Use of Orange Oil Loaded Pectin Films as Antibacterial Material for Food Packaging

This study aims to develop orange oil loaded in thin mango peel pectin films and evaluate their antibacterial activity against Staphylococcus aureus. The mango peel pectin was obtained from the extraction of ripe Nam Dokmai mango peel by the microwave-assisted method. The thin films were formulated using commercial low methoxy pectin (P) and mango pectin (M) at a ratio of 1:2 with and without glycerol as a plasticizer. Orange oil was loaded into the films at 3% w/w. The orange oil film containing P and M at ratio of 1:2 with 40% w/w of glycerol (P1M2GO) showed the highest percent elongation (12.93 ± 0.89%) and the lowest Young’s modulus values (35.24 ± 3.43 MPa). For limonene loading content, it was found that the amount of limonene after the film drying step was directly related to the final physical structure of the film. Among the various tested films, P1M2GO film had the lowest limonene loading content (59.25 ± 2.09%), which may be because of the presence of numerous micropores in the P1M2GO film’s matrix. The inhibitory effect against the growth of S. aureus was compared in normalized value of clear zone diameter using the normalization value of limonene content in each film. The P1M2GO film showed the highest inhibitory effect against S. aureus with the normalized clear zone of 11.75 mm but no statistically significant difference. This study indicated that the orange oil loaded in mango peel pectin film can be a valuable candidate as antibacterial material for food packaging.