Chitosan powder coating, a novel simple technique for enhancement of shelf life quality of carrot shreds stored in macro perforated LDPE packs

Abstract

Abstract Efficacy of an innovative powder coating technique based on chitosan, a biopolymer, with and without citric acid pretreatment (CACH and CH, respectively) was evaluated for quality maintenance of shredded carrots. Chitosan coating alone and in combination with citric acid pretreatment were found to be beneficial in reducing weight loss and resulted in minimal changes in pH, titrable acidity and total soluble solid content and exhibited lower respiration rate on storage. Total phenolic content and reducing power of chitosan coated samples were higher compared to control, indicating antioxidant activity of chitosan. β-carotene was found to be better retained in CACH treated samples, whereas, CH treated samples showed better retention of vitamin C. Chitosan treated samples were also characterized by better colour retention, superior sensory and microbial quality after 10 days of storage compared to control which was acceptable only till the 5th day of storage at 10 °C. Industrial relevance Minimally processed carrots are a growing segment in the food retail industry. However, their high perishable nature necessitates a good preservation strategy. The study has demonstrated the viability of using powder coating in combination with macro perforation as a simpler, quicker and cost-effective technique, as against the conventional coating techniques for extending shelf life of carrot shreds. The study further confirms the ability of chitosan, an environmental friendly biopolymer produced largely from industry waste, for improving the shelf life quality and health potential of fresh cut produce. The above preservation strategy also has high commercial feasibility.