Preliminary investigation on the effect of insect-based chitosan on preservation of coated fresh cherry tomatoes

Abstract

Chitosan was produced from Hermetia illucens pupal exuviae by heterogeneous and homogeneous deacetylation. Tomato fruits (Solanum lycopersicum), that are one of the most grown and consumed food throughout the world, were coated with 0.5 and 1% chitosan, applied by dipping or spraying, and stored at room temperature or 4 °C, for a storage period of 30 days. Statistical analysis give different results depending on the analysed parameters: heterogeneous chitosan, indeed, had a better effect than the homogenous one in maintaining more stable physico-chemical parameters, while the homogenous chitosan improved the total phenols, flavonoids and antioxidant activity. Chitosan coatings applied by spraying were more effective in all the analyses. Chitosan derived from H. illucens always performed similarly to the commercial chitosan. However, a general better performance of insect-derived chitosan on the concentration of phenolics and flavonoids, and the antioxidant activity was observed as compared to the commercial one. Chitosan coating has already been successfully used for preservation of fresh fruits, as alternative to synthetic polymers, but this is the first investigation of chitosan produced from an insect for this application. These preliminary results are encouraging regarding the validation of the insect H. illucens as a source of chitosan.

Update on Chitin and Chitosan from Insects: Sources, Production, Characterization, and Biomedical Applications

“…Chu et al found that both DPPH radical scavenging and ferric-chelating assays showed a positive correlation with the deacetylation degree of chitosan isolated from superworm (Zophobas morio) larvae [39]. Tafi et al reported that chitosan from Hermetia illucens as a coating for the preservation of a fresh food product was generally able to increase the phenolic and flavonoid content and the antioxidant activity of tomatoes during both RT and cold storage [144].…”

Usage of chitosan from Hermetia illucens as a preservative for fresh Prunus species fruits: a preliminary analysis

“…Coating solutions were prepared according to the method by Hassan et al and Tafi et al [8,57]. Chitosan (0.5% w/v or 1% w/v) was dissolved in a solvent solution consisting of 1% v/v acetic acid, 2% v/v glycerol and 0.2% v/v Tween-80.…”

“…Fruits were coated by spraying using an aerograph (Martellato s.r.l., Rovigo, Italy) and then dried at room temperature for 30 min. The spraying with the coating solution was repeated twice to ensure uniform surface coverage, as reported by Tafi et al [57]. One half of the fruit of each treatment was stored at room temperature (RT), while the other half was stored at refrigeration temperature (4 °C).…”

Chitosan and Its Derivatives: Preparation and Antibacterial Properties

“…The inherent antibacterial quality of these films plays a pivotal role in mitigating bacterial growth within food products, consequently extending their shelf life and upholding the standard of food quality. As a consequence, these films are frequently harnessed in the context of food packaging, underlining their significance in bolstering food safety and minimizing waste [ 89 , 90 , 144 , 145 , 146 , 147 , 148 , 149 ].…”