牛至精油Pickering乳液/纳米纤维素/果胶抗菌涂层构建及其在芒果保鲜中的应用OA

To improve the compatibility of hydrophilic polysaccharide substrates with oregano essential oil(OEO),an OEO Pickering emulsion stabilized by lauric acid-modified cellulose nanocrystals was prepared and incorporated into a cellulose nanofiber/pectin matrix to develop a mango preservation coating.The emulsion prepared at a 0.45:1 absolutely dry mass ratio between lauric acid and cellulose nanocrystals and a cellulose nanocrystal mass fraction of 1.5%showed uniform droplet size distribution and the emulsification index reached 93.7%after 48 h,reflecting good stability.The Pickering emulsion greatly affected the coating's microstructure,thereby regulating its barrier performance.The composite coating with 1.5%emulsion loading exhibited the best performance with an oxygen transmission rate of 13.25 cm3/(m2·d),a water vapor permeability of 2.59×10-13 g·cm/(cm2·s·Pa),a water contact angle of 76.03°,and 99.69%inhibition against Escherichia coli.In mango preservation trials,the coating reduced the respiratory peak by 14.41%,decreased the mass loss by 3.3%when compared with the control group on day 9 of storage,delayed the browning incidence and the reduction in firmness,and extended the shelf life by over 3 days.In conclusion,the modified cellulose nanocrystals-stabilized Pickering emulsion/nanocellulose/pectin composite coating shows enhanced gas/moisture barrier properties and antimicrobial activity,thereby maintaining postharvest mango quality.It provides an eco-friendly solution for fruit preservation.