Physicochemical and Digestion Properties of Potato Starch Were Modified by Complexing with Grape Seed Proanthocyanidins

Abstract

Dietary intake of potato starch could induce a dramatic increase in blood glucose and is positively associated with chronic metabolic diseases (type II diabetes, cardiovascular disease, etc.). Grape seed proanthocyanidins (GSP) are known to decrease starch digestion by inhibiting digestive enzymes or changing the physicochemical properties of starch. In the present study, GSP were complexed with potato starch to prepare polyphenol-starch complexes. The physiochemical properties and digestibility of complexes were investigated by in vitro digestion model, X-ray diffraction, differential scanning calorimetry, rapid visco analyzer, Fourier transform infrared spectroscopy as well as texture profile analysis. Results indicated that the peak viscosity, breakdown, trough, and setback of the complexes disappeared, replaced by a special continuous increase in paste viscosity. The complexes showed a lower final viscosity and higher thermal stability with the increasing binding amount of GSP. GSP decreased the hardness of the complexes' gel significantly. FT-IR indicated that GSP might interact with potato starch through noncovalent forces. Additionally, the complexes also showed a higher content of slowly digestible starch and resistant starch than that of the native starch. Thus, we inferred that the addition of GSP could modify the digestibility of potato starch and be an optional way to modify the starch with lower digestion.

Keywords: complex; in vitro digestion; physicochemical properties; potato starch; proanthocyanidins.

Figure 1

X-ray diffraction analysis of the native starch, GSP–potato starch complexes and GSP. (A) Native starch; (B) Starch + 0.0% GSP; (C) Starch + 1.0% GSP; (D) Starch + 2.0% GSP; (E) Starch + 3.0% GSP; (F) Starch + 4.0% GSP; (G) Starch + 4.5% GSP; (H) Starch + 5.0% GSP; (I) GSP.

Figure 2

Pasting properties of native starch and GSP–potato starch complexes with different binding amounts of GSP.

Figure 3

Fourier transform infrared analysis of the native starch and GSP-potato starch complexes. (A) Native starch; (B) Starch + 0.0% GSP; (C) Starch + 1.0% GSP; (D) Starch + 2.0% GSP; (E) Starch + 3.0% GSP; (F) Starch + 4.0% GSP; (G) Starch + 4.5% GSP; (H) Starch + 5.0% GSP.

Figure 4

Effect of GSP–potato starch interactions on digestible properties of native starch and GSP-potato starch complexes. RDS, SDS, and RS represent rapidly digestible starch, slowly digestible starch, and resistant starch, respectively. Error bars indicate ± standard deviation. The same letters within starch digestibility types are not significantly different (p < 0.05).