## 2 Results and Discussion  
### Fermentation Characteristics of Goji Juice  
As shown in Table 1, the concentration of reducing sugars was \(5521.04\pm 4.58\) mg/100 mL in the raw juice and it decreased by \(11.53\%\), \(16.61\%\), and \(28.43\%\) in the goji juice samples fermented with SLV, SZP, and SZVP, respectively, indicating that most of the saccharides present in the goji juice samples were consumed during fermentation. The saccharides in the fermented juice were utilized as carbon sources by the bacterial strains to generate lactic acid and other chemicals via a series of chemical reactions. The lactic acid concentrations were \(25.30\pm 0.71\) mg/100 mL in the raw juice, and \(316.93\pm 7.31\), \(233.8\pm 10.97\), and \(422.14\pm 6.52\) mg/100 mL in the goji juice samples fermented with SLV, SZP, and SZVP, respectively. The concentration of lactic acid was higher in the juice fermented with SZVP than the other samples. Compared with SZP, the addition of _Bacillus velezensis_ greatly enhanced the capacity to produce lactic acid. The SLV group utilized reducing sugars at a lower rate than SZP, but the concentration of lactic acid produced after fermentation was \(1.36\) times that in SZP. Thus, the strains in SLV may have directly utilize the sucrose in goji juice to produce lactic acid. These observations agree with a previous study where cashew apple juice was fermented with _Lactobacillus plantarum_, _L. acidophilus_, and _L. casei_[12], and different sugars were directly utilized by different bacteria. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Samples**} & **Reducing Sugars** & **Lactic Acid** & **Protein** & **Number of Live Bacteria** \\  & **(mg/100 mL)** & **(mg/100 mL)** & **(mg/100 mL)** & **(CFU/mL)** \\ \hline CK & \(5521.04\pm 4.58\)\({}^{\text{a}}\) & \(25.30\pm 0.71\)\({}^{\text{d}}\) & \(39.23\pm 0.67\)\({}^{\text{d}}\) & - \\ SLV & \(4884.23\pm 9.04\)\({}^{\text{b}}\) & \(316.93\pm 7.31\)\({}^{\text{b}}\) & \(74.75\pm 1.86\)\({}^{\text{b}}\) & \(8.43\times 10^{9}\) \\ SZP & \(4603.91\pm 9.35\)\({}^{\text{c}}\) & \(233.80\pm 10.97\)\({}^{\text{c}}\) & \(51.46\pm 0.35\)\({}^{\text{c}}\) & \(2.17\times 10^{10}\) \\ SZVP & \(3951.46\pm 13.73\)\({}^{\text{d}}\) & \(422.14\pm 6.52\)\({}^{\text{a}}\) & \(82.74\pm 0.31\)\({}^{\text{a}}\) & \(2.23\times 10^{10}\) \\ \hline \hline \multicolumn{5}{c}{**Sensory Quality**} \\ \cline{2-5}  & **Color** & **Flavor** & **Taste** & **Acceptability** & **Total** \\ \hline CK & \(23.50\pm 1.38\)\({}^{\text{a}}\) & \(22.83\pm 2.04\)\({}^{\text{a}}\) & \(13.83\pm 1.72\)\({}^{\text{c}}\) & \(13.20\pm 1.64\)\({}^{\text{b}}\) & \(73.17\pm 5.04\)\({}^{\text{b}}\) \\ SLV & \(23.50\pm 1.05\)\({}^{\text{a}}\) & \(21.50\pm 1.97\)\({}^{\text{a}}\) & \(23.17\pm 2.32\)\({}^{\text{a}}\) & \(16.20\pm 2.68\)\({}^{\text{a}}\) & \(84.17\pm 2.32\)\({}^{\text{a}}\) \\ SZP & \(23.00\pm 0.63\)\({}^{\text{a}}\) & \(20.67\pm 2.58\)\({}^{\text{a}}\) & \(20.33\pm 2.73\)\({}^{\text{b}}\) & \(13.80\pm 1.64\)\({}^{\text{b}}\) & \(77.50\pm 4.18\)\({}^{\text{b}}\) \\ SZVP & \(22.83\pm 0.98\)\({}^{\text{a}}\) & \(20.83\pm 2.32\)\({}^{\text{a}}\) & \(21.17\pm 1.72\)\({}^{\text{ab}}\) & \(15.20\pm 1.79\)\({}^{\text{ab}}\) & \(80.00\pm 2.97\)\({}^{\text{ab}}\) \\ \hline \hline \end{tabular}  
* CK means unfermented goji juice. SLV means goji juice fermented using _L. rhamns, L. plantarum, and _B. licheniformis_. SZVP means goji juice fermented using _L. rhamns, L. plantarum, B. licheniformis_, and _B. licheniformis_. SZVP means goji juice fermented using _L. rhamns, L. plantarum, B. vlezensis, and B. licheniformis_. The data were expressed as the mean value \(\pm\) standard deviation, except for the number of live bacteria. Data with different superscript letters (a–d) in the same column were significantly different (\(p\leq 0.05\)) and -’-’ means data not detected.  
\end{table} 
Table 1: Comparison of fermentation characteristics of each composite strain group.