Impact of germination on nutritional and physicochemical properties of adlay seed (Coixlachryma-jobi L.)

- Coixol and GABA contents of adlay flour significantly increased after germination.
- Germination led to the protein hydrolysis and starch degradation.
- Germination led to changes in pasting and thermal characteristics of adlay flour.
- Changes in micrographs and FTIR peaks were observed during germination process.

Adlay has garnered a great deal of research attentions in recent years as a highly nutritious food material and herbal medicine. This study characterized the changes of nutritional and physicochemical properties of adlay seeds during a 60-h germination. The results showed that the 60-h germination brought about a 3.4-fold increase in γ-aminobutyric acid (GABA) and 3.6-fold increase in coixol compared to ungerminated adlay seeds, while the triolein content slightly decreased. Some high molecular proteins were hydrolyzed into smaller proteins, peptides and amino acids after germination. Scanning electron micrographs (SEM) showed that the germination process destroyed the continuous matrix structure of adlay flour and created pits and holes on the surface of some starch granules. Germination resulted to changes in the pasting and gelatinization properties of adlay flour. The results of present study suggest that germination efficiently enhances the nutritional compounds while altering the physicochemical characteristics of adlay seeds.