Controllable Construction And Antibacterial Activity Of Rapeseed Protein Janus Particle Based On Pickering Emulsion Polymerization

Janus particles are anisotropic asymmetric particles with interface stability,bacteriostasis,and controlled release of active substances,which have broad application prospects.However,how to effectively control the microstructure of Janus particles during batch construction,and the structure-activity relationship between the microstructure of Janus particles and their preservation effect in the food field remains unclear.In this paper,rapeseed protein was used as raw material to prepare ARPI nanogel through heat induction,which was used to stabilize the Pickering emulsion.Based on Pickering emulsion polymerization,Janus particle batch-controlled construction was realized,and the effect of its anisotropy on the preservation effect of perishable fruits was studied.The research contents and results are as follows:1.Stability and potential capability of Pickering emulsion prepared based on rapeseed protein nanogel: Pickering emulsion was prepared with ARPI nanogel as a stabilizer.The formation factors and stability of ARPI nanogel based Pickering emulsion were analyzed employing contact angle,particle size,PDI,CLSM,and other characterization methods.The results showed that the contact angle of ARPI nanogels was 86.7°,showing good amphiphilicity.When the concentration of ARPI nanogels was 0.75% and the oil phase fraction was 0.3,the Pickering emulsion had the highest stability,showing a good potential for long-term storage.ARPI nanogels were irregularly distributed on the surface of polymerized particles,forming asymmetric particles.2.Batch-controlled construction of rapeseed protein nanogel-based Janus particles: Based on Pickering emulsion polymerization and using ARPI nanogel as a stabilizer,the effects of different construction conditions on Janus particle size and anisotropy(JB value)were studied by FESEM,contact angle,and other characterization methods.The results showed that the number and coverage of ARPI nanogels crosslinked on the surface of the polymerized particles could be adjusted from 12 and 3% to 61 and 62%,respectively,by changing the p H of the polymerization solution,the ionic strength,and the concentration of nanogels.The JB value changed significantly from 0.78 to 1.76.The change of construction conditions can change the particle size from micron to nanometer.3.Application of rapeseed pro tein nanogel-based Janus particles in the preservation of perishable fruits: Three kinds of Janus particles with different JB values were selected to spray strawberry and banana,and the preservation effect of Janus particles was evaluated by studying weight loss rate,hardness,and other indicators.The results showed that the fresh-keeping effect of Janus particles was related to JB value.JB=0.95 had the best fresh-keeping effect.The weight loss rate of strawberry and banana decreased by about 2 times,hardness increased by nearly 2.5times and 5 times,respectively.Janus mainly inhibited the growth of Ascomycota in strawberries,but had little effect on bacterial.In conclusion,Pickering emulsion prepared with ARPI nanogel as stabilizer has good stability and the ability to construct anisotropic Janus particles.By adjusting the construction conditions,the batch-controlled construction of Janus particles can be realized,which has a significant fresh-keeping effect on perishable fruits.It provides technical support for Janus particle preparation of active packaging materials.