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A water-soluble chitosan hydrogel, carboxymethyl chitosan/oxidized carboxymethylcellulose/curcumin (CMCHS/OCMC/CR) ternary composite, was prepared by the casting method. FTIR and SEM showed that the cross-section structure of the composite film was uniform without stratification, but the surface roughness was higher than that of the CMCHS/OCMC film. Compared to the film with no curcumin, CMCHS/OCMC/CR showed better fracture stress (20.10 MPa), elongation at break (18.97%), anti-fungal properties (Aspergillus niger inhibition zone 15.33 mm, Penicillium inhibition zone 14.58 mm), and water vapor permeability (2.11x10-3 g⋅m-1 ⋅kPa-1 ⋅h-1). The film-coating experiments indicated that coating with CMCHS/OCMC/CR composite could effectively decelerate the weight loss as well as the decrease in titratable acid, soluble solids, and reducing sugar contents in strawberry during storage.After storage for eight days, the weight loss rate of strawberry in the CMCHS/OCMC/CR group decreased by 11.38% and 1.27%compared to those in the blank and positive control groups. Moreover, the hardness, titratable acid, soluble solids, and reducing sugar of strawberry in the CMCHS/OCMC/CR group decreased by 10.00%, 42.72%, 7.39%, and 9.32% compared to the blank control and by 5.54%, 7.42%, 2.39% and 11.12% compared to the positive control, respectively. Therefore, the CMCHS/OCMC/CR (1%, m/m) composite film showed good preservative effects of color preservation and inhibition of mold growth and could be used as an effective antibacterial coatingmaterial in food packagingmaterials. [ABSTRACT FROM AUTHOR]

A PDMS/PVDF pervaporation composite membrane was self-made via the coating method and used for separating volatile aromatic compounds from the waste liquid of lemon essential oil processing by pervaporation (PV). The PDMS/PVDF membrane was applied in the pervaporation separation of nerol, α-terpineol, and linalool, which are characteristic aroma components in lemon essential oil waste liquid. The results demonstrated that the PDMS/PVDF membrane had good separation selectivity for the three compounds, but the permeation flux was low. Addition of ethanol significantly affects the separation of aromatics. When the amount of ethanol added is 5% v/v, the permeation fluxes of nerol and linalool increase by 82.93% and 127.76% over those without ethanol. The permeation flux of α-terpineol first increased and then decreased slowly with the increase in ethanol concentration. In addition, the performance of the PDMS/PVDF membrane in separating volatile aroma components in actual lemon oil waste liquid was tested. When the experiment was conducted for 6 h, the types and content of volatile aromatic compounds in the lemon oil waste liquid were significantly reduced. The recovery rates of nerol, α-terpineol, and linalool were 92.50%, 93.37%, and 60.36% respectively. The results showed that the PDMS/PVDF membrane achieved better performance. Keywords: lemon oil processing waster liquid; volatile aromatic components; pervaporation; separation perfomance; synergistic effect of ethanol [ABSTRACT FROM AUTHOR]