Characterization of flour from Philippine sweet potato (ipomoea batatas) varieties as potential functional food ingredient / Rowena Grace R. Sanchez

Dissertation (Doctor of Philosophy in Food Science) -- University of the Philippines, Diliman, January 2024.

Characterization of 19 Philippine sweetpotato (Ipomoea batatas) cultivars and its flours in terms of proximate and mineral composition and antioxidant properties were performed. In addition, sweetpotato flour (SPF) samples were evaluated for physico-chemical, pasting and gelatinization characteristics. Principal component (PCA) and hierarchical cluster analyses (HCA) were conducted for information reduction, data visualization and sample classification based on similarities. Significant (p <0.05) variations for almost all parameters were observed among cultivars. Effects of flour processing varied depending on the cultivar. Contributions of phenolics and flavonoids to the antioxidant activities were indicated by significant (p<0.01) and strong positive correlations among TPC, TFC, ORAC, among and DPPH assays. Flour produced from the purple- fleshed cultivar (SG-08-0 consistently exhibited the highest TPC (211.72 mg GAE/100 g), TFC (98.56 mg CE/100 g), ORAC (4251.15 μmol Trolox/100 g), and DPPH (10302.74 μmol TE/100 g) levels and the highest dry matter assuring high flour yields, making it ideal as an alternative flour source with health benefits. Wide variations in terms of physico- chemical, pasting and gelatinization properties of SPF samples were observed. PCA and HCA grouped together similar SPF samples which can guide the selection of suitable applications for each cultivar including those high in antioxidants that are ideal in enhancing health beneficial properties of diverse functional foods and beverages and those with high pasting viscosities that are useful in products requiring high gel strength and elasticity such as noodles or bakery products.