Article Sidebar
Published:
Oct 10, 2014DOI:
10.4314/tjpr.v13i9.3Keywords:
Article Details
Submission of a manuscript to this journal is a representation that the manuscript has not been published previously and is not under consideration for publication elsewhere.
All authors named in each manuscript would be required to sign a form (to be supplied by the Editor) so that they may retain their copyright in the article but to assign to us (the Publishers) and its licensees in perpetuity, in all forms, formats and media (whether known or created in the future) to (i) publish, reproduce, distribute, display and store the contribution, (ii) translate the contribution into other languages, create adaptations, reprints, include within collections and create summaries, extracts and/or abstracts of the contribution, (iii) create any other derivative works(s) based on the contribution, (iv) to exploit all subsidiary rights in the contribution, (v) the inclusion of electronic links from the contribution to third party material where-ever it may be located, and (vi) license any thrid party to do any or all of the above.
Main Article Content
Characterization of Digestion Resistance Sweet Potato Starch Phosphodiester
Abstract
Purpose: To analyze the physicochemical properties and in vitro digestibility of sweet potato starchphosphodiester prepared using sodium trimetaphosphate.
Methods: The physicochemical properties of sweet potato starch phosphodiester were analyzed by using infrared spectrometry (IR), differential scanning calorimetry (DSC) and rapid visco-analyser (RVA). In addition, an in vitro digestibility method was applied to investigate starch digestion performances.
Results: FTIR spectrum showed new absorption peaks at 1033 cm-1 indicating that an esterification cross-linking reaction was found between sweet potato starch and sodium trimetaphosphate. Similar gelatinization temperature (70 oC), enthalpy change (10 J/g), and peak viscosity (600 cp) were obtained for sweet potato starch phosphodiester and the raw starch indicating that their gelatinization properties were identical. Compared with sweet potato starch, digestible starch content of sweet potato starch phosphodiester decreased sharply (from 63.4 to 15.8 %), while digestion resistance starch content increased significantly (from 14.5 to 58.7 %). Based on completion of starch hydrolysis, the glycaemic index (GI) of sweet potato starch phosphodiester was predicted to be 66.31.
Conclusion: Derived sweet potato starch phosphodiester presents higher digestibility and may be useful as a medium glycemic index (GI) food for diabetic patients.
Keywords: Sweet potato starch, Phosphodiester, Digestion resistance, Digestibility, Glycemic index
