Preparation And Application Of Chitosan-Based Edible Packaging Film

With the development of science and technology,people's living standards are increasing,so the functional requirements for food packaging materials are also increasing.Traditional plastic packaging has been increasingly questioned because of its difficulty in degrading,wasting resources,and possibly causing harm to humans.Therefore,the use of pure natural materials to prepare degradable and even edible cling film has become the direction of many researchers.The edible fresh-keeping film prepared at the current stage,although complete in functionality and good in nature,has a low yield.This is because there are still a series of problems in the actual production of edible film formulations at this stage.In this paper,chitosan was used as a film-forming raw material,and different auxiliaries were added for blending modification to optimize the properties of the film.The film-forming process and formula were optimized through single-factor experiments and response surface tests,and were characterized by Means were used to characterize the intermolecular interaction and thermal stability of the film.In the intermediate test,the film can be smoothly produced as a standard,and additives are used to modify it to ensure its normal production and study its practical application effect.(1)Preparation and characterization of chitosan/soy protein edible packaging film.The concentration of the chitosan solution is 4%,the added amount of soybean protein is 8g,and the added amount of glycerin is 6g.The film performance is the best.At this time,the thickness of the chitosan-soy protein edible film is 0.098mm,and the tensile strength is7.51MPa,The elongation at break is 16.3%,the light transmittance is41.1%,and the air permeability is 0.0019?m/(Pa·S).And analyzed by scanning electron microscope,infrared spectroscopy and differential scanning calorimetry:the addition of soy protein improved the brittleness of the chitosan film,repaired the cracks on the surface of the chitosan film,but reduced the toughness and Thermal stability.(2)Preparation and characterization of chitosan/sodium alginate edible packaging film.The film formulation and process parameters were optimized through single factor and response surface tests.It was concluded that when the chitosan content was 7.34 g,sodium alginate content was 7.00 g,and glycerin content was 5.25 g,the film tensile strength was 23.72 MPa,The elongation at break is 41.1%,the water solubility is 76.6%,the air permeability is 0.0017?m/(Pa·s),and the water vapor transmission rate is 1.61 g·mm/m~2h·KPa.Scanning electron microscopy,infrared spectroscopy,and differential scanning calorimetry analysis revealed that the molecular cross-linking between chitosan and sodium alginate is good,and the addition of sodium alginate improves the mechanical properties,barrier properties,Thermal stability and water solubility.(3)Study on the peeling performance of edible packaging film of chitosan/sodium alginate.Food emulsifiers such as potassium stearate,mono-bis-stearate,and sucrose fatty acid esters were selected as release agents.The effects of their concentrations on film peeling performance were studied,and the effects of food emulsifiers on film machinery were discussed.Impact of performance and barrier properties.The results show that when potassium stearate is selected as the release agent and its concentration in the film solution is 0.2%,the comprehensive properties of the film are the best.At this time,the tensile strength of the film is20.7MPa and the elongation at break is 54.5%.The water vapor transmission rate is 1.51 g·mm/m~2h·KPa,and the complete film peeling rate is 95%.(4)Application research of chitosan-based edible packaging film in instant noodle seasoning package.The prepared chitosan/sodium alginate edible packaging film was selected as the packaging material for instant noodle seasoning bags.The morphological changes,hygroscopicity,and cooking properties of the edible instant noodle seasoning bags during the packaging process were studied.The results show that the edible instant noodle seasoning package should be protected from high humidity and high temperature.Its properties are stable under normal temperature and airtight conditions,and its packaging effect is good.It has certain feasibility as an instant noodle seasoning bag,but the packaging effect is still far behind traditional packaging.