Role of short germination and milling on physical properties, amino acid and metabolomic profiles of high amylose rice fractions

Food Res Int. 2023 Dec;174(Pt 1):113556. doi: 10.1016/j.foodres.2023.113556. Epub 2023 Oct 4.

Abstract

Short germination is a process that can improve bioactive compounds in rice. This work aimed investigate the physical properties, phenolic compounds (PC), antioxidant activity and amino acids composition of husk + bran, brown and milled rice with high amylose content after short germination (16 h). α-amylase activity (Falling Number, FN) and enthalpy (ΔH) were unchanged (p < 0.05). RVA curve profiles were similar, even though after short germination and milling. Globally, metabolomics analysis identified 117 PC, in which 111 (bound), 104 (free) and 21 revealed in both extracts. p-Coumaric, trans-ferulic and ferulic acids were the most abundant PC revealed in all fractions. The portion husk + bran showed the highest level of total antioxidant activity (709.90 µmol TE) in both free and bound fractions. In terms of total amino acids, there was no statistical difference (p < 0.05) among non-germinated and germinated samples, contrary to free amino acids content. Glutamic acid (Glu) presented the highest values combining short germination and milling (1725-1900 mg/100 g) consequently, leads to higher value of GABA (12.21 mg/100 g). The combination of short germination and milling demonstrated a good strategy to improve the nutritional quality of rice, unless the thermal and pasting properties have been altered, contribute to potential health benefits on human nutrition.

Keywords: HPLC; LC-MS-MS; Milling; Phenolic compounds; Short germination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids* / analysis
  • Amylose / analysis
  • Antioxidants / analysis
  • Glutamic Acid / analysis
  • Humans
  • Oryza* / chemistry
  • Phenols / analysis
  • Seeds / chemistry

Substances

  • Amino Acids
  • Antioxidants
  • Amylose
  • Phenols
  • Glutamic Acid