Smart film of jackfruit seed starch as a potential indicator of fish freshness

Abstract Smart film from jackfruit seeds containing anthocyanin extract has potential application as a freshness indicator of fish as they deteriorate, changing the color as a function of the product pH. The lower solubility percentage of the films was evidenced by the lower anthocyanin extract volume. The films presented mean water vapour permeability values of 3.034 g.mm/kPa.h.m2. The starch/anthocyanin film (ST4.0:AN5.0) showed higher tensile strength, while ST2.4:AN5.0 and ST3.0:AN5.3 showed lower resistance. A small change in color in the films was evidenced after 48 hours, and fish (FF10) presented a blue color after 146 hours with a reduction in a* values. Shrimp (SF10) presented negative b* values and grayish color. The indicator film provides an alternative for a convenient, non-destructive and easy-to-view method, as well as informing consumers about the quality of the packaged product. The indicator function of the film was positive, suggesting the potential use of industry co-products in developing smart food freshness indicator packaging.