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Spoilage of cassava root begins immediately after harvest, but its shelf-life could be enhanced by adopting freezing as a storage method. This study investigated the physicochemical properties and morphology of starch isolated from cassava roots frozen for 0, 7, 14, 21 and 28 days. Extracted starches can be categorized as compound starches with most granules irregularly shaped, with some oval, round and truncated. The amylose contents (22.05-26.41%) decreased with an increase in the freezing time, but the starches showed similar crystallinity pattern (Type A). Fourier infrared transform spectroscopy showed a reduction in double-helical order structure of starches from frozen cassava roots. Starches from the stored roots were generally less firm, less sticky, more cohesive and had higher peak and trough viscosities compared to starch from freshly harvested roots. Starch from frozen cassava starch may be suited for use in certain types of noodles, such as Japanese noodles due to low amylose content. Future studies are however, required to explore the starches in food applications.

The encapsulation of bioactive-rich plant extracts is an effective method of preventing their damage or loss of activity during processing and storage. Here, the techno-functional properties of microcapsules developed from Moringa oleifera leaf powder (MoLP) extract (core) with maltodextrin (MD), gum Arabic (GA), and a combination (MDGA) (coatings) were assessed. The bulk and tap density were 0.177, 0.325 and 0.297 g/mL and 0.13, 0.295 and 0.259 g/mL for GA, MD and MDGA microcapsules, respectively. Flowability properties of microcapsules indicated an intermediate flow except for GA which had a poor flow. The moisture content of the microcapsules ranged from 1.47% to 1.77% with no significant differences (p > 0.05) observed. All the microcapsules had high water solubility (86.35% for GA to 98.74% for MD and 90.51% for MDGA). Thermogravimetric analyses revealed that encapsulation enhanced the thermal stability of the core material. The X-ray diffraction analysis revealed that the microcapsules and extracts have an amorphous nature, which was validated by the surface morphology analysis that showed amorphous, irregular, and flake-like attributes except for MDGA microcapsules which had slightly spherical and agglomerated surfaces. The Fourier Transform Infra-Red spectra of the microcapsules showed the presence of C-O and O-H aromatic rings as well as amine groups. New spectra were observed at 1177, 1382 and 1411 cm−1 for MDGA, MD and GA, respectively, after encapsulation, which connotes a slight modification in the chemical structural pattern after encapsulation. Storage stability tests (28 days at 4, 25 and 40 °C) showed that the microcapsules were most stable at 4 °C and the stability differs significantly (p ≤ 0.05) with coating material type and temperature with MDGA showing better storage stability than others. Altogether, the attributes of the MDGA microcapsules were comparatively better than either MD or GA alone. The present data, therefore, demonstrate an effective encapsulation process for MoLP extract that can serve as fortificants in processed food products where MoLP may be used.