Structural characterization and Pickering emulsifying ability of Tartary buckwheat starch prepared by natural deep...

Area of Science:

• Food Science
• Materials Science
• Green Chemistry

Background:

• Tartary buckwheat starch (TBS) is a valuable food ingredient.
• Traditional extraction methods may impact starch properties.
• Natural deep eutectic solvents (NADES) offer a sustainable alternative for extraction.

Purpose of the Study:

• To evaluate a betaine-ethylene glycol NADES as a model extraction medium for Tartary buckwheat starch (TBS).
• To compare the physicochemical properties and emulsion-forming behavior of NADES-extracted TBS (NADES-TBS) with alkali-extracted TBS (AE-TBS).

Main Methods:

• Optimized NADES extraction conditions (molar ratio, water content, time).
• Analyzed starch content, amylose content, granule morphology, crystallinity, and pasting properties.
• Assessed interfacial properties (interfacial tension, contact angle) and Pickering emulsion formation.

Main Results:

• Optimal NADES extraction yielded 87.34% starch content, comparable to AE-TBS.
• NADES-TBS showed lower apparent amylose content, slightly larger particle size, and altered pasting properties (higher pasting temperature, lower viscosity).
• NADES-TBS demonstrated reduced oil-water interfacial tension and formed smaller Pickering emulsion droplets under short-term conditions.

Conclusions:

• The betaine-ethylene glycol NADES system is a viable method for TBS extraction, yielding starch with modified properties.
• NADES-TBS exhibits potential for applications in Pickering emulsion stabilization.
• Further investigation is needed regarding residual solvent, molecular structure, and long-term emulsion stability for food applications.