Persimmon preservation using edible coating of chitosan enriched with ginger oil and visualization of internal structure changes using X-ray computed tomography.

The incorporation of ginger oil (GO) influenced the physical, optical, and structural properties of the chitosan (CH) film including the decreases of moisture content (60.15 %), water solubility (35.37 %) and water vapor permeability (WVP) (32.79 %) and the increases of tensile strength (TS) (125 %), elongation at break (EAB) (2.74 %) and opacity (131.08 %). Antifungal capacity of the CH film was enhanced when GO was added to the film. The CH + GO film showed a less homogeneous surface that the presence of the oil droplets on the film surface. Moreover, the CH and CH + GO coatings reduced weight loss of persimmon by 14.87 %, and 21.13 %, respectively, compared to the control. Moisture content loss of the coated CH- and the coated CH + GO- persimmons was decreased by 1.94 % and 4.92 %, respectively, compared to that of the control persimmon. Furthermore, the CH and CH + GO coatings decreased in color changes, respiration rate, ethylene production, changes in pH and TSS, and remained firmness of persimmon during storage at 25 °C. In addition, X-ray CT images can be used to monitor internal changes and observe the tissue breakdown during storage period. The ΔGS value can be used as a predictor of persimmon internal qualities. Thus, the CH film containing GO can be applied as an active packaging material.

Improvement of cross-linked films based on chitosan/diepoxy-poly (ethylene glycol) incorporating trans-cinnamaldehyde essential oil: Preparation, properties, and application in banana storage.

In this study, development of bioactive coatings containing 1 % (w/v) chitosan (CS), 0.6 % (w/v) diepoxy-polyethylene glycol (PEG), and trans-cinnamaldehyde (CIN) was achieved. The physicochemical and biological properties of the coatings were investigated. The tensile strength, light transmission, water vapor permeability (WVP), and antibacterial properties were enhanced by the incorporation of CIN. The CIN-containing films appeared compact and rough, as observed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). In addition, the quality attributes of the bananas were evaluated at room temperature for 24 days, and the results showed that the CS/PEG/CIN coating delayed the respiration peak, weight loss, sugar content loss, and maintained firmness, color, total soluble solids (TSS), titratable acid (TA), and the appearance of the bananas. Principal component analysis (PCA) revealed that the bioactive coating significantly affected the respiration rate and weight loss of bananas.