Work

Microwave-induced complexation between sorghum starch and caffeic acid: Structural modulation and its impact on digestive and retrogradation properties

Year: 2025

Type: article

Abstract: Microwave-assisted technology offers an efficient and eco-friendly method for starch modification. In this study, sorghum starch (SS) was treated under varying microwave durations and complexed with caffeic acid (CA) to form SS-CA complexes. Microwave treatment significantly reduced crystallinity (24.07 % to 3.51 %), disrupted short-range order, and caused granule swelling, aggregation, and decreased thermal stability. Complexation induced a V -type inclusion structure. The SS-CA (120 s) complex showed a 9.17 % reduction in rapidly digestible starch (RDS) and a 14.40 % increase in resistant starch (RS). Molecular docking and DFT analyses confirmed that hydrogen bonding and van der Waals forces dominated SS–CA interactions. During 0–7 days of storage, free water content in the SS-CA gel increased only 1.58 % compared to 5.93 % in native SS, indicating reduced retrogradation. The SS-CA complex displayed lower gelatinization enthalpy and improved phase stability. These findings suggest the potential of microwave-assisted SS-CA complexes in developing low-glycemic starch-based foods. • Microwave treatment effectively disrupted sorghum starch (SS) crystallinity and short-range ordering. • Microwave-assisted complexation promoted V-type inclusion between SS and caffeic acid (CA). • SS-CA complexes exhibited enhanced resistant starch content and antioxidant activity. • Retrogradation and water migration in SS-CA gels were significantly reduced during storage.

Source: Food Chemistry X

DOI: 10.1016/j.fochx.2025.103274