Construction and intelligent monitoring performance of freshness indicator packaging films

In order to prolong the shelf life of products and intelligently monitor their quality changes, a series of freshness indicator packaging films were prepared via casting method using cassava starch dual-modified by acetylation and phosphorylation as raw material and anthocyanin as color indicator. The interactive influence of cassava starch type, cassava starch mass concentration, glycerin content and anthocyanin concentrate content on the physical, mechanical and water vapor barrier properties of packaging films were analyzed by orthogonal experiments, followed by evaluation on the intelligent color response characteristics of the optimal film for fish fillets packaging. The results showed that when the mass concentration of acetylated distarch phosphate was 40 g/L, the glycerol content was 30% (based on the mass of acetylated distarch phosphate, the same below), and the anthocyanin concentrate content was 30% (based on the mass of acetylated distarch phosphate, the same below), the packaging film (S1 film) obtained exhibited optimal comprehensive performance, the transparency, hydrophobicity, water vapor barrier capacity and tensile strength of S1 film was 1.08 mm–1, 86.32◦, 1.19×10–10 g/(m.s.Pa) and 14.23 MPa, respectively, in comparison to those of natural cassava starch film. The S1 film displayed pink, purple and yellow-green in acidic, neutral and alkaline environments, respectively, and was sensitive to the ammonia gas. The color change of S1 film could indicate the freshness level of fish fillets. © 2023 Fine Chemicals. All rights reserved.