The potential application of red cabbage indicator film as smart packaging on tuna fillet

Edible chitosan film was used as a carrier for red cabbage pigment extract and then formed into a 2 x 2 cm smart indicator. The solvent extraction process in this study used 96 percent ethanol and a maceration-sonication method. Sensitivity indicators were evaluated on tuna fillet samples wrapped in plastic with the parameters of the analysis. This included determining the number of TVBN, TMA, and TPC as well as discoloration during testing at freezer (-6°C), cool temperature (10°C), and room temperature (28°C). The results indicated that visually smart discoloration indicator transitioned from early purple to blue to green. At freezer temperature (- 6°C), the discoloration smart indicator takes 365 hours to transition from purple to green, compared to 149 hours at cool temperature (10°C) and 31 hours at room temperature (28°C). Discoloration of smart indicators occurs during storage at each temperature, which increases the value of TVBN, TMA, and TPC. The smart indicator pigmented red cabbage product has an excellent sensitivity, with a purple plot representing the condition of packaged fresh ingredients, blue (fit for consumption), and green (not fit for consumption).