Effect of microwave treatment and water-bath heating treatment on the performance of glutenin from Tiger nut seed meal: Insights into changes in structural characteristics, functional properties, and in vitro gastrointestinal digestibility

Abstract

In this study, the structural characteristics, functional properties, and in vitro gastrointestinal digestibility of glutenin from Tiger nut seed meal (TNSMG) treated by microwave (140–700 W, 20–60 s) and water-bath heating (40–100 °C, 10–30 min) were investigated. Analysis of the surface hydrophobicity, intrinsic fluorescence spectroscopy and Fourier transform infrared spectroscopy indicated that both microwave and water-bath heating treatments caused structure changes of TNSMG. The results showed an increase in the exposure of sulfhydryl groups and the content of β-sheet, coupled with a decrease in the content of α-helix and β-turn. These structural changes contributed to the improved solubility, foamability, emulsification properties, and digestibility of TNSMG under proper thermal treatment conditions. TNSMG exhibited the best solubility (68.48%) and foamability (85.56%) after water-bath heating treatment for 20 min at 80 °C. Furthermore, TNSMG showed the best emulsification property (9.61 m2/g) and digestibility (78.58%) when treated by microwave treatment at 560 W for 40 s.

Keywords

• Tiger nut seed meal glutenin
• Microwave treatment
• Water-bath heating treatment
• Structure
• Functional properties
• Digestibility