Application potential and technological properties of colored sweet potato starches

Abstract

The objective of this study is to demonstrate the application potential of starches extracted from four varieties of colored sweet potatoes by determining their technological, thermal, and pasting properties. The purple sweet potato (PSP) starch presents the largest mean diameter (14.2 µm). The white sweet potato (WSP), orange sweet potato (OSP), beige sweet potato (BSP), and PSP starches present an inconspicuous triplet on the nuclear magnetic resonance (NMR). The WSP and OSP starches show CA-Type and the BSP and PSP starches show A-Type characteristics on the X-ray spectrum. The BSP and PSP starches show the presence of peaks in amorphous regions on the Fourier transform infrared (FT-IR) spectroscopy. The differential scanning colorimetry (DSC) thermogram of the BSP and PSP starches show lower gelatinization energies and wider gelatinization temperature ranges (difference between the conclusion and onset temperatures). The viscoamylographic profiles of the WSP and OSP starches show greater thermal stability. These technological properties demonstrate the potential application of these starches in sauces, snacks, instant soups, dairy desserts, yogurts, and bread.