Insight into formation and structure of wheat starch-lauric acid complexes by extrusion: Effect of plasma-activated water

The objective of this study is to examine how plasma-activated water (PAW) affects the formation of complexes between wheat starch (WS) and lauric acid (LA) during extrusion. The findings from various analysis, including complexing index, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, and differential scanning calorimetry, revealed that PAW promoted the formation of WS-LA complexes during extrusion, resulting in a better long-range and short-range ordered structure, as well as higher gelatinization enthalpy. Consequently, PAW led to lower solubility, swelling power, gel property, and rapidly digestible starch content but higher resistant starch content. Notably, the promotional impact of PAW60 (distilled water underwent plasma treatment for 60 s) was greater than PAW120 (distilled water underwent plasma treatment for 120 s) and PAW180 (distilled water underwent plasma treatment for 180 s). This study provides an efficacious technique to enhance the formation of starch complexes, being of great value in starch-based functional foods.