Investigation of functional additives in chitosan-based edible coatings and their impact on physicochemical, bioactive, and microbial stability of orange-fleshed sweet potatoes (OFSP) during storage

Krishnan, Rohan Rama; Patel, Keya Himanshu; Olasupo, Abdulhakeem Dapo; Nkwonta, Chikere; Bolarinwa, Islamiyat Folashade; Oke, Moruf Olanrewaju; Xu, Xiafei; Wu, Jingwen; Yong, Andrea; Li, Ping; Liang, Ziqi; Ifie, Idolo

Abstract

The efficacy of chitosan-based edible coatings (EC) in enhancing postharvest quality and extending the shelf life of orange-fleshed sweet potatoes (OFSP) is thoroughly investigated in this study. Six EC treatments (T2-T7) containing either chitosan alone/lemongrass essential oil (LEO), and/or citric/ ascorbic acids were applied to OFSP and stored under controlled atmospheric conditions (20 °C, 75 ± 5 % RH) for 28-day period along with an uncoated sample (T1). The samples were analysed weekly for the changes in physicochemical properties (weight loss, colour and texture), total phenolic content (Folin assay), antioxidant capacity (TEAC), bioactive components (HPLC) and microbial load. The results showed that T5 (chitosan/LEOs) and T7 (chitosan/LEOs/ascorbic/citric acid) coatings were particularly effective. T5 exhibited the least weight loss (5.65 %), while T1 (uncoated samples) recorded the greatest weight loss (13.23 %) by day 28. The main phenolic compounds identified in OFSP samples were 4-Caffeoylquinic Acid (4-CQA) and 3,5-Caffeoylquinic Acid (3,5-diCQA). At the end of the storage period, T5 displayed the highest TPC of 3.33 mg GAE g-1, while T7 recorded the highest β-carotene content (0.72 ± 0.09 mg g⁻¹) and were significantly different from uncoated samples (p < 0.05), suggesting the role of chitosan/ antioxidants in the stability of bioactive compounds. ECs especially T5 and T7 displayed strong antimicrobial properties, which were demonstrated by their significant reduction of mesophilic bacterial counts compared to the control (p < 0.05). This work establishes a basis for developing bioactive coatings for preserving the quality and safety of OFSP, contributing to improved food security and nutritional outcomes.

Citation

Krishnan, R. R., Patel, K. H., Olasupo, A. D., Nkwonta, C., Bolarinwa, I. F., Oke, M. O., Xu, X., Wu, J., Yong, A., Li, P., Liang, Z., & Ifie, I. (2025). Investigation of functional additives in chitosan-based edible coatings and their impact on physicochemical, bioactive, and microbial stability of orange-fleshed sweet potatoes (OFSP) during storage. Scientia Horticulturae, 340, Article 113956. https://doi.org/10.1016/j.scienta.2025.113956

• Journal Article Type: Article
• Acceptance Date: Jan 3, 2025
• Online Publication Date: Jan 10, 2025
• Publication Date: Jan 15, 2025
• Deposit Date: Mar 25, 2025
• Publicly Available Date: Mar 25, 2025
• Journal: Scientia Horticulturae
• Print ISSN: 0304-4238
• Electronic ISSN: 1879-1018
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 340
• Article Number: 113956
• DOI: https://doi.org/10.1016/j.scienta.2025.113956
• Public URL: https://durham-repository.worktribe.com/output/3741117