Multi-scale structural evolution during simulated gelatinization process of sweet potato starch by heat-moisture treatment

Sijie Zhang; Weiguo Wu; Jihe Zhu; Junling Wu; Zengpeng Gan; Houqin Deng; Yu Zhang; Luyan Liao

doi:10.1016/j.fochx.2024.102123

Multi-scale structural evolution during simulated gelatinization process of sweet potato starch by heat-moisture treatment

Food Chem X. 2024 Dec 24:25:102123. doi: 10.1016/j.fochx.2024.102123. eCollection 2025 Jan.

Authors

Sijie Zhang¹, Weiguo Wu¹, Jihe Zhu², Junling Wu¹, Zengpeng Gan¹, Houqin Deng^{1

3}, Yu Zhang^{1

3}, Luyan Liao^{1

3}

Affiliations

¹ College of Food Science and Technology, Hunan Agricultural University, Changsha 410128, China.
² School of Food and Pharmacy, Shanghai Zhongqiao Vocational and Technical University, Shanghai 201514, China.
³ Hunan Province Key Laboratory of Food Science and Biotechnology, Changsha 410128, China.

Abstract

The changes in properties and structures of raw sweet potato starch (RAW-SPS) and heat-moisture treatment (HMT) sweet potato starch (HMT-SPS) during gelatinization process (S1-S6) was investigated to elucidate the improvement effect of HMT on SPS. It was found that SPS exhibited the characteristics of pseudoplastic fluids, characterized by shear thinning and thixotropy, belonged to the C-type starch crystal. The gelatinization temperature of SPS was increased to 82.55 °C by HMT. HMT-SPS had better viscoelasticity in S3-S6. The particle size was smaller than that of RAW-SPS during the gelatinization process. The starch paste of S2 was gelatinized by heating at 95 °C, and the original crystalline structure of the starch was destroyed, where layered structure formed by recrystallization was observed. HMT-SPS showed a clear polarization cross, while disappeared after S2. HMT also improved the ordering degree. The results explained the mechanism of changes in HMT modified starch during the gelatinization process.

Keywords: Gelatinization stage; Heat-moisture treatment; Structure changes; Sweet potato starch.