Chitosan–corn starch films with sporopollenin as natural reinforcing cum encapsulating agent for postharvest preservation of sapodilla
摘要
Active packaging using bioactive compounds loaded edible polymers is an emerging concept to maintain food quality and safety with increase in shelf life. Therefore, an active edible films/coatings of chitosan blended with corn starch (CTS/CS) were developed. CTS/CS films were further fortified with bioactive compounds extracted from pomegranate peels (PP) and encapsulated within sporopollenin (SP) derived from Lycopodium clavatum spores (CTS/CS/SP) to enhance antioxidants and antimicrobial properties. SP played dual role as effective natural filler for CTS/CS film matrix due to its uniform size, bio-compatibility, high thermal stability, biodegradability, and nontoxicity as well as encapsulating agent for the bioactives from PP. CTS/CS/SP film matrix containing bioactive compounds from PP (CC-A) depicted good light barrier properties, tensile strength of 16.46 MPa with 78.5% elongation, and could reduce the water vapor transmission rate (10.06 ± 0.88 gm2/h) as compared to the control (CC) as well as film without bioactive compounds (CC-NA). FTIR analysis confirmed successful interaction between the functional groups of polymers/SP/PP. The film forming solutions were used to coat sapodilla and its shelf-life was evaluated at a regular interval up to 12 days at 25 ± 2°C. The sapodilla coated with CC-A coating depicted enhanced shelf-life, as confirmed by various parameters like weight loss, decay %, total soluble solid (TSS) content, respiration rate, high total phenolic content, and ascorbic acid value as compared to control sample at the end of storage period. These innovative films/coatings can be used as compostable films and coatings, in turn demonstrating the potential to balance functionality with environmental sustainability.