Preparation Of Intelligent Gas Phase Controlled Release Antioxidant Composite Film Based On Microcapsules And Temperature Sensitive Liposomes

Oxidate is an important factor affecting food deterioration.In recent years,anti-oxidant activity packaging films have become more and more research due to their ability to effectively release antioxidants.However,how to achieve slow-release regulation of antioxidants is one of the key issues that the engineering community pays attention to.Therefore,combining the release of antioxidants with the external environmental factors of the packaging to prepare smart-responsive packaging films has important application significance.In this paper,the idea of introducing temperature-sensitive substances into the non-temperature-sensitive film is used to prepare temperature-controlled release films.The temperature-sensitive liposome(t-L)is used as the carrier to coat the natural antioxidant rosemary essential oil(REO)to give the film the characteristics of temperature-controlled release of antioxidants.In order to make the film have both temperature-controlled release and long-lasting slow-release performance,porous starch is used to absorb natural antioxidant lemon essential oil(LEO),and powdered essential oil is used as the core material and ?-cyclodextrin(?-CD)is used for secondary encapsulation to prepare LEO.Microcapsules give the film long-term oxidation resistance.The high-barrier material BOPP is used as the base film,combined with the chitosan and pullulan compound film added with liposomes and microcapsules to prepare an antioxidant composite film.And research the mechanical properties and release properties of the film.The research content and research results are as follows:(1)Preparation and performance study of t-L.Optimize the preparation process of t-L through single factor experiment and orthogonal experiment,and study freeze-drying process to improve storage performance.At the same time verify the other properties of liposomes and temperature control release characteristics.The results show that the optimal preparation process parameters of REO t-L are: membrane material ratio 20 wt%,lipid-drug ratio 10 wt%,PBS buffer temperature 32 ?.The optimal freeze-drying process is a freeze-drying process with 9% concentration of anhydrous lactose and a longer pre-freezing time.The encapsulation rate of t-L is 66.02%,the morphology is irregular spherical vesicles,the particle size distribution is between 150 nm?200 nm,and the dispersion is good.It has two phase transition temperatures of 38.5 ? and 41.8 ?,the main temperature control range is 39 ??42 ?.Under the condition of 42 ?,the release of REO in liposomes reached 78.1% within 1 h,which has remarkable temperature-controlled release performance.There is no significant change in various indicators during the 60 days storage period at 4 ?,and the stability is good.(2)Preparation and performance study of microcapsules.Determine the optimal preparation process of microcapsules through single factor experiment and orthogonal experiment.Study the morphology and thermal stability of the microcapsules to verify their sustained release characteristics.The results show that the optimal ratio of LEO to porous starch is 1:3,and the optimal process parameters of microcapsules are: core-to-wall ratio 10wt%,encapsulation temperature 45 ?,and encapsulation time 5 h.The encapsulation rate of microcapsules is 65.01%,Under SEM observation,the shape is regular and the dispersion is good,and the particle size distribution is about 5 ?m?10 ?m.The microcapsules have good thermal stability and strong antioxidant activity.The release rate of LEO in the microcapsules increased with the increase of temperature,and the release amount was 59.1% within 7 days under the condition of 50 ?.(3)Preparation and performance study of intelligent antioxidant packaging film.Optimize the preparation process of polysaccharide membrane through single factor test and response surface analysis,and to study the composite process of basement membrane and polysaccharide membrane.Verify the temperature-controlled release and long-term sustained release performance of antioxidants in the antioxidant composite film.The results show that the addition of pullulan,the addition of liposomes and the addition of microcapsules all have significant effects on the mechanical properties of the polysaccharide membrane.The optimal preparation process parameters of the polysaccharide membrane optimized by response surface analysis were: 34.31 wt% pullulan,0.92 wt% liposomes,0.91 wt% microcapsules.The best composite process of polysaccharide film and BOPP is direct coating after corona treatment with a parameter of30,and the composite effect is good.The anti-oxidation composite film has excellent temperature control release performance.The antioxidant REO can be released quickly in the range of 39 ??42 ?,and the release of REO reaches 94.1% in 7 days under the condition of 42 ?.And the film has excellent slow-release performance for LEO,the higher the temperature,the faster the release.The release rate gradually stabilized on the 4th day and thereafter,with a significant slow-release effect.