lime bags are placed to keep the interior dry and moisture-proof; third, Cordyceps sinensis of different origins and qualities should be stored separately to avoid mutual influence; fourth, if it is stored for a long time, it can be considered to be refrigerated in the refrigerator to extend its shelf life. For example, Chinese invention patent application CN115367257A specifically discloses a packaging box for storing Cordyceps sinensis, which changes the packaging state in the traditional Cordyceps exhibition and sales process, and can be refrigerated, dried and light-proof for Cordyceps of various qualities, and can effectively meet the moisture-proof, mildew-proof, moth-proof and light-proof storage requirements for Cordyceps preservation, and can maintain the quality of Cordyceps for a long time, which is suitable for long-term exhibition and storage.

[0030] Therefore, the current sterilization methods for Cordyceps sinensis include: saline ultrasonic cold immersion sterilization, ethanol freezing sterilization and vacuum freeze drying sterilization. These methods can effectively kill the microorganisms in Cordyceps sinensis, while maintaining the SOD activity and protein content in Cordyceps sinensis, ensuring the quality and safety of Cordyceps sinensis. Through these sterilization methods, the storage period of Cordyceps sinensis can be extended while maintaining its efficacy.

[0031] Saline ultrasonic cold soak sterilization method: soak fresh Cordyceps sinensis in saline ultrasonic cold soak, filter and collect the soaking liquid; after desalting and concentrating the soaking liquid, spray it evenly on the Cordyceps sinensis; finally, freeze-dry the Cordyceps sinensis;.

[0032] Ethanol freezing sterilization method: crush the Cordyceps sinensis into 60-1000 mesh, add 70-85% ethanol to soak for 0.5-5 hours, the volume of the ethanol solution is 1-5 times the weight of the Cordyceps sinensis, then add 1-5 times the weight of the Cordyceps sinensis pure water, mix and then freeze-dry;.

[0033] Vacuum freeze-drying sterilization method: The pre-frozen Cordyceps sinensis is sublimated and dried at -30°C, with a vacuum degree of 30 bar and a drying time of 30 hours; then it is decomposed and dried at 30°C, with a vacuum degree of 10 bar and a drying time of 3 hours to obtain the sterilized Cordyceps sinensis.

[0034] The preservation technologies for dried Cordyceps sinensis include nitrogen packaging, vacuum packaging, dehydration, antioxidant treatment, and low-temperature drying and storage, but these methods still have limitations. For example, nitrogen packaging and vacuum packaging slow down oxidation by reducing oxygen concentration, but have limited effects on microbial control. Although dehydration and antioxidant treatment can inhibit microbial growth and delay oxidation, they may affect the taste and stability of nutrients. Low-temperature drying and storage can effectively slow down oxidation and microbial growth, but the corresponding storage cost is relatively high.

[0035] On this basis, the present invention provides a quality control method for dried Cordyceps sinensis, comprising: (1) treating the dried Cordyceps sinensis with ultraviolet light: using an ultraviolet light source with a wavelength of 240-260 nm to irradiate a photocatalytic material and the dried Cordyceps sinensis, wherein the photocatalytic material and the ultraviolet light source are arranged in parallel, the dried Cordyceps sinensis is placed above the photocatalytic material in parallel, and the distance between the ultraviolet light source and the dried Cordyceps sinensis is 20-30 cm; the irradiation time of the ultraviolet light source is 20-40 min; (2) Packaging the dried Cordyceps sinensis that has undergone the ultraviolet light catalytic treatment in a packaging bottle filled with nitrogen.

[0036] Among them, the wavelength of the ultraviolet light source can be 240nm, 245nm, 247nm, 250nm, 254nm, 260nm, etc., or it can be a range consisting of these specific wavelengths, such as 245-254nm, 247-254nm, 250-260nm, etc.; the distance between the ultraviolet light source and the dried Cordyceps sinensis is 20cm, 22cm, 24cm, 25cm, 28cm, 30cm, etc., or it can be a range consisting of these specific distances, such as 25-30cm, 20-25cm, 22-28cm, 20-26cm, etc.; the irradiation time of the ultraviolet light source can be 20min, 25min, 30min, 35min, 40min, etc., or it can be a range consisting of these specific time values, such as 25-35min, 20-35min, 25-40min, etc.; the specific values ​​and the ranges they constitute are not listed one by one here.

[0037] It has been verified that the quality control method provided in this application, which utilizes ultraviolet light to irradiate titanium dioxide photocatalytic materials to generate reactive oxygen species (ROS), can effectively inhibit microorganisms. Combined with nitrogen atmosphere storage, it can effectively extend the shelf life of Cordyceps sinensis and maintain its quality and nutritional content.

[0038] In some embodiments, the photocatalytic material is selected from at least one of TiO2, V2O5, and ZnO. TiO2 has good photocatalytic activity, catalytic performance in a wide wavelength band, and relatively low cost. The photocatalytic material can be loaded on a photocatalytic plate as a coating, or fixed on a porous matrix to achieve a more efficient photocatalytic effect.

[0039] In some embodiments, the particle size of the TiO2 is 0.3-1.2 μm. The use of TiO2 with the above particle size has the effects of high active oxygen generation efficiency, stable catalytic performance, and balanced economy and practicality, such as 0.3 μm, 0.4 μm, 0.5 μm, 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1.0 μm, 1.1 μm, 1.2 μm, or other particle sizes within the above range, or a range consisting of these specific particle sizes, such as 0.4-1 μm, 0.4-0.6 μm, 0.6-0.8 μm, 0.6-1.0 μm, 0.8-1.2 μm, 0.6-1.2 μm, etc. Preferably, the particle size of the TiO2 is 0.4-1 μm.

[0040] In some embodiments, in step (1), the ultraviolet light catalytic treatment is performed in a photocatalytic treatment device. Performing the photocatalytic treatment in a relatively closed space can achieve better results.

[0041] In some embodiments, during the ultraviolet light catalytic treatment, air is introduced at a wind speed of 1-2 m / s, and the wind speed may be 1 m / s, 1.2 m / s, 1.5 m / s, 1.8 m / s, 2 m / s, etc., or may be a range of these specific wind speeds, such as 1-1.8 m / s, 1.5-2 m / s, 1.2-1.8 m / s, etc. It has been verified that during the ultraviolet light catalytic treatment, introducing air at the above wind speed can improve the uniformity of the photocatalytic treatment and enhance the spatial distribution efficiency of the photocatalytic treatment.

[0042] In some embodiments, the dried Cordyceps sinensis is placed on the photocatalytic material in a uniform and non-overlapping manner, with a placement density of ≤25 cordyceps / 100 cm 2 .

[0043] In some embodiments, in step (2), the concentration of oxygen in the packaging bottle is less than 1%; and / or the purity of the nitrogen is greater than 99.9%; thereby ensuring a low oxygen environment inside the packaging bottle, effectively inhibiting the oxidation reaction and microbial reproduction of Cordyceps sinensis during storage.

[0044] In some embodiments, in step (2), the volume of the packaging bottle is 50-200 cm 3 , such as 50cm 3 , 60cm 3 , 70cm 3 , 80cm 3 , 90cm 3 , 100cm 3 , 120cm 3 , 150cm 3 , 160cm 3 , 180cm 3 , 200cm 3 , or it can be a range of these specific volumes, such as 50-100cm 3 , 60-80cm 3 , 70-120cm 3 , 100-200cm 3 , 100-180cm 3 It has been verified that these small-sized packaging bottles have good sealing performance, high gas replacement efficiency, and are easy to store and transport.

[0045] In some embodiments, the material of the packaging bottle is selected from at least one of PBS, PP, PET, and PVC. The packaging bottle is made of composite materials such as PBS and PP with good barrier properties, which can effectively prevent oxygen penetration and inflation (nitrogen) leakage, ensuring a good preservation effect.

[0046] In some embodiments, the quality control method further includes cleaning the dried Cordyceps sinensis before the ultraviolet photocatalytic treatment to remove surface concrete and / or impurities, thereby providing good baseline conditions for the subsequent photocatalytic process and optimizing the catalytic reaction efficiency.

[0047] In some specific embodiments, the quality control method is as follows: Figure 1 As shown, the following steps are included: (I) Preliminary cleaning: Collect dried Cordyceps sinensis samples and perform preliminary cleaning to ensure that there is no obvious dirt or impurities on the sample surface, thereby providing good baseline conditions for the subsequent photocatalytic process and optimizing the catalytic reaction efficiency.

[0048] (ii) Ultraviolet photocatalytic treatment, using Figure 1 Photocatalytic treatment device shown (1) Photocatalytic material and sample arrangement: The photocatalytic material TiO2 is evenly embedded in the photocatalytic plate 2 of the photocatalytic device (the particle size is 0.3-1.2 μm, preferably 0.4-1 μm TiO2 is loaded on the surface of the catalyst plate as a coating), and is placed parallel to the ultraviolet light source 3 to ensure that the photocatalytic material is fully in contact with the ultraviolet light. The cleaned dried Cordyceps sinensis samples are evenly placed on the food-grade sample rack 4 (the sample rack 4 is placed on the photocatalytic plate 2 loaded with the TiO2 coating, and the sample rack 4 is kept parallel to the ultraviolet light source 3) to maximize the exposure of the dried Cordyceps sinensis to the ultraviolet light and active oxygen environment, thereby improving the uniformity and efficiency of photocatalysis.

[0049] (2) Ultraviolet photocatalytic treatment: The arranged Cordyceps sinensis samples are placed in a photocatalytic box 1 and irradiated with an ultraviolet lamp with a wavelength of 254 nm as an ultraviolet light source 3. The distance between the ultraviolet lamp and the sample is 20-30 cm, and the irradiation time is 20-40 minutes. In this process, ultraviolet irradiation of the TiO2 photocatalytic material generates ROS, thereby effectively inhibiting the growth of microorganisms on the sample surface, and reducing the activity of enzymes to a certain extent, reducing the oxidative degradation of nutrients.

[0050] During the ultraviolet photocatalytic treatment process, the air blowing device 5 is used to introduce air into the photocatalytic treatment box 1 to ensure that the active oxygen is evenly distributed to every part of the dried Cordyceps sinensis sample. The wind speed is maintained at 1-2 m / s to ensure uniform photocatalytic treatment and improve the spatial distribution efficiency of photocatalysis.

[0051] (III) Nitrogen atmosphere treatment for small-sized packaging of dried Cordyceps sinensis (1) Small-sized packaging: After the UV-photocatalytic treatment, the dried Cordyceps sinensis is packed into specially made small-sized packaging bottles (volume is about 50-200 cm 3), these packaging bottles should be made of composite materials with good barrier properties such as PBS and PP to prevent oxygen penetration and inflation leakage, ensuring good preservation effect.

[0052] (2) Nitrogen filling and sealing: The packaging bag is sealed in a nitrogen filling environment. The nitrogen purity requirement is not less than 99.9%. During the filling process, the oxygen concentration in the packaging bag is kept below 1%. This process ensures a low-oxygen environment inside the package, effectively inhibiting the oxidation reaction and microbial reproduction of Cordyceps sinensis during storage.

[0053] The above method, through the combined application of photocatalysis and nitrogen gas conditioning treatment, has demonstrated significant advantages in microbial control, nutrient retention and oxidation inhibition, thereby effectively improving the preservation effect and quality of dried Cordyceps sinensis, thereby increasing its market value.

[0054] In the examples, information of each raw material is shown in Table 1 below.

[0055] Table 1 Raw material information

[0056] If no specific techniques or conditions are specified in the examples, the techniques or conditions described in the literature in the field or the product instructions are used. If no manufacturer is specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0057] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0058] Example 1 This embodiment provides a method for quality control of dried Cordyceps sinensis: quality control of 20 dried Cordyceps sinensis by photocatalysis for 20 minutes combined with nitrogen atmosphere packaging, and the specific steps are as follows: (1) Take 20 dried Cordyceps sinensis and perform preliminary cleaning to ensure that there is no obvious dirt or impurities on the surface of the sample; (2) Place the sample on the photocatalytic device shelf, with the distance between the UV light source and the sample shelf being 20 cm; (3) Irradiate the sample with ultraviolet light at a wavelength of 254 nm for 20 minutes; (4) The TiO2 coating structure is evenly distributed on the photocatalytic plate in the device. The air blowing device is started and the wind speed is set to 1 m / s to ensure that the active oxygen is evenly distributed on the sample surface and improve the photocatalytic efficiency. (5) After the treatment, the samples were packaged in small-sized bottles (cylindrical, diameter*height=4cm*8cm) and sealed in a nitrogen atmosphere with the oxygen concentration kept below 1%. They were stored at high temperature and high humidity (30°C, 80% humidity).

[0059] Example 2 This embodiment provides a method for quality control of dried Cordyceps sinensis: quality control of 40 dried Cordyceps sinensis by photocatalysis for 25 minutes combined with nitrogen atmosphere packaging, the specific steps are as follows: (1) Take 40 dried Cordyceps sinensis and perform preliminary cleaning to ensure that there is no obvious dirt or impurities on the surface of the sample; (2) Place the sample on the photocatalytic device rack, with the distance between the light source and the sample rack being 25 cm; (3) Irradiate the sample with ultraviolet light at a wavelength of 254 nm for 25 minutes; (4) The TiO2 coating structure is evenly distributed on the photocatalytic plate in the device. The air blowing device is started and the wind speed is set to 1.5m / s to ensure that the active oxygen is evenly distributed on the sample surface and improve the photocatalytic efficiency; (5) After the treatment, the sample is packaged in a small-sized bottle (cylindrical, diameter*height=6cm*8cm) and sealed in a nitrogen atmosphere. The oxygen concentration is kept below 1%. Store at high temperature and high humidity (30℃, 80% humidity).

[0060] Example 3 This embodiment provides a method for quality control of dried Cordyceps sinensis: quality control of 60 dried Cordyceps sinensis by photocatalysis for 30 minutes combined with nitrogen atmosphere packaging, the specific steps are as follows: (1) Take 60 dried Cordyceps sinensis and perform preliminary cleaning to ensure that there is no obvious dirt or impurities on the surface of the sample; (2) Place the sample on the photocatalytic device rack, with the distance between the light source and the sample rack being 30 cm; (3) Irradiate the sample with ultraviolet light at a wavelength of 254 nm for 30 minutes; (4) The TiO2 coating structure is evenly distributed on the photocatalytic plate in the device. The air blowing device is started and the wind speed is set to 2 m / s to ensure that the active oxygen is evenly distributed on the sample surface and improve the photocatalytic efficiency. (5) After treatment, the samples were packaged in small-sized bottles (cylindrical, diameter*height=8cm*8cm) and sealed in a nitrogen atmosphere with the oxygen concentration kept below 1%. They were stored at high temperature and high humidity (30°C, 80% humidity).

[0061] Comparative Example 1 This comparative example provides a method for quality control of dried Cordyceps sinensis: UV irradiation for 25 minutes combined with nitrogen atmosphere packaging to control the quality of 40 dried Cordyceps sinensis, the specific steps are as follows: (1) Take 40 dried Cordyceps sinensis and perform preliminary cleaning to ensure that there is no obvious dirt or impurities on the surface of the sample; (2) Place the sample on the device rack with the distance between the light source and the sample rack being 25 cm.

[0062] (3) Irradiate the sample with ultraviolet light at a wavelength of 254 nm for 25 minutes.

[0063] (4) Only UV irradiation was performed and the wind speed was set to 1.5 m / s.

[0064] (5) After the treatment, the samples were packaged in small-sized bottles (cylindrical, diameter*height=6cm*8cm) and sealed in a nitrogen atmosphere with the oxygen concentration kept below 1%. They were stored at high temperature and high humidity (30°C, 80% humidity).

[0065] Comparative Example 2 This comparative example provides a method for quality control of dried Cordyceps sinensis: quality control of 40 dried Cordyceps sinensis by photocatalysis for 25 minutes, and the specific steps are as follows: (1) Take 40 dried Cordyceps sinensis and perform preliminary cleaning to ensure that there is no obvious dirt or impurities on the surface of the sample; (2) Place the sample on the photocatalytic device rack, with the distance between the light source and the sample rack being 25 cm; (3) Irradiate the sample with ultraviolet light at a wavelength of 254 nm for 25 minutes; (4) The TiO2 coating structure is evenly distributed on the photocatalytic plate in the device, and the wind speed is set to 1.5 m / s; (5) After processing, seal and package directly in air environment and store at high temperature and high humidity (30℃, 80% humidity).

[0066] Comparative Example 3 This comparative example provides a quality control method for dried Cordyceps sinensis, which is basically the same as Example 2, except that the dried Cordyceps sinensis is subjected to a preliminary cleaning treatment to remove obvious dirt or impurities on the surface, and then directly subjected to nitrogen gas conditioning treatment: the dried Cordyceps sinensis is packed into a packaging bottle and sealed in a nitrogen-filled environment, and then stored.

[0067] Comparative Example 4 This comparative example provides a quality control method for dried Cordyceps sinensis, which is basically the same as Example 2, except that the dried Cordyceps sinensis is preliminarily cleaned to remove obvious dirt or impurities on the surface, and then directly packaged in an air environment without photocatalytic treatment and nitrogen gas conditioning: the dried Cordyceps sinensis is put into a packaging bottle, and stored directly after being sealed in an air environment.

[0068] Through the experiments of these embodiments and comparative examples, it can be verified that the present invention has significant advantages in microbial inhibition, nutrient retention and oxidation inhibition.

[0069] Test Example 1 Test object: dried Cordyceps sinensis stored for different periods of time using the quality control methods in the embodiments and comparative examples.

[0070] Test method: Sensory evaluation was conducted and the malondialdehyde content, moisture content, superoxide dismutase (SOD) activity and polyphenol oxidase (PPO) activity were determined.

[0071] (1) Sensory evaluation: A specially trained sensory evaluation team (24 people) gave a comprehensive score to the sensory quality of fresh Cordyceps after thawing according to the evaluation criteria in Table 2, and finally took the average value. The average of the five indicators was taken as the final sensory evaluation result. A score of <6 indicated that a significant quality deterioration had occurred.

[0072] Table 2 Sensory evaluation standards for Cordyceps sinensis

[0073] (2) Determination of MDA Referring to Yan et al. (Variation in cell membrane integrity and enzyme activity of the button mushroom (Agaricus bisporus) during storage and transportation. Journal of Food Science and Technology, 2021, 58:1655-1662), 0.5 g of dried Cordyceps sinensis was immersed in 5 mL of 100 g / L trichloroacetic acid (TCA), centrifuged at 9000×g for 20 min at 4°C, and 0.3 mL of MDA supernatant was mixed with 3 mL of 0.5% thiobarbituric acid solution. Then, the mixture was heated at 100°C for 20 minutes and cooled to room temperature. The absorbance of the mixture was measured at 450 nm, 532 nm, and 600 nm, and the MDA content was calculated using the formula: c (μ / mol) = (OD532-OD600) × 6.45-OD450 × 0.56.

[0074] (3) The determination of moisture content shall refer to the method in GB 5009.3-2016 National Food Safety Standard Determination of Moisture in Food.

[0075] (4) The activity of superoxide dismutase (SOD) can be determined by the xanthine oxidase method. The specific steps are as follows: First, prepare a reaction solution containing 0.05M phosphate buffer (pH 7.8), 0.1mM EDTA, 0.1mM xanthine and 0.025mM nitroblue tetrazolium (NBT). Then, mix the sample with the reaction solution and react at room temperature for 5 minutes. Next, add 0.1U / mL xanthine oxidase to start the reaction, and measure the absorbance change at a wavelength of 560nm. SOD activity is calculated by the ability to inhibit the reduction of NBT to generate a blue product, and the unit is defined as the amount of enzyme required for 50% inhibition.

[0076] (5) The specific steps for determining the activity of polyphenol oxidase (PPO) are as follows: Take 0.5 g of dried Cordyceps sinensis, add an appropriate amount of phosphate buffer and grind into a homogenate, centrifuge at 4°C and 12,000×g for 30 min, and collect the supernatant as the enzyme extract. Add 4.0 mL of 50 mmol / L, pH 5.5 acetate buffer and 1.0 mL of 50 mmol / L catechol solution, and finally add 100 µL of enzyme extract, and start timing immediately. Pour the reaction mixture into a colorimetric cup and place it in the sample chamber of the spectrophotometer. Using distilled water as a reference, record the absorbance of the reaction system at a wavelength of 420 nm after 15 s of reaction. The PPO activity unit (U) is defined as the amount of enzyme required for the absorbance value of 1 g of dried Cordyceps sinensis to change by 0.01 in 1 min.

[0077] Test results: See Table 3 for the results.

[0078] Table 3 Sensory evaluation, malondialdehyde content, water content, and SOD and PPO activity results of dried Cordyceps sinensis As can be seen from Table 3, the sensory evaluation, malondialdehyde (MDA) content, moisture content, PPO and SOD enzyme activity of Example 1, Example 2 and Example 3 during storage at high temperature and high humidity (30°C, 80% humidity) are better than those of Comparative Example 1, Comparative Example 2 and Comparative Example 3. The sensory scores of the Example group at each time point were significantly higher than those of the Comparative Example group, showing better appearance and quality retention effects. In terms of malondialdehyde content, the Example group showed lower values, indicating that the treatment method of the present invention has significant advantages in inhibiting lipid oxidation. In addition, the SOD enzyme activity of the Example group was significantly higher than that of the Comparative Example group, further demonstrating the effectiveness of photocatalysis combined with nitrogen gas conditioning technology in maintaining antioxidant activity.

[0079] By comparing Example 2 with Comparative Example 1, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen generated is sterilized, which can achieve a better sterilization effect, so that it is not easy to deteriorate during the subsequent storage process, which is more conducive to the sensory preservation of dried Cordyceps sinensis; the malondialdehyde content is lower, which is more conducive to reducing the quality deterioration caused by lipid oxidation, and the PPO activity is lower, which further reduces the risk of enzymatic browning; SOD activity is higher, proving that photocatalysis enables product quality and antioxidant capacity to be better maintained during storage.

[0080] By comparing Example 2 and Comparative Example 2, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning treatment, the photocatalytic material is sterilized by ultraviolet light irradiation. Compared with direct packaging in the air, nitrogen gas conditioning treatment is used, so that it is not easy to deteriorate during subsequent storage, which is more conducive to the sensory preservation of dried Cordyceps sinensis; the malondialdehyde content is lower, which is more conducive to reducing the accumulation of oxidation products, and the PPO activity is lower, which reduces the quality degradation caused by enzymatic oxidation; SOD activity is higher, indicating the significant advantage of nitrogen gas conditioning technology in maintaining the activity of antioxidant enzymes.

[0081] By comparing Example 2 and Comparative Example 3, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, ultraviolet light irradiation and active oxygen sterilization produced by photocatalytic materials can achieve a better sterilization effect. Compared with the treatment with nitrogen gas conditioning only, the subsequent storage process is less likely to deteriorate in quality, which is beneficial to the sensory preservation of dried Cordyceps sinensis; the malondialdehyde content is lower, which is more conducive to inhibiting oxidation reactions, and the PPO activity is lower, which helps to delay quality degradation. This further reflects the superiority of the present invention in quality maintenance.

[0082] By comparing Example 2 and Comparative Example 4, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the active oxygen sterilization produced by ultraviolet light irradiation and photocatalytic materials, combined with nitrogen gas conditioning treatment, can significantly reduce the microbial load and oxidation reaction. Compared with direct encapsulation in an air environment, microbial corruption and quality deterioration are less likely to occur during subsequent storage, which is beneficial to the sensory preservation of dried Cordyceps sinensis; the malondialdehyde content is significantly reduced, effectively inhibiting lipid oxidation reactions; PPO activity is lower, which helps to delay enzymatic browning and quality deterioration. At the same time, SOD activity is maintained at a high level, further proving the significant advantages of the method of the present invention in inhibiting oxidative stress and prolonging the storage quality of Cordyceps sinensis.

[0083] Test Example 2 Test object: dried Cordyceps sinensis stored for different periods of time using the quality control methods in the embodiments and comparative examples.

[0084] Test method: Determine the contents of total sugar (i.e. Cordyceps polysaccharides), cordycepin and adenosine.

[0085] (1) The determination of total sugar content refers to the method in GB / T 15672-2009 “Determination of total sugar content in edible fungi”.

[0086] (2) The method for determining cordycepin and adenosine is as follows: 0.2 g of Cordyceps sinensis sample was weighed into an EP tube, 8 mL of water was added, and ultrasonic extraction was performed for 60 min, during which the sample was shaken several times, and centrifuged at 8000 r / min for 8 min. The supernatant was taken and fixed to 10 mL. After taking an appropriate amount of supernatant, it was filtered through a 0.22 μm syringe filter and then tested on the machine. The detection wavelength was 260 nm, C18 reverse phase chromatographic column (250 mm x4.6 mm, 5 μm), column temperature was 30 °C; mobile phase A was water, and mobile phase B was methanol solution. Gradient elution: 0~5 min, 95%→85%A; 5~10 min, 85%→80%A; 10~20 min, 80%→60%A; 21~28 min, 5%A; 29~40 min, 95%A; flow rate was 0.5 mL / min, and injection volume was 10 μL. At the same time, weigh adenosine and cordycepin standards, dissolve them in water to prepare standard solutions of different mass concentrations. According to the above conditions, the peak area of ​​the standard solution is detected in turn, and the standard curve is calculated with the peak area as the ordinate and the concentration as the abscissa. Substitute the peak area measured by the sample into the standard curve and calculate the corresponding content.

[0087] Test results: See Table 4 for the results.

[0088] Table 4 Determination results of cordyceps polysaccharide, cordycepin and adenosine content in dried Cordyceps sinensis

[0089] As can be seen from Table 4, the cordyceps polysaccharide, adenosine and cordycepin contents of Examples 1, 2 and 3 during storage at high temperature and high humidity (30°C, 80% humidity) were significantly higher than those of Comparative Examples 1, 2, 3 and 4. The cordyceps polysaccharide content of the Example group at 90 days was significantly higher than that of the Comparative Example group, showing a better nutrient retention effect. In terms of adenosine and cordycepin contents, the Example group maintained a high level throughout the storage period, indicating that the method of the present invention has significant advantages in maintaining the nutritional components of Cordyceps sinensis.

[0090] By comparing Example 2 with Comparative Example 1, it can be seen that in the quality control of dried Cordyceps sinensis, after the preliminary cleaning treatment, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen generated is sterilized, which can achieve a better sterilization effect, making it less likely for quality deterioration to occur during the subsequent storage process, and is more conducive to the preservation of the active ingredients and nutrients therein.

[0091] By comparing Example 2 and Comparative Example 2, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen generated is sterilized. Compared with direct packaging in an air environment, the nitrogen atmosphere treatment makes it less likely to deteriorate in quality during subsequent storage, which is more conducive to the preservation of active ingredients and nutrients therein.

[0092] By comparing Example 2 and Comparative Example 3, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen produced is sterilized, which can have a better sterilization effect. Combined with nitrogen gas conditioning treatment, it is not easy to deteriorate during the subsequent storage process, which is more conducive to the maintenance of active ingredients and nutrients. In Comparative Example 3, although preliminary cleaning treatment is performed, the sterilization effect of active oxygen produced by photocatalysis is not performed, and quality control is only performed by nitrogen gas conditioning environment. Therefore, the microbial load on the surface of the sample is high, and it is easy to reproduce in a high temperature and high humidity environment, and there is a lack of effective means to inhibit enzymatic reactions, resulting in the cordycepin, cordyceps polysaccharide and adenosine content being lower than that in Examples 1-3 after storage.

[0093] By comparing Example 2 and Comparative Example 4, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the active oxygen generated by ultraviolet light irradiation photocatalytic materials is sterilized, and combined with nitrogen gas conditioning treatment, microbial growth and enzymatic reactions can be more effectively inhibited, making it less likely to deteriorate in quality during subsequent storage, which is significantly beneficial to the maintenance of active ingredients and nutrients. Comparative Example 4 is directly packaged in an air environment. Due to the high microbial load on the surface of the sample, the high oxygen concentration, and the more active microbial and enzymatic reactions in a high temperature and high humidity environment, cordyceps polysaccharides, adenosine and cordycepin are degraded, further verifying the significant advantages of the method of the present invention in inhibiting the loss of nutrients and maintaining the quality of Cordyceps sinensis.

[0094] Test Example 3 Test object: dried Cordyceps sinensis stored for different periods of time using the quality control methods in the embodiments and comparative examples.

[0095] Test method: The free radical scavenging ability of ABTS (2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid) and DPPH (1,1-diphenyl-2-trinitrophenylhydrazine) was determined.

[0096] (1) The free radical scavenging ability of ABTS (2,2'-azobis-3-ethylbenzothiazoline-6-sulfonic acid) was determined by referring to Hanani et al. (Effect of pomegranate (Punica granatum L.) peel powder on theantioxidant and antimicrobial properties of fish gelatin films as activepackaging. Food Hydrocolloids, 2019, 89:253-259.). 7 mM ABTS solution and 2.45 mM potassium persulfate solution were prepared respectively and mixed in equal amounts (1:1, v / v). The mixture was placed at room temperature in the dark for 12-16 h to obtain the ABTS stock solution. The ABTS stock solution was diluted with distilled water until its absorbance at 734 nm was 0.70±0.02. The diluted solution was used for subsequent experiments. Take 80 μL of Cordyceps sinensis water extract and 8 mL of ABTS diluent, mix them evenly, and react in the dark for 10 minutes. Then measure the absorbance at 734 nm. The blank control is an equal amount of distilled water.

[0097] (2) The determination of DPPH (1,1-diphenyl-2-trinitrophenylhydrazine) free radical scavenging ability was carried out according to Henriques et al. (Characterization of protein hydrolysates from fish discards and by-productsfrom the North-West Spain fishing fleet as potential sources of bioactive peptides. Marine Drugs, 2021, 19(6), 338.). 0.5 mL of sample solution of different concentrations and 5 mL of DPPH solution were mixed evenly and reacted at room temperature in the dark for 30 min. The absorbance was then measured at 517 nm. The blank control was replaced with an equal amount of distilled water, and vitamin C solution was used as a positive control.

[0098] Test results: See Table 5.

[0099] Table 5 Results of free radical scavenging ability test of dried Cordyceps sinensis

[0100] As can be seen from Table 5, the free radical scavenging abilities (ABTS, DPPH) of Examples 1, 2, and 3 during storage at high temperature and high humidity (30°C, 80% humidity) are better than those of Comparative Examples 1, 2, and 3. The antioxidant activities of ABTS and DPPH in the Example group at each time point were significantly higher than those in the Comparative Example group, showing stronger antioxidant ability. This further proves the effectiveness of photocatalysis combined with nitrogen gas conditioning treatment in maintaining the antioxidant ability of Cordyceps sinensis.

[0101] By comparing Example 2 with Comparative Example 1, it can be seen that in the quality control of dried Cordyceps sinensis, after the preliminary cleaning treatment, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen generated kills bacteria, effectively inhibits the growth of microorganisms and the activity of enzymatic reactions, and reduces lipid oxidation reactions. In particular, when the oxidation-related PPO activity is significantly inhibited, the antioxidant components in Cordyceps (such as Cordyceps polysaccharides and adenosine) are better retained. These antioxidant components make it more capable of scavenging oxygen free radicals.

[0102] By comparing Example 2 and Comparative Example 2, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen generated is sterilized. Compared with direct packaging in an air environment, the nitrogen atmosphere treatment makes it less likely for quality deterioration to occur during subsequent storage, further reduces the occurrence of oxidation reactions, and effectively protects key antioxidant components such as cordycepin, cordyceps polysaccharides and adenosine, which are directly involved in the reaction of scavenging ABTS and DPPH free radicals, thereby improving the oxygen free radical scavenging ability of the sample.

[0103] By comparing Example 2 and Comparative Example 3, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the photocatalytic material is irradiated with ultraviolet light, and the active oxygen generated is sterilized, which can have a better sterilization effect. Combined with nitrogen gas conditioning treatment, it is not easy to deteriorate the quality during the subsequent storage process, and the oxidation reaction caused by microorganisms and the degradation of nutrients such as cordycepin, cordyceps polysaccharides and adenosine are effectively delayed, thereby making its oxygen free radical scavenging ability stronger.

[0104] By comparing Example 2 and Comparative Example 4, it can be seen that in the quality control of dried Cordyceps sinensis, after preliminary cleaning, the active oxygen generated by the photocatalytic material is sterilized by ultraviolet light irradiation, and combined with nitrogen gas conditioning treatment, compared with packaging in a direct air environment, it can effectively inhibit the growth of microorganisms and delay the quality deterioration during storage, effectively maintain the levels of components such as Cordyceps polysaccharides, adenosine and cordycepin, and inhibit the decline of oxygen free radical scavenging ability.

[0105] The above results show that compared with Comparative Examples 1, 2, 3, and 4, which are not treated with a photocatalytic layer, not treated with nitrogen filling, treated with nitrogen filling only, or directly packaged without treatment, the photocatalytic combined with nitrogen gas conditioning treatment technology of the present invention has obvious advantages in maintaining the quality and nutritional components of Cordyceps sinensis. The present invention provides a scientific and effective solution for the long-term storage of Cordyceps sinensis, and has significant application prospects and innovation.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the quality of dried Cordyceps sinensis, characterized in that: include: (1) treating the dried Cordyceps sinensis with ultraviolet light: using an ultraviolet light source with a wavelength of 240-260 nm to irradiate a photocatalytic material and the dried Cordyceps sinensis, wherein the photocatalytic material and the ultraviolet light source are arranged in parallel, the dried Cordyceps sinensis is placed above the photocatalytic material in parallel, and the distance between the ultraviolet light source and the dried Cordyceps sinensis is 20-30 cm; the irradiation time of the ultraviolet light source is 20-40 min; (2) Packaging the dried Cordyceps sinensis that has undergone the ultraviolet light catalytic treatment in a packaging bottle filled with nitrogen.

2. The quality control method according to claim 1, characterized in that: The photocatalytic material is selected from TiO 2、 At least one of V2O5 and ZnO.

3. The quality control method according to claim 2, characterized in that: The particle size of the TiO2 is 0.3 μm - 1.2 μm, preferably 0.4 μm - 1 μm.

4. The quality control method according to any one of claims 1 to 3, characterized in that: In step (1), the ultraviolet photocatalytic treatment is carried out in a photocatalytic treatment device.

5. The quality control method according to claim 4, characterized in that: During the ultraviolet catalytic treatment, air is introduced at a wind speed of 1-2 m / s.

6. The quality control method according to any one of claims 1 to 5, characterized in that: In step (1), the dried cordyceps is placed on the photocatalytic material in a uniform and non-overlapping manner, with a placement density of ≤25 cordyceps / 100 cm 2 .

7. The quality control method according to any one of claims 1 to 6, characterized in that: In step (2), the concentration of oxygen in the packaging bottle is less than 1%; And / or, the purity of the nitrogen is above 99.9%.

8. The quality control method according to any one of claims 1 to 7, characterized in that: In step (2), the volume of the packaging bottle is 50-200cm 3 .

9. The quality control method according to any one of claims 1 to 8, characterized in that: The material of the packaging bottle is selected from at least one of PBS, PP, PET and PVC.

10. The quality control method according to any one of claims 1 to 9, characterized in that: The method also includes cleaning the dried Cordyceps sinensis to remove surface concrete and / or impurities before the ultraviolet light catalytic treatment.

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