1037 results about "Food preservation" patented technology

The invention relates to a food fresh-keeping method, device and equipment and a storage medium, and the method comprises the steps: collecting respiration intensity data and decay gas concentration of target food in a cold chain carriage, carrying out fresh-keeping threshold matching, and generating food fresh-keeping information; real-time environment parameters of the cold chain compartment are collected, a fresh-keeping instruction is generated according to the food fresh-keeping information and the real-time environment parameters, and an air adjusting valve opening instruction and a compressor frequency instruction are obtained; dynamic regulation and control operation is executed based on the air regulating valve opening instruction and the compressor frequency instruction, and putrefying bacterium comprehensive evaluation indexes and compressor power consumption data are obtained in real time; and according to the putrefying bacterium comprehensive evaluation index and the compressor power consumption data, instruction feedback analysis is carried out, strategy construction is carried out, and a fresh-keeping regulation and control strategy is output. The air conditioning and refrigeration strategy can be dynamically adjusted according to the breathing characteristics of different foods and the growth dynamic state of putrefying bacteria.

The invention belongs to the technical field of high polymer materials, and discloses a modified bamboo fiber full-biodegradable material, with PBAT, PLA, modified bamboo powder, a plasticizer and a composite antibacterial agent as raw materials, the preparation method comprises the following steps: S1, carrying out alkali treatment modification and silane coupling agent modification on bamboo powder; s2, preparing a composite antibacterial agent by adopting a solid-phase reaction method; s3, all the components with the set amount are fully stirred; s4, carrying out high-temperature melt extrusion on the mixed component raw materials, cooling and pelletizing; s5, the particles are subjected to high-temperature tape casting, and sheets are obtained; and S6, the sheet is formed through plastic uptake. According to the modified bamboo fiber full-biodegradable material disclosed by the invention, due to the addition of the modified bamboo powder, not only can the mechanical properties of food packages be effectively improved, but also the production cost of degradable food packages can be reduced, and the degradation rate of the food packages can be increased; the compound antibacterial agent is added, so that the food package is endowed with excellent antibacterial performance, and the metabolic process of the litchis is delayed, so that the weight loss rate and the rotting rate of the litchis during storage are remarkably reduced, the shelf life of the litchis can be effectively prolonged, and meanwhile, the preservative can be applied to fresh-keeping storage of other fruits and has wide applicability.

The invention belongs to the technical field of functional Pickering emulsion preparation, and particularly discloses a silk fibroin nanoparticle-stabilized biphase drug-loaded Pickering emulsion and an antibacterial application thereof. The curcumin-loaded silk fibroin nanoparticles Cur-SFNPs with uniform form and size are prepared by using an anti-solvent precipitation method. In order to improve the antibacterial effect of the Pickering emulsion, the Cur-SFNPs is utilized to stabilize the soybean oil loaded with resveratrol, and the oil-in-water type Pickering emulsion is prepared. The Pickering emulsion prepared by taking Cur-SFNPs as a stabilizer has the characteristics of small particle size, uniform distribution, storage stability, heating stability, freeze-thaw stability, food safety and environmental friendliness. And as a two-phase drug-loaded emulsion, two natural hydrophobic active drugs are loaded at the same time, so that the solubility and bioavailability of the emulsion can be enhanced, the loaded active substances play a synergistic antibacterial and antioxidant role, and the emulsion can be applied to food preservation.

The invention belongs to the technical field of food preservation, and particularly relates to a field intensity adjusting method based on electrostatic preservation. According to the method, a dynamic field intensity adjusting instruction is generated by obtaining biological impedance data of a to-be-preserved object, the phase difference and the voltage amplitude of the multi-electrode plate array are controlled to form a three-dimensional rotating electric field, and space uniform distribution of field intensity is achieved. The ozone generation module operates independently of an electric field, and the ozone concentration is dynamically adjusted through an ultraviolet light source. A high-frequency short-pulse mode or a low-frequency long-pulse mode is matched according to the type of the object, and the antibacterial and fresh-keeping effects are optimized. Self-adaptive field intensity adjustment is achieved through biological impedance feedback, the three-dimensional rotating electric field and ozone decoupling control are combined, the freshness retaining uniformity and safety are improved, the shelf life is prolonged, and energy consumption is reduced.

The invention relates to the technical field of food preservation, in particular to a vegetable preservation method based on an ultralow-temperature quick-freezing technology. Comprising the following steps: carrying out cleaning and impurity removal treatment on vegetables to be preserved; rapidly cooling the treated vegetables to a temperature ranging from-40 DEG C to-78 DEG C by using an ultra-low temperature technology for not less than 10 minutes; putting the quick-frozen vegetables into a vacuum package, and keeping the freshness of the vegetables in a low-oxygen environment; a natural antioxidant is added in the packaging process, so that the storage life of the vegetables is further prolonged. According to the vegetable fresh-keeping method based on the ultralow-temperature quick-freezing technology, the freezing technology and packaging materials are optimized, so that the storage time of the vegetables is effectively prolonged, and meanwhile, the original color, texture and nutritional ingredients of the vegetables are kept.

The invention belongs to the field of food fresh-keeping products, and particularly relates to an alcohol bag for food fresh keeping and a preparation method of the alcohol bag. The alcohol fresh-keeping material comprises a front-side wrapping material, a back-side wrapping material and an alcohol fresh-keeping material body, a middle reserved cavity is formed by the front-side wrapping material and the back-side wrapping material in a peripheral hot-pressing mode, and the middle reserved cavity is filled with an alcohol fresh-keeping material body. Ventilation micropores are formed in the front surface wrapping material. Each of the front-side surface profile and the back-side surface profile consists of a high-temperature-resistant printing layer, a composite connecting layer and a heat-sealing layer; the high-temperature-resistant printing layer is an outer surface layer and is formed by any combination of PET, OPP, CPP, NY and TQPE in a co-extrusion mode, a plurality of breathable micropores are evenly formed in the high-temperature-resistant printing layer, and volatilization of alcohol is controlled through the size of the pore diameter and a matrix; the packaging film formed by extruding macromolecules ensures that alcohol is air-permeable and liquid-impermeable during volatilization, the volatilization speed can be adjusted, the situation that the taste of food is affected by overhigh local alcohol concentration is not easily caused, and meanwhile, the food can be kept fresh for a long time.

The invention discloses a preparation method of a multifunctional polyvinyl composite film and application of the multifunctional polyvinyl composite film in food preservation. The preparation method comprises the following steps: firstly, preparing Ag-coated MOF through a hydrothermal method, then uniformly dispersing the Ag-coated MOF and tannic acid into a carboxymethyl chitosan solution, and carrying out crosslinking modification on the Ag-coated MOF; and coating the prepared CMCS / TA / Ag (at) MOF mixed solution on a polyethylene film treated by oxygen plasma, and drying to form a film, so as to obtain the multifunctional polyethylene-based composite film. The CMCS and the TA are adopted to perform crosslinking modification on the Ag-coated MOF, so that the stability of the Ag-coated MOF can be further improved, and the release of silver ions is reduced. Compared with a common PE preservative film, the composite film prepared on the basis has better barrier capacity and mechanical property, and has antibacterial, anti-ultraviolet and anti-oxidation effects. The multifunctional preservative film is convenient to use and low in price, and has an important application prospect in the aspect of fresh-keeping packaging of meat products.

The invention discloses a preparation method of a silk fibroin-based electrostatic spinning composite nanofiber membrane. The preparation method comprises the following steps: S1, obtaining silk fibroin; s2, preparing silk fibroin and a modifier into a spinning solution; the modifier is one or more of carvacrol, chitosan or chitosan quaternary ammonium salt; and S3, preparing the nanofiber membrane by adopting an electrostatic spinning method. The nanofiber membrane has the advantages of high antibacterial rate, high water permeability, good biocompatibility, excellent food preservation performance and excellent biodegradability.

The utility model provides a cold fresh meat product storage warehouse, which relates to the technical field of fresh-keeping and quality-guaranteeing storage of meat products and comprises a storage box, a fan fixedly connected to the top end of the storage box, a conveying pipe connected to the output end of the fan, a heat preservation film sleeved outside the conveying pipe, and a condenser connected to one end of the conveying pipe. A first support is fixedly connected to the bottom end of the condenser, one side of the first support is fixed into the storage box, multiple sets of moving grooves are formed in the top end of the interior of the storage box, through cooperation of hooks, pull rods, moving blocks and transverse shafts, the hooks can be lifted to preset positions by pulling the pull rods, and chilled meat products can be hung conveniently; the cold fresh meat products are prevented from being stacked together, frozen together after long-time storage and inconvenient to take out and use subsequently, then the moving blocks can move at the two ends of the transverse shaft by pushing the pull rods, and the cold fresh meat products can be conveniently moved to preset positions.

The invention relates to bamboo fiber-based food fresh-keeping packaging paper and a preparation method thereof. The preparation method of the bamboo fiber-based food fresh-keeping packaging paper comprises the following steps: respectively grinding bleached sulfate tender moso bamboo fibers and moso bamboo root fibers, and dispersing and mixing to obtain NBF / BRF mixed pulp; then adding the modified moso bamboo cellulose nanocrystals to obtain NBF / BRF / BNC composite slurry; making paper with pulp, forming, dehydrating and drying to obtain a bamboo paper sample A, uniformly spraying bamboo vinegar on the outer surface of the bamboo paper sample A, and finally performing hot pressing and drying to obtain the bamboo fiber-based food fresh-keeping packaging paper. Bamboo fiber raw materials with different characteristics are used for preparing the packaging paper for food preservation, the bamboo fiber-based food packaging paper is endowed with excellent mechanical strength, barrier property, hydrophobic property and antibacterial and mildew-proof capabilities, and the bamboo fiber-based food packaging paper can be used in the field of packaging materials for fruit and vegetable preservation.

According to the antibacterial and antioxidant composite film applied to food preservation and the production method of the antibacterial and antioxidant composite film, the chlorogenic acid, the catechin, the montmorillonite and the zeolite are introduced, and a drying process is optimized, so that the antibacterial performance, the antioxidant performance and the mechanical performance of the preservative film are remarkably improved, and meanwhile, the water vapor permeability and the oxygen permeability are reduced. The method comprises the specific steps of raw material preparation, polyphenol compound and mineral substance preparation, membrane liquid preparation and treatment, drying process optimization and finished product membrane uncovering. According to the preparation method disclosed by the invention, components such as chlorogenic acid, catechin, montmorillonite and zeolite are introduced, and a drying process is optimized, so that the food preservative film with synergistic antibacterial and antioxidant properties is prepared.

The invention discloses a preparation method of ocimum gratissimum carbon dots and application of the ocimum gratissimum carbon dots in antibacterial drugs and food preservation. The preparation method of the ocimum gratissimum carbon dots comprises the following steps: performing steam distillation on ocimum gratissimum leaves to remove essential oil, drying in the shade, and crushing; adding an alcohol solvent into the powder, extracting, filtering, concentrating and drying to obtain an alcohol extract; dispersing the alcohol extract in distilled water, and stirring and pyrolyzing on a heating table; and diluting the pyrolysis product with distilled water, centrifuging, taking supernate, filtering with a filter membrane, dialyzing, and freeze-drying to obtain the carbon dots. The obtained carbon dots have a carbon dot-vesicle coexisting structure, and the average particle size is 5.732 + / -0.5 nm. The prepared ocimum gratissimum carbon dots can be applied to preparation of antibacterial drugs, especially drugs for inhibiting the activity of bacillus cereus and listeria, and the field of food preservation, and have the advantages of being wide in raw material source, simple in preparation method, low in cost, environmentally friendly and the like.

The invention belongs to the technical field of food preservation, and particularly discloses an aerogel fiber membrane with humidity response and capable of being used for food preservation and a preparation method of the aerogel fiber membrane. The preparation method comprises the following steps: mixing a shell film-forming substance with a first solvent to obtain a shell spinning solution; mixing a core layer gel substance, a biological preservative, a cross-linking agent and a second solvent to obtain a core layer gel spinning solution; and then carrying out coaxial electrostatic spinning on the obtained shell layer spinning solution and core layer gel spinning solution at 40-60% RH to obtain the aerogel fiber membrane which has humidity response and can be used for food preservation. The core layer with the porous aerogel structure is prepared in one step, preparation is simple, industrialization is easy to achieve, and good application prospects are achieved; the aerogel fiber membrane not only can solve the problem of juice seepage in the storage process of fresh food, but also can perform humidity response to the environment and intelligently release an antibacterial agent in a controlled mode, growth and reproduction of dominant putrefying bacteria in the storage process of the fresh food are inhibited, and the preservation period is prolonged.

The invention discloses an electric field fresh-keeping device, an electric field control method, a controller and refrigeration equipment, in the fresh-keeping process of food materials, under the condition that an air door is opened, a power supply is controlled to apply first voltage to a plate-shaped electrode and a needle-shaped electrode, the plate-shaped electrode provides an electric field to keep the food materials fresh, and meanwhile, the point of the needle-shaped electrode discharges to ionize air; when the air door is closed, the power supply is controlled to apply a second voltage to the plate-shaped electrode and the needle-shaped electrode, so that the food materials in the storage assembly can be sterilized and deodorized, and the electric field fresh-keeping function and the ionization sterilization function can be realized; and when the air door is closed, the power supply is controlled to apply a second voltage to the plate-shaped electrode and the needle-shaped electrode, so that the food materials can be sterilized. The plate-shaped electrode and the needle-shaped electrode provide an electric field to keep food fresh, and the electric field fresh-keeping function is achieved, so that the electric field fresh-keeping device can achieve electric field fresh-keeping and ionization sterilization through one electric field assembly, and can work in combination with the opening and closing state of the air door to achieve the effects of fresh-keeping, sterilization and odor removal.

The invention belongs to the technical field of food preservation, and particularly relates to a chitosan / polyvinyl alcohol film loaded beta-acid / beta-cyclodextrin inclusion compound as well as a preparation method and application thereof. The method comprises the following steps: adding beta-acid / beta-cyclodextrin into distilled water, grinding and centrifuging, and freeze-drying the obtained supernatant to obtain the beta-acid / beta-cyclodextrin inclusion compound. The preparation method comprises the following steps: mixing a PVA solution with a chitosan solution, adding glycerol to obtain a mixed solution, dissolving the beta-acid / beta-cyclodextrin inclusion compound in water, adding the dissolved beta-acid / beta-cyclodextrin inclusion compound into the mixed solution, stirring, standing and drying to obtain the film. The prepared film has good physical properties and stability, has good oxidation resistance and antibacterial activity, can inhibit adhesion of pathogenic microorganisms such as staphylococcus aureus on the surfaces of perishable fruits, and prolongs the shelf life of the perishable fruits.

The invention provides an edible haematococcus pluvialis residue preservative film and a preparation method thereof, and relates to the technical field of food preservation, the edible haematococcus pluvialis residue preservative film comprises 0.4%-1.6% of dry haematococcus pluvialis residue, 1%-4% of a plasticizer, 0.2%-1% of a cross-linking agent and a film matrix solution according to a mass-volume ratio; the membrane matrix solution comprises chitosan with the mass-volume ratio of 1%-3% and citric acid with the mass-volume ratio of 1%-4%. A compact network structure is formed among the components, so that the adhesion between the haematococcus pluvialis residues and the chitosan is enhanced, and haematococcus pluvialis residue particles can be effectively loaded; under the flexible network structure formed by the film matrix and the cross-linking agent, the red pluvialis ball residues are protected from being damaged in the film liquid drying process, the film is not easy to become dry and crisp and crack, and finally the soft and tough edible bio-based film is formed; the technical problem that the preservative film prepared from the haematococcus pluvialis residues is lacked in the prior art is solved.

The invention discloses an ROS-responsive edible antibacterial preservative film and a preparation method thereof. The invention discloses a ROS (reactive oxygen species)-responsive antibacterial agent which is composed of sodium alginate (SA), carboxymethyl chitosan (CS), an ROS response group (TK-NH2) and antibacterial micromolecules (AB), TK-SA with ROS response characteristics is obtained through acylation reaction of TK-NH2 and SA through EDC, the antibacterial micromolecules (AB) are loaded into TK-SA through acylation reaction of EDC, and AB-TK-SA with antibacterial activity is obtained; aB-TK-SA and CS are mixed, sprayed to a clean glass plate and dried at the room temperature. The ROS-responsive edible antibacterial preservative film (AB-TK-SA / CS) provided by the invention has the characteristics of safety, low toxicity and ROS-responsive release, and can effectively inhibit the growth of staphylococcus aureus; the method is simple and convenient in preparation process, low in cost and good in reproducibility, and has a good application prospect in the field of related food preservation.

The invention belongs to the technical field of carbon dioxide capture low-energy-consumption safe storage methods, and discloses a marine diesel engine tail gas carbon dioxide capture low-energy-consumption safe storage method which comprises a carbon dioxide capture system, a low-energy-consumption system and a safe storage system. The carbon dioxide trapping system is mainly used for separating carbon dioxide from tail gas of a marine diesel engine for subsequent sealing or utilization, the carbon dioxide trapping system is divided into a pretreatment unit and a carbon trapping unit, and the carbon dioxide can be conveniently transported and sealed through liquefaction storage; the volume of the liquefied carbon dioxide is greatly reduced, long-distance transportation and storage are facilitated, the transportation cost is reduced, the liquefied carbon dioxide can also be used as a resource, for example, the liquefied carbon dioxide can be used in the fields of industrial raw materials, refrigerants, food preservation and the like, sustainable utilization of the resource is achieved, and the energy storage mode has the advantages of low cost, high efficiency, long service life and the like. And the energy utilization efficiency can be improved.

The invention discloses a slow-release antibacterial and antioxidant composite preservative film and a preparation method thereof. The slow-release antibacterial and antioxidant composite preservative film is prepared from a chitosan matrix and Chuzhou chrysanthemum essential oil nano-emulsion loaded in the chitosan matrix, the Chuzhou chrysanthemum essential oil nano-emulsion comprises Chuzhou chrysanthemum essential oil, a surfactant and a cosurfactant, and the average particle size of the Chuzhou chrysanthemum essential oil nano-emulsion is smaller than 200 nm; the composite preservative film has the function of slowly releasing the Chuzhou chrysanthemum essential oil and shows antibacterial and antioxidant activity; the preparation method comprises the following steps: firstly preparing Chuzhou chrysanthemum essential oil into a nano-emulsion by adopting a nano-encapsulation method through a high-pressure homogenization method to form the Chuzhou chrysanthemum essential oil nano-emulsion, then embedding the Chuzhou chrysanthemum essential oil nano-emulsion into chitosan to prepare an active chitosan composite film, and finally applying the antibacterial coating material to food preservation. The antibacterial coating film not only can effectively inhibit pathogenic microorganism infection in berry storage and logistics transportation in a wider spectrum, but also can regulate physiological metabolism of picked berries, delay the senescence process and reduce loss of internal moisture.

The invention discloses pyridone endoperoxide with antibacterial and antiviral activity and application thereof, and belongs to the fields of organic compound synthesis and medical technology, food engineering and the like. The invention proves that the series of endoperoxides can effectively kill pathogenic bacteria, fungi and viruses, including propionibacterium acnes, escherichia coli, staphylococcus aureus, candida albicans, human papilloma viruses, herpes simplex viruses and the like. The internal peroxide designed by the invention has the capability of treating skin diseases, is expected to be developed into a first-line medicine for treating skin diseases caused by pathogen invasion, and mainly relates to bacterial skin diseases, fungal skin diseases and viral skin diseases caused by pathogen infection. Meanwhile, the series of endoperoxides can be used for treating oral infection, periodontitis, infection of shoulder and other joint operations, and bacterial infection such as pressure sores. In addition, the peroxides in the series can also be used in the fields of food preservation, disinfectant preparation and the like.

The invention discloses a rapid food preservation control method based on a flash freezing technology, and relates to the technical field of food preservation, and the method comprises the following steps: obtaining first data of food, and spraying a nano coating containing antifreeze proteins with different concentrations on the surface of the food; inputting the first data into a pre-trained neural network model to obtain second data; according to the second data, a refrigerant injection device and a pulse electric field excitation device are synchronously started, food dynamic data are obtained, feature extraction and trend prediction are conducted on the food dynamic data, and the food dynamic data comprise the real-time core temperature and the ice crystal formation dynamic state; according to the prediction result, the refrigerant flow rate and the electric field frequency are dynamically adjusted, and the release rate of antifreeze protein in the nano-coating is synchronously adjusted; according to the method, the refrigerant flow rate, the electric field frequency and the antifreeze protein release rate are accurately and synchronously adjusted, so that the problems of non-uniform freezing, overlarge ice crystals and food quality deterioration in a traditional freezing method are effectively solved, and the food freezing fineness and the fresh-keeping effect are improved.

The invention relates to an electric field regulation and control preservation method and device for a ship partner refrigeration house and a storage medium, and relates to the technical field of refrigeration house preservation based on an electric field, and the method comprises the steps that S1, a set working mode is received; s2, searching a corresponding electric field intensity reference value and an electric field uniformity threshold value according to a set working mode; s3, acquiring each electric field intensity sensor in real time; s4, the maximum electric field intensity error and the average electric field change rate are calculated based on the collected electric field intensity values, and comprehensive uniformity parameters are obtained through calculation in combination with the electric field intensity reference value; s5, judging whether the comprehensive uniformity parameter is lower than an electric field uniformity threshold value or not, and if yes, executing the step S6; and S6, working parameters of the electric field generator are adjusted according to the maximum electric field intensity error and the average electric field change rate. Compared with the prior art, the food fresh-keeping device can effectively solve the problem that the food fresh-keeping effect is poor due to uneven electric field distribution caused by long-term wave swinging.

The invention discloses a lactobacillus johnsonii and related products and applications thereof, and relates to the field of microorganisms. The Lactobacillus johnsonii GJ231 provided by the invention has a preservation number of CCTCC NO: M 2023981. Compared with other lactobacillus johnsonii, GJ231 is acid-resistant and bile-resistant, has a higher survival rate in the intestine, has a better antibacterial effect on a variety of pathogens, and can be used to prevent and treat related diseases caused by pathogens; secondly, GJ231 has a better high temperature tolerance and has a higher survival rate in the process of spraying and preparing pet food; furthermore, GJ231 also has a strong antioxidant capacity, can reduce the peroxidation reaction caused by oxidative stress, and can be used for anti-aging and anti-oxidation; in addition, GJ231 also has a bacteriocin gene cluster, which may be used to produce bacteriocin, and has the potential to replace antibiotics and food preservation.

The invention provides a long-acting antibacterial / antioxidant biomass-based essential oil microcapsule and a preparation method thereof. The preparation method comprises the following steps: firstly, uniformly stirring and mixing a chitosan stock solution and a casein stock solution, adjusting the pH value of a mixed system, and promoting the formation of nanoparticles through reverse charge neutralization of casein and chitosan; centrifuging the mixed solution, collecting a supernatant, slowly dripping essential oil into the supernatant, stirring and emulsifying, and ultrasonically preparing an emulsion; and finally, adding a natural cross-linking agent for cross-linking, and filtering and drying after reaction to obtain the long-acting antibacterial / antioxidant biomass-based essential oil capsule. The method does not need an additional emulsifier, is simple in process and low in cost, and is suitable for the fields of drug delivery, cosmetics and food preservation. The prepared microcapsule has the advantages of better stability, high coating rate, good slow release performance, long-acting antibacterial / antioxidant property and the like.

The invention discloses a chitosan-based preservative film with a pH colorimetric function as well as a preparation method and application of the chitosan-based preservative film. The chitosan-based preservative film is prepared from the following preparation raw materials: chitosan, cellulose nanofibers, a deep eutectic solvent and a beet red-zinc ion complex. Wherein the chitosan enables the film to have antibacterial property; the cellulose nanofiber can enhance the tensile strength and toughness and reduce the water vapor / oxygen permeation coefficient; the beet red-zinc ion complex has the characteristic of more stable color development, and the color difference response delta E to pH 2-12 is greater than or equal to 8. The chitosan-based preservative film disclosed by the invention can be applied to food fresh-keeping packaging and food freshness monitoring; the preservative film disclosed by the invention can be used for effectively prolonging the service life of fruits and vegetables while ensuring the food safety; in food freshness monitoring application, the preservative film changes from low-pH-value orange to high-pH-value yellow according to the change of acid-base conditions, and the preservative film can be used as a pH colorimetric sensing film for freshness monitoring.

The invention relates to a chitosan / corn starch slow-release antibacterial and antioxidant multifunctional composite preservative film and a preparation method, and belongs to the technical field of food preservation. The invention relates to a chitosan / corn starch slow-release antibacterial and antioxidant multifunctional composite preservative film and a preparation method thereof. The preparation method comprises the following steps: firstly, respectively preparing an acetic acid aqueous solution of chitosan and a gelatinized corn starch solution by taking chitosan and corn starch as main raw materials, uniformly mixing the two solutions, then adding a cross-linking agent, carrying out a cross-linking reaction at a certain temperature to obtain a chitosan / corn starch cross-linking solution, and then adsorbing an antibacterial antioxidant into a porous corn starch slow-release carrier; then uniformly dispersing the chitosan / starch cross-linking solution, and then adding a plasticizer to prepare a film forming solution; finally, the chitosan / corn starch multifunctional composite fresh-keeping film is obtained by adopting a vacuum-pumping defoaming and drying film-forming method in sequence. The prepared preservative film has the advantages of being excellent in slow release performance, antibacterial and antioxidant performance and mechanical performance, simple in preparation process and the like, use of chemical preservatives is avoided, the green and environment-friendly concept is met, and good application prospects are achieved.

The invention belongs to the technical field of biological application, and particularly relates to lactobacillus paracasei GY1 as well as a screening method and application thereof. The lactobacillus paracasei is lactobacillus paracasei GY1 separated and screened from mulberry soil samples, the preservation number is CGMCC No.30931, and the lactobacillus paracasei is classified and named as lactobacillus paracasei in China General Microbiological Culture Collection Center on June 11, 2024, and the preservation number is CGMCC No.30931; the strain is a safe strain with good probiotic potential, and the nucleotide sequence of 16S rDNA sequencing of the strain is as shown in SEQ ID NO. 1. By optimizing the culture conditions of the screened strains, the bacteriostasis rate of the obtained supernate on staphylococcus aureus is higher than 95%, a new thought is provided for the field of food preservation of dairy products and the like, and good market prospects are achieved.

The invention belongs to the technical field of high polymer materials, and particularly relates to a high-strength plastic film and a preparation method thereof. The high-strength plastic film is prepared from the following raw materials in parts by weight: 80 to 90 parts of polylactic acid, 5 to 10 parts of polyurethane resin, 2 to 6 parts of flame-retardant modified halloysite, 2 to 6 parts of antioxidant modified halloysite, 0.5 to 2 parts of silane coupling agent and 1 to 3 parts of plasticizer. According to the invention, the halloysite is subjected to flame-retardant modification and antioxidant modification and is added into a PLA matrix, so that the halloysite can be used as an inorganic filler to reinforce the rigidity and strength of the PLA matrix, and also has flame-retardant and antioxidant dual functions; meanwhile, the tubular structure of the halloysite nanotube can form a zigzag path in a PLA matrix, so that diffusion of water vapor and oxygen is delayed, the water vapor permeation amount and the oxygen permeation coefficient are reduced, and the halloysite nanotube can be applied to food packaging to prolong the fresh-keeping period of food.

The invention discloses a carbon quantum dot-polyvinyl alcohol composite film and a preparation method thereof, and belongs to the technical field of food packaging fresh-keeping materials. The composite film is prepared by taking apocynum venetum carbon quantum dots and polyvinyl alcohol as raw materials under the action of a plasticizer, wherein the apocynum venetum carbon quantum dots are prepared from apocynum venetum fiber powder, dithiosalicylic acid and urea through a hydrothermal method. The composite film provided by the invention has excellent ultraviolet shielding, pH-responsive fluorescence discoloration, antibacterial and antioxidant properties, and can realize visual monitoring of the freshness of high-protein food. The preparation method disclosed by the invention is simple in process, environment-friendly, suitable for the field of food active packaging and wide in application prospect.

The invention discloses a degradable antibacterial preservative film with medicinal and edible extracts as well as a preparation method and application of the degradable antibacterial preservative film, and belongs to the technical field of preservative films. The method comprises the following steps: (1) dissolving chitosan in an acetic acid aqueous solution, adding a wormwood extract into the obtained chitosan solution, and stirring at a certain temperature to form a mixed solution; (2) adding potato starch into water to prepare a potato starch solution; gelatinizing the potato starch solution, adding glycerol into the gelatinized solution at a certain temperature, and stirring to obtain potato starch gelatinized solution; (3) mixing the mixed solution and the potato starch gelatinization solution according to a certain proportion, pouring the mixture to a polytetrafluoroethylene substrate, and drying to form a film, so as to obtain the degradable antibacterial preservative film. The method has the advantages of being convenient in process, wide in raw material source and suitable for large-scale production. The prepared degradable antibacterial preservative film has excellent biodegradability, preservation performance and oxidation resistance, and has a wide application prospect in the field of food preservation.