Effect of HLB value on the properties of chitosan/zein/lemon essential oil film‐forming emulsion and composite film

Summary The properties of film‐forming emulsion with emulsifiers of different hydrophilic–lipophilic balance were evaluated, and the performance of chitosan/zein composite film containing lemon essential oil was examined. The retention ratio of lemon essential oil in the film and the release of lemon essential oil from film to food simulation system were also quantitatively analysed. Results showed that the emulsifier with higher hydrophilic–lipophilic balance would make lemon essential oil disperse evenly in the film‐forming emulsion, leading to smaller particle size and a lower viscosity of emulsion. Compared with C/Z/L, with the increasing hydrophilic–lipophilic balance value of emulsifier, the tensile strength and water contact angle of films decreased to 28.06 MPa and 23.39°, respectively. Emulsifier with high hydrophilic–lipophilic balance value could effectively increase the initial retention ratio of essential oils in the film, and the maximum initial retention rate of the C/Z/L‐15 film was 79.12%. The release of lemon essential oil in each treatment increased rapidly at first and then it slowed down. C/Z/L‐15 had the highest retention rate after 12 days, and C/Z/L‐11 had the best sustained release effect when lemon essential oil was released into the food simulant.