## 3 Results and Discussions
### Taste Characteristics
\begin{table}
\begin{tabular}{l c c c c c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**Threshold**} & \multicolumn{3}{c}{**Concentration (mg/100 g)**} & \multicolumn{3}{c}{**TAV**} \\ \cline{3-13}
**FAA** & **(mg/100 g)** & **Taste** & \multicolumn{3}{c}{**SF**} & **L.P.** & **P.A.** & **P.P.** & **SF** & **L.P.** & **P.A.** & **P.P.** \\ \hline Asp & 3 & umami & 5.51 \(\pm\) 0.32 \({}^{\rm d}\) & 45.6 \(\pm\) 1.7 \({}^{\rm b}\) & 42.1 \(\pm\) 1.1 \({}^{\rm c}\) & 52.1 \(\pm\) 1.9 \({}^{\rm a}\) & 1.84 & 15.19 & 14.05 & 17.36 \\ Glu & 5 & umami & 49.0 \(\pm\) 3.3 \({}^{\rm d}\) & 56.8 \(\pm\) 2.7 \({}^{\rm b}\) & 51.8 \(\pm\) 1.6 \({}^{\rm c}\) & 67.8 \(\pm\) 2.47 \({}^{\rm a}\) & 9.80 & 14.05 & 17.26 & 22.61 \\ Ser & 150 & sweet & 4.61 \(\pm\) 0.26 \({}^{\rm a}\) & 2.97 \(\pm\) 0.31 \({}^{\rm c}\) & 2.24 \(\pm\) 0.06 \({}^{\rm d}\) & 3.66 \(\pm\) 0.13 \({}^{\rm b}\) & 0.03 & 0.02 & 0.01 & 0.02 \\ Gly & 150 & sweet & 23.2 \(\pm\) 1.3 \({}^{\rm a}\) & 19.4 \(\pm\) 0.8 \({}^{\rm c}\) & 21.1 \(\pm\) 0.5 \({}^{\rm b}\) & 21.6 \(\pm\) 0.7 \({}^{\rm b}\) & 0.15 & 0.13 & 0.14 & 0.14 \\ Thr & 260 & sweet & 9.26 \(\pm\) 0.53 \({}^{\rm c}\) & 14.2 \(\pm\) 0.4 \({}^{\rm b}\) & 17.8 \(\pm\) 0.4 \({}^{\rm a}\) & 18.4 \(\pm\) 0.7 \({}^{\rm a}\) & 0.04 & 0.05 & 0.07 & 0.07 \\ Ala & 60 & sweet & 58.5 \(\pm\) 3.3 \({}^{\rm a}\) & 44.3 \(\pm\) 1.4 \({}^{\rm c}\) & 45.2 \(\pm\) 1.2 \({}^{\rm c}\) & 47.5 \(\pm\) 1.7 \({}^{\rm b}\) & 0.97 & 0.74 & 0.75 & 0.79 \\ Pro & 300 & sweet/bitter & 51.9 \(\pm\) 2.9 \({}^{\rm b}\) & 51.8 \(\pm\) 3.5 \({}^{\rm b}\) & 46.5 \(\pm\) 1.2 \({}^{\rm c}\) & 56.6 \(\pm\) 2.1 \({}^{\rm a}\) & 0.17 & 0.17 & 0.15 & 0.19 \\ Lys & 50 & sweet/bitter & 12.6 \(\pm\) 0.7 \({}^{\rm c}\) & 45.1 \(\pm\) 1.2 \({}^{\rm a}\) & 44.2 \(\pm\) 1.1 \({}^{\rm b}\) & 46.4 \(\pm\) 1.6 \({}^{\rm a}\) & 0.25 & 0.90 & 0.88 & 0.93 \\ Arg & 50 & bitter & 1.97 \(\pm\) 0.11 \({}^{\rm b}\) & 25.3 \(\pm\) 0.36 \({}^{\rm a}\) & 1.11 \(\pm\) 0.03 \({}^{\rm d}\) & 1.48 \(\pm\) 0.05 \({}^{\rm c}\) & 0.04 & 0.05 & 0.02 & 0.03 \\ Val & 40 & bitter & 30.3 \(\pm\) 1.7 \({}^{\rm a}\) & 25.5 \(\pm\) 0.7 \({}^{\rm c}\) & 26.2 \(\pm\) 0.7 \({}^{\rm b}\) & 27.0 \(\pm\) 0.9 \({}^{\rm b}\) & 0.76 & 0.64 & 0.65 & 0.68 \\ Tyr & N.A. & bitter & 20.8 \(\pm\) 1.2 \({}^{\rm c}\) & 27.7 \(\pm\) 0.7 \({}^{\rm a}\) & 24.6 \(\pm\) 0.6 \({}^{\rm b}\) & 25.9 \(\pm\) 0.9 \({}^{\rm b}\) & 0.8 & 0.9 \({}^{\rm b}\) & 0.82 & 0.9 & 0.9 \\ His & 20 & bitter & 30.4 \(\pm\) 1.7 \({}^{\rm c}\) & 76.4 \(\pm\) 3.6 \({}^{\rm a}\) & 79.8 \(\pm\) 2.1 \({}^{\rm a}\) & 70.8 \(\pm\) 2.5 \({}^{\rm b}\) & 1.52 & 3.82 & 3.99 & 3.54 \\ Leu & 190 & bitter & 50.5 \(\pm\) 2.9 \({}^{\rm b}\) & 53.4 \(\pm\) 1.6 \({}^{\rm c}\) & 50.9 \(\pm\) 1.3 \({}^{\rm b}\) & 53.5 \(\pm\) 1.9 \({}^{\rm a}\) & 0.27 & 0.28 & 0.27 & 0.28 \\ Ile & 90 & bitter & 23.2 \(\pm\) 1.3 \({}^{\rm a}\) & 18.1 \(\pm\) 0.7 \({}^{\rm b}\) & 17.5 \(\pm\) 0.5 \({}^{\rm b}\) & 18.4 \(\pm\) 0.7 \({}^{\rm b}\) & 0.26 & 0.20 & 0.19 & 0.20 \\ Phe & 90 & bitter & 38.2 \(\pm\) 2.1 \({}^{\rm a}\) & 41.1 \(\pm\) 1.0 \({}^{\rm a}\) & 37.7 \(\pm\) 0.9 \({}^{\rm b}\) & 39.0 \(\pm\) 1.4 \({}^{\rm b}\) & 0.42 & 0.46 & 0.42 & 0.43 \\ Met & 30 & bitter & 17.8 \(\pm\) 1.0 \({}^{\rm a}\) & 15.2 \(\pm\) 0.6 \({}^{\rm b}\) & 14.3 \(\pm\) 0.3 \({}^{\rm c}\) & 14.9 \(\pm\) 0.5 \({}^{\rm b}\) & 0.59 & 0.51 & 0.48 & 0.50 \\ Cys & N.A. & salt & N.D. & N.D. & N.D. & N.D. & N.D. & N.D. & \\ \hline \hline \end{tabular} Notes: N.A., not available; N.D., not detected. Different letters denote significant differences in the same row (\(p<0.05\)). Thresholds for amino acids adapted from [PERSON] et al. [38].  
\end{table} 
Table 2: Contents (mg/100 g) and taste activity value (TAV) of free amino acids in Zhayu samples prepared by spontaneous fermentation (SF) and fermented with 109 cfu/100 g of _L. plantarum_ (L.P.), _P. acidilactici_ (P.A. ), and _P. pentosaccus_ (P.P.).