Development of intelligent packaging film from soft- gel capsule waste and sago flour incorporated with red cabbage (brassica oleracea) leaves waste extract / Nur Assyiqah Syuhada Mohamad Asri

Visual pH indicator film is one of intelligent packaging system which had introduced to provide the information on the food product condition based on its colour changes. This study aims to develop a new intelligent packaging film from soft-gel capsule waste and sago flour incorporated with Red cabbage {Brassica oleracea) leaves extract. For raw materials characterization, the source of gelatin, starch, glycerol and anthocyanin compound were detected from the purified soft-gel capsule (PSC), sago flour (SF) and red cabbage leaves waste extract (RCE) by using the FTIR analysis. The thermogravimetric analysis was performed to identify the suitable heating temperature for PSC and SF which does not exceed 118.15°C and 193.26°C. During film formulation, the central composite design (CCD) was employed to determine the effect of PSC and SF concentration with a fixed concentration of RCE on the thickness (mm), tensile strength (MPa), elongation at break (%) and Young's modulus (MPa) of the film. The film with 0.263 g/ml of PSC and 0.02 g/ml of SF was chosen as the optimum formulation by considering the maximum tensile strength and elongation at break of the film by using Response Surface Methodology (RSM) software. For characterization of the film, the possible molecular interaction between film components after film development was studied by FTIR analysis. The addition of RCE to the film significantly reduced the water vapour permeability of the film from 12.241 g/m2.day to 9.793 g/m2.day. The film with RCE exhibited colour variation from red to green colour after immersion in different pH buffer and have visually perceptible by having the value of AE greater than 1. Other than that, the RCE also improved the antioxidant properties of the film by increasing the phenolic content of the film from 0.496±0.1766 to 2.19±0.5361 ug of GA/g and increased the percentage of DPPH scavenging activity from 8.17±1.1623% to 88.78±0.8271%. The extract from red cabbage leave waste also makes the film performed as an antimicrobial property by exhibit the intermediate response of E.coli bacteria towards the film after 24 hours of culture. Therefore, the film based on food-grade by-products from pharmaceutical and agricultural industries has the potential to be used for the development of low-cost intelligent packaging film and applicable for determining the bean sprout spoilag