Browsing by Author "Feben Girma"

Now showing 1 - 1 of 1
  • No Thumbnail Available
    Item
    Characterization of Active Edible Packaging Film Based on Orange Fleshed Sweet Potato Starch and Moringa Stenopetala Leaf Extract
    (Addis Ababa University, 2024-09) Feben Girma; Shimelis Kebede (PhD)
    In order to maintain food quality and increase shelf life, food packaging is essential, and the rising demand for sustainable materials has spurred research into biopolymer-based active films. This study investigates the development and characterization of orange fleshed sweet potato starch based films incorporating Moringa stenopetala leaf extract. Commercial corn starch served as the control, while the orange fleshed sweet potato starch was extracted and modified through pre-gelatinization; a physical process of heating starch with water to break its structure, making it more easily dissolvable and absorbent, resulting in significantly higher (P < 0.05) swelling power, solubility, water binding capacity, and pasting clarity. X-ray diffraction patterns of native and pre-gelatinized orange fleshed sweet potato starches were similar (C-type) and chemical structures but the modified starch demonstrated superior thermal properties. A microwave-assisted extraction technique was used to maximize the Moringa stenopetala leaf extract, which was then added to the film, with response surface methodology used to optimize concentrations of modified starch, glycerol, and leaf extract to 4g, 40% w/w, and 1.5% w/w, respectively, for active bio-plastic film production. The tensile strength of the optimized film increased significantly from 7.06 MPa to 7.38 MPa, and its water vapor permeability improved to 3.145×10⁻⁹ g m⁻¹s⁻¹Pa⁻¹ compared to the pure film’s 3.225×10⁻⁹ g m⁻¹s⁻¹Pa⁻¹. It is important to remember that these comparisons are conducted at the same film thickness because differences in thickness can have an impact on both TS and WVP, which could compromise the comparison's accuracy. Moringa extract showed level of phenolic compounds of 8.56±0.04 mg GAE/g, a total flavonoid content of 9.38±0.26 mg QE/g, and a ferric reducing capacity of 8.72±0.08 mg AAE/g, while the active film contained 6.08±0.06 mg GAE/g phenolics, 6.30±0.21 mg QE/g flavonoids, and 3.18±0.04 mg AAE/g ferric reducing capacity. Antimicrobial testing revealed zone of inhibition values of 12.0±0.02 mm for MSLE and 9.2±0.42 mm for the active film against Staphylococcus aureus, and 9.0±0.48 mm for MSLE and 6.0±0.43 mm for the active film against Escherichia coli. The active films developed showed good antioxidant capacity, improved antibacterial activity, and biodegradability within 30 days. The study concludes that orange fleshed sweet potato starch films with moringa extract have promising potential for biodegradable packaging, offering reduced environmental impact and improved food safety.