## 3 Results and Discussion  
### Characteristics of the Fermented Hemp Seed Products  
Table 1 presents the main characteristics regarding the efficiency of fermentation, namely the LAB count, pH, TTA, and acetic (volatile acidity) and lactic acid contents. Organic acids, primarily lactic and acetic acids, produced by LAB are the dominant metabolites that affect the acidity of the fermentation medium. These acids are known to play a crucial role in reducing pH, thereby influencing the bioactivity and antimicrobial properties of the fermented product. After fermentation for 48 h, the LAB count was \(>\)10\({}^{9}\) CFU/g, confirming the suitability of hemp seed flour for LAB fermentation. The acidity of the fermented hemp seed products depended on the LAB strain used for fermentation. The hemp seeds fermented with _L. plantarum_ presented the highest TTA and the lowest pH. The TTA of the hemp seed product fermented with _L. plantarum_ was 79% higher than the TTA of the hemp seed product fermented with _L. brevis_ and 32% higher than hemp seed product fermented with _L. acidophilus_. The TTA, pH, and LAB count results confirm the suitability of hemp seed flour for LAB propagation and for untraditional sourdough production, which can be applied for bread making. [PERSON] et al. [28] reported wheat sourdough with a higher pH (4.77-5.17) and a lower TTA (3.47-4.5 mL of 1 M NaOH) compared with the present study. Typically, the sourdough pH is \(<\)4.5, while the TTA strongly depends on the type of flour and the applied starter culture. Usually, the TTA of wheat sourdough is 8-13 mL of 1 M NaOH [29; 30]. \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Unfermented Hemp** & **L. plantarum MR24** & **L. brevis R26** & **L. acidophilus DSM** \\ \hline LAB count, CFU/g & - & (7.9 \(\pm\) 0.1)\(\cdot\)10\({}^{9}\) b & (3.3 \(\pm\) 0.1)\(\cdot\)10\({}^{9}\) a & (2.9 \(\pm\) 0.2)\(\cdot\)10\({}^{9}\) c \\ \hline \multicolumn{5}{c}{Acidity} \\ \hline pH & 6.65 \(\pm\) 0.1 d & 4.72 \(\pm\) 0.03 a & 5.52 \(\pm\) 0.14 c & 4.92 \(\pm\) 0.01 b \\ TTA & 2.6 \(\pm\) 0 a & 6.1 \(\pm\) 0.02 d & 3.4 \(\pm\) 0.07 b & 4.6 \(\pm\) 0.21 c \\ Volatile acidity & 0.4 \(\pm\) 0.04 a & 1.68 \(\pm\) 0.06 c & 2.28 \(\pm\) 0.07 d & 1.08 \(\pm\) 0.01 b \\ \hline \multicolumn{5}{c}{Lactic acid content} \\ \hline \multicolumn{5}{c}{Lactic acid, g/kg} \\ \hline \multicolumn{5}{c}{Enzymatic activities} \\ \hline Cellulose activity, & - & 1.466 \(\pm\) 0.188 a & 1.170 \(\pm\) 0.183 a & - \\ Cumylase activity, AU/g & 0.290 \(\pm\) 0.041 b & 0.149 \(\pm\) 0.001 a & 0.721 \(\pm\) 0.001 c & 0.242 \(\pm\) 0.048 b \\ Phytase activity, PhU/g & 0.140 \(\pm\) 0.005 b & 0.138 \(\pm\) 0.003 b & 0.191 \(\pm\) 0.027 c & 0.097 \(\pm\) 0.004 a \\ Protease activity, PU/g & 0.043 \(\pm\) 0.004 a & - & 0.668 \(\pm\) 0.067 c & 0.284 \(\pm\) 0.006 b \\ \hline \multicolumn{5}{c}{TPC and antioxidant activity} \\ \hline TPC, GAE mg/100 g & 13.0 \(\pm\) 0.2 a & 18.9 \(\pm\) 0.1 b & 65.6 \(\pm\) 0.2 d & 25.9 \(\pm\) 1.8 c \\ \hline Antioxidant activity, & 25.0 \(\pm\) 1.1 b & 8.1 \(\pm\) 2.3 a & 47.0 \(\pm\) 2.5 c & 9.6 \(\pm\) 2.8 a \\ mg TE/100 g & & & & \\ \hline \hline \end{tabular} The values in a row with different characters (a–d) are significantly different (\(p<0.05\)).  
\end{table} 
Table 1: The characteristics of the hemp seeds after fermentation for 48 h.  
During fermentation, carbohydrates are broken down to form lactic acid, which acidifies the media and thus reduces the pH. Unfermented hemp seed flour had the lowest lactic acid content and volatile acidity (which represents the acetic acid content). The mean lactic acid content of the fermented hemp seed products was 9.27-11.98 g/kg. This content is 2 times higher compared with the study by [PERSON] et al. [31], who reported a lactic acid content of 3.0-5.5 g/kg in wheat sourdough produced with _L. plantarum_ and _Leuconostoc_ starters. Fermentation with each tested LAB strain led to unique enzymatic changes of the fermented hemp seed product (Table 1). Fermentation with _L. plantarum_ and _L.