Preparation And Properties Of Resveratrol Nanoparticle Gelatin Composite Film

In recent years,with the improvement of people’s living standard,the awareness of food safety and environmental friendliness is also gradually strengthened.This puts forward higher requirements for the current food packaging materials,so the environment-friendly active packaging materials emerge as The Times require,and become a hot topic of current research.With gelatin as the membrane material,this study used wheat gliadin and sodium alginate composite particles embedding chemical instability but has antibacterial,antioxidant function of resveratrol,gelatin composite membrane is prepared not only overcome the single shortcomings brittle,and poor toughness of gelatin film also has a slow release,biodegradable,stability and other excellent performance.The application of compound gelatine film as packaging material in chicken storage has important research value and significance.The specific research contents and conclusions are as follows:1.Preparation process optimization and stability study of wheat gliadin nanoparticlesWheat gliadin nanoparticles were prepared by inverse solvent method.Firstly,four single factors in the preparation process were determined as stirring temperature,stirring speed,p H value of dispersed liquid system and ratio of wheat gliadin to deionized water on the grain size,zeta-potential and dispersion index（PDI）of wheat gliadin nanoparticles,and the particle size and dispersion index（PDI）were used as evaluation indexes.The optimum preparation conditions were determined as follows:stirring temperature 24℃,stirring rate 660 r/min,p H 5.0 of dispersed liquid system,wheat gliadin/deionized water =1:19.Due to the poor stability of wheat gliadin nanoparticles,sodium alginate was added to form a stable complex with them.The interaction between wheat gliadin and sodium alginate was analyzed by turbidity curve and Zeta-potential curve,and the ratio of wheat gliadin to sodium alginate was determined as 1:0.8（W/W）.2.Study on the encapsulation of resveratrol by wheat gliadin-sodium alginate composite particlesThe effects of particle size,ζ-potential,PDI and embedding rate on the ratio of resveratrol to wheat gliadin were studied by loading resveratrol with wheat gliadin and sodium alginate composite particles.When resveratrol: wheat gliadin =1:20,the particle size is about 304.6nm,the potential is about-38.1m V,and the PDI is about0.182,showing good stability and the maximum embedding rate is 56.74%.The stability of resveratrol: wheat gliadin =5:1~30:1 nanoparticles dispersion system to p H,salt ions,heat treatment and storage was investigated.At p H4.0~7.0,the nanoparticles remained stable,and showed tolerance to salt ion concentration less than 120mmol/L.There was no aggregation and dissociation at 30~70℃water bath heating for 30 min,and no obvious change in particle size and potential after storage at room temperature for 16 d.The retention rate of resveratrol in the embedding group was improved and the addition of sodium alginate could further protect resveratrol from decomposition.3.Preparation and properties of resveratrol nanoparticle gelatin composite membraneThe gliadin-SA /Res nanoparticles were added into the gelatin membrane solution to construct gliadin-SA /Res nanoparticles gelatin membrane.Explores the addition ratio of gelatin,glycerin and resveratrol nanoparticle addition amount of gelatin composite film tensile strength,elongation at break,oxygen through the performance and the influence of water vapor through performance,through the principal component analysis and response surface optimization,finally determines the amount of gelatin added 7%,glycerol 29%,nanoparticle content 40%.The optimum gelatine composite films were characterized and analyzed by scanning electron microscopy and infrared spectroscopy.4.Application of resveratrol nanoparticle gelatin composite membrane propertiesGliadin-SA/Res nanoparticle gelatin composite film was applied in chicken preservation process.The effects of single gelatin film（Gel）,wheat gliadin nanoparticles coated with resveratrol gelatin complex film（Gel-GRe）and wheat gliadin and sodium alginate loaded with resveratrol nanoparticles complex film（Gel-GSRe）on volatile base nitrogen,p H,color change and total colony count of chicken during storage period were compared.The antioxidant and bacteriostatic properties were also determined.The results showed that Gel-GRe and Gel-GRe groups extended the shelf life 4~6 days and had antibacterial and antioxidant properties.