Optimization of Germination Conditions for γ-Aminobutyric Acid Accumulation and Component Analysis of Black Tartary Buckwheat

In order to improve the effective utilization rate of blacktartary buckwheat and realize its high value-added utilization, the germination parameters were optimized using one-factor-at-a-time method and response surface methodology. Furthermore, the changes in the contents of basic nutritional components and bioactive compounds in black tartary buckwheat were investigated before and after germination. The optimal germination conditions were determined as follows: Germination time of 4 days, germination temperature of 25 ℃, soaking temperature of 25 ℃, soaking time of 6 h. Under these conditions, the content of GABA in blacktartary buckwheat was 33.40 mg/100 g. The results showed that the concentrations of carbohydrate, total phenol, total flavonoids, quercetin, kaempferol, epicatechin, and chlorogenic acid were significantly increased compared with that before germination. Specially, chlorogenic acid and epicatechin concentrations were 16.14 and 11.05 times that of those before germination, respectively. Moreover, kaempferol and quercetin contents increased by 86.4% and 83.5%, respectively. Total phenols and flavonoids concentrations increased by 57.1% and 28.6%, respectively. The contents of crude protein and crude fat were similar before and after germination, while the contents of ash and rutin decreased significantly（P<0.05）. The results of this study would provide new ideas and a theoretical basis for further processing and development of black tartary buckwheat.