Buckwheat Starch Isolated From Varieties Grown in Washington State: A Qualitative Characterization

Area of Science:

• Food Science and Technology
• Agricultural Science
• Biochemistry

Background:

• Buckwheat is a gluten-free pseudocereal with high starch content, offering potential in food products.
• Understanding varietal differences in buckwheat's technofunctional properties is crucial for food applications.

Purpose of the Study:

• To characterize and compare the chemical, functional, thermal, pasting, and morphological attributes of starch isolated from two buckwheat varieties (Koto and Tinker).
• To investigate the relationship between buckwheat starch properties and its suitability for food product development.

Main Methods:

• Isolation of starch from Koto (KB) and Tinker (TB) buckwheat varieties.
• Analysis of starch purity, amylose content, ash, protein, morphology (microscopy), solubility, swelling power, thermal properties (DSC), and pasting characteristics (viscosity).
• Pearson correlation analysis to determine relationships between starch attributes and functional properties.

Main Results:

• High starch purity (85.21%-89.31%) and amylose content (23.06%-25.04%) were observed, with significant varietal differences.
• Buckwheat starch granules were polygonal/spherical, smooth-surfaced, and ranged from 1.84-14.60 µm.
• Solubility and swelling power increased with temperature; thermal profiles were similar (70.31-71.11°C).
• Koto buckwheat starch exhibited higher peak viscosity, correlated positively with starch content and amylose, but inversely with water solubility and swelling.

Conclusions:

• Buckwheat starches, particularly from Koto and Tinker varieties, demonstrate favorable functional and pasting attributes.
• These properties indicate significant potential for buckwheat starch utilization in various food products, including bakery items, ready-to-eat meals, and frozen foods.