Abstract
White sweet potato has high potential for flour production whose using in food preparations depends on its functional characteristics which in turn depend on variety, pretreatment methods and processing steps. This study investigated the effect of unpeeling and blanching on the chemical composition and functional properties of flour produced from white fleshed sweet potato Algerian cultivar. Sweet potato tubers were divided into two batches: a manually peeled batch and the unpeeled one, which were trimmed and soaked in water during 15 min. Each batch was then divided into two equal parts: one part was blanched in water at 100 °C for 5 min, the second part remained non-blanched. All samples were dried at 60 °C during 24 hours. The flours were analyzed for proximate composition, polyphenol and tannin content, and functional properties. Flour processed from unpeeling sweet potato exhibited higher (p < 0.001) lipid, starch, fiber, polyphenol and tannin content. Blanching decreased significantly polyphenols about 39% and 30% and tannins about 48% and 63%, respectively in unpeeled and peeled blanched SP-based flours. Finally, combination of both unpeeling and blanching increased water absorption capacity, swelling power, water solubility, emulsifying capacity of sweet potato flour which are interesting as properties in various food products.
Keywords:
sweet potato algerian cultivar; blanching; unpeeling; flour; chemical composition; functional properties
Thumbnail
