## 3 Results and Discussion
### Cell Viability
\begin{table}
\begin{tabular}{c c c c c} \hline \hline
**ISC** & **Time** & \multicolumn{3}{c}{**Cell Counts**} \\ \hline  & & _L. paracasei_ SP5 & **Yeasts and Fungi** & **Coliforms** \\ \hline
**g/L** & & & **Log cfu/mL** & \\ \hline  & 48 h & 7.2 \(\pm\) 0.11 \({}^{\mathrm{c}}\) & nd & nd \\  & 1 st week & 9.1 \(\pm\) 0.08 \({}^{\mathrm{a}}\) & nd & nd \\
61.0 & 2 nd week & 9.3 \(\pm\) 0.13 \({}^{\mathrm{a}}\) & nd & nd \\  & 3 rd week & 8.2 \(\pm\) 0.12 \({}^{\mathrm{b}}\) & nd & nd \\  & 4 th week & 6.5 \(\pm\) 0.12 \({}^{\mathrm{d}}\) & nd & nd \\ \hline  & & & nd & nd \\  & 48 h & 9.5 \(\pm\) 0.07 \({}^{\mathrm{b}}\) & nd & nd \\
40.3 & 1 st week & 10.1 \(\pm\) 0.05 \({}^{\mathrm{a}}\) & nd & nd \\  & 2 nd week & 10.1 \(\pm\) 0.12 \({}^{\mathrm{a}}\) & nd & nd \\  & 3 rd week & 9.1 \(\pm\) 0.05 \({}^{\mathrm{c}}\) & nd & nd \\  & 4 th week & 7.9 \(\pm\) 0.05 \({}^{\mathrm{d}}\) & nd & nd \\ \hline  & & & nd & nd \\
28.8 & 48 h & 7.4 \(\pm\) 0.11 \({}^{\mathrm{c}}\) & nd & nd \\  & 1 st week & 8.5 \(\pm\) 0.12 \({}^{\mathrm{b}}\) & nd & nd \\  & 2 nd week & 9.5 \(\pm\) 0.10 \({}^{\mathrm{a}}\) & nd & nd \\  & 3 rd week & 7.5 \(\pm\) 0.11 \({}^{\mathrm{c}}\) & nd & nd \\  & 4 th week & 5.1 \(\pm\) 0.12 \({}^{\mathrm{d}}\) & nd & nd \\ \hline \hline \end{tabular} \({}^{\mathrm{a}}\)-\({}^{\mathrm{d}}\) Different superscript letters in columns for the same ISC indicate statistically significant differences (multifactor (MF)-ANOVA with [PERSON]’s honestly significant difference (HSD) multiple range test), nd: not detected (no visible colony or less than 10 cfu/mL).  
\end{table} 
Table 1: Viability of the potential probiotic strain _Lactobacillus paraasei_ SP5 in the fermented chicken-berry juice at 30 \({}^{\circ}\)C in different initial sugar concentrations (ISC) after 48 h and 4 weeks. two juices contained viable cells above 6.5 log cfu/mL. These recorded viability values were detected above the limit of 6 log cfu/mL, which is the limit required for products to be characterized as probiotic [13; 25]. Likewise, between the two juices with initial concentrations of sugars of 40.3 and 60.1 g/L, the second one had significantly higher probiotic load at the last week of of fermentation at 4 \({}^{\circ}\)C (7.9 log cfu/mL) and thus it was chosen for the rest of the experiments. Increased numbers of viable cells in a food system, especially during storage, is critical for candidate probiotic microorganisms [7; 13]. The stability observed in the viability of _L. paracasei_ SP5 during fermentation at 4 \({}^{\circ}\)C of chokeberry juice (with initial sugar concentration of 40.3 g/L) was quite encouraging. The preservation of cell viability was also reported in other cases during lactic acid fermentation of fruit juices, even at fermentation at 4 \({}^{\circ}\)C. Specifically, experiments conducted with pomerangate juice and cornelian cherry juice fermented with other candidate probiotic _L. paracasei_ strains provided high viability levels during fermentation at 4 \({}^{\circ}\)C [7; 11; 12]. A possible explanation of this outcome is that these LAB strains are very tolerant and can maintain high viability levels at low temperatures [7; 11; 33]. Moreover, other compounds existing in fruit juices may exhibit prebiotic properties and promote the growth of LAB [13]. For instance, it has been reported that anthocyanins from black rice can provide prebiotic properties and promote the growth of on Bifidobacterium and Lactobacillus [34]. Another factor ensuring viability of _L. paracasei_ SP5 in fermented chokeberry juice is its tolerance in low pH values. As reported previously, _L. paracasei_ SP5 is considered a potentially probiotic strain due to its ability to succeed in various in vitro tests with low pH tolerance being a significant one. In more detail, _L. paracasei_ SP5 managed to preserve its viability during exposure in a pH value of 3 [25].