Characterization of Botanical Starches and Plant Extracts as Raw Materials for Antioxidant-Based Edible Film Production
T.A., Odeyemi
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
C.I., Owuamanam
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
J.N., Ugwoezuonu
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
L.N., Iroagba
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
F.P., Okezie
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
O.O., Ebia
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
A.C., Igbozuruike
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
A.F., Ofoedum
*
Department of Food Science and Technology, School of Engineering and Engineering Technology, Federal University of Technology, Owerri, Imo State, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
This study comprehensively characterized starches from locally abundant botanical sources—plantain (Musa paradisiaca) and yam (Dioscorea rotundata), using commercial corn starch (Zea mays) as a control—to evaluate their suitability as biopolymer matrices for edible films. Concurrently, the antioxidant potential of extracts from avocado (Persea americana), ginger (Zingiber officinale), and garlic (Allium sativum) was assessed to identify effective natural additives for developing active packaging systems. Starches were isolated using a standardized aqueous sedimentation method, whereas bioactive extracts were obtained through solvent-assisted maceration and hexane extraction. The materials were subjected to physicochemical characterization (pH, moisture content, swelling power, and solubility), structural analysis using Fourier transform infrared spectroscopy (FTIR), morphological examination using scanning electron microscopy (SEM), and antioxidant assays (DPPH, ABTS, and FRAP). The results revealed statistically significant (p < 0.05) differences in the functional properties of the starches. Notably, plantain starch exhibited the lowest swelling power (1.05 mL/g) and moderately favourable solubility (10.87%), indicating a high degree of granular rigidity and potential for forming a water-resistant, cohesive film. This functional balance was supported by structural analysis; SEM micrographs showed that plantain starch granules were oval, smooth, and structurally intact, in contrast to the irregular, porous granules of yam and the smaller, polygonal granules of corn. FTIR analysis further indicated a well-ordered molecular structure in plantain starch, supporting its potential to form a cohesive and stable film matrix. Antioxidant assays indicated that all three plant extracts possessed antioxidant activity, with ginger extract showing the strongest responses in the DPPH and FRAP assays. Overall, plantain starch appeared to be a promising biopolymer candidate for edible-film production because of its balanced physicochemical properties and granular morphology. Incorporating an antioxidant extract, such as ginger extract, into a plantain-starch matrix may provide a basis for developing active, biodegradable packaging materials. This preliminary phase of raw-material characterisation provides a foundation for the valorisation of local agricultural resources and the future development of alternatives to synthetic plastics.
Keywords: Starch characterization, plant extracts, antioxidant activity, plantain starch, edible film, biodegradable packaging