Study on hydrophobic modification of basil seed gum-based (BSG) films by octenyl succinate anhydride (OSA)

The main objective of this study was to evaluate the changes in the characteristics of basil (Ocimum bacilicum L.) seed gum (BSG) films after modification with octenyl succinate anhydride (OSA) at different OSA:BSG weight ratios (WRs) of 0, 0.01 and 0.03. HPLC analysis revealed that the amount of added OS groups was 0%, 0.28%, and 1.01%, respectively. The introduction of OS groups along the BSG backbone was also confirmed by FT-IR and NMR analysis. XRD results revealed no significant change of physical state after modification. The contact angle (i.e., hydrophobicity) of modified BSG films was higher than that of control film. A decrease in the film solubility in water (29%) and water vapor permeability (50%), but an increase in density (14.28%) and opacity (21.37%) was observed after modification at the WR of 0.03. Also, the results showed that modification with OSA had no significant influence on the film thickness, moisture content and color properties. BSG modification with OSA at the WR of 0.03 significantly increased the flexibility and ultimate strength of respective films. The results of this study showed that OSA-modified BSG is a good candidate for developing edible films and coating with relatively high resistance to water.