Variations of Free Amino Acids during the Germination of Brown Foxtail Millet

Abstract

Germination can improve the level of the free amino acid, and further improve the nutritious value of the foxtail millet. However, the effect of germination temperature and time on them is still unclear. The free amino acid of the germinated foxtail millet has been analyzed at different germination temperatures (20, 25, 30, 35, and 40 ℃) and time (0, 6, 12, 18, 24, and 30 h). Results reveal that 21 components of free amino acids increased. The lower temperature or higher temperature is not suitable for the accumulation of the free amino acid. The free amino acids increase to the maximum at the germination temperature of 30 ℃ for 30 h. The total free amino acids and total essential free amino acids can reach (810.7±69.0) and (367.8± 30.2) mg/100g, respectively. Among the amino acids, the contents of alanine and threonine increase to the highest level. The alanine has increased to (120.0±12.0) and (115.0±14.0) mg/100g at the temperature of 30 and 35 ℃, respectively. The threonine has increased to (106.0±1.0) mg/100g at the temperature of 35 ℃. The γ-aminobutyric acid reaches the maximum level at the germination temperature of 35 ℃ and reaches (60.1±1.8) mg/100g. In conclusion, the germination can promote the increase of the free amino acid and adjust the nutrition of the foxtail millet, and the germinated foxtail millet is a potential source for functional food.

Keywords

• brown foxtail millet
• germination temperature
• germination time
• free amino acid
• γ-aminobutyric acid