## 3 Results and Discussion
### Reduction in Microbial Counts and Shelf Life of Juice
\begin{table}
\begin{tabular}{c c c c c} \hline \hline  & & & \multicolumn{3}{c}{**Time Storage (h)**} \\ \hline \multirow{2}{*}{**Quality Parameters**} & \multirow{2}{*}{**Juice Sample Codes**} & \multirow{2}{*}{**24**} & \multirow{2}{*}{**48**} & \multirow{2}{*}{**72**} \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\ \hline \multirow{6}{*}{**C**} & \multirow{6}{*}{**C**} & \multirow{6}{*}{6.24 \(\pm\) 0.12  & \multirow{6}{*}{6.24 \(\pm\) 0.12  \\  & & & & \\  & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Evaluation of the total number of microorganisms and yeasts of control carrot juice and juice samples treated with cold atmospheric plasma and/or supplemented with sumac after 24, 48, and 72 h of refrigerated storage (6 \({}^{\circ}\)C). after 72 h of storage. Compared to the control, the total number of aerobic microorganisms decreased in samples SP05 and P+05S by 4.76 and 5.00 log\({}_{10}\) CFU/mL, respectively, and the yeast count after this storage time was reduced below the limit of detection. The application of the higher amount of sumac powder in the SP3 and P+3S combinations extended the microbiological shelf life of the unpasteurized carrot juice to 72 h. The total number of microorganisms and yeasts after 24, 48 and 72 h of refrigerated storage was below the limit of detection (1 log\({}_{10}\) CFU/mL). The present results clearly indicate that the cold plasma treatment and the natural sumac powder addition have a decontaminating effect on the microbial load of carrot juice. Similar research results reporting the ability of cold plasma to inactivate harmful microorganisms in beverages have been described in many publications [12; 35; 36; 37; 38]. In the [PERSON] et al. [12] publication, 5 minutes of plasma treatment generated in the GlidArc reactor (where the process gas was air) enabled 3.45, 3.55 log and 3.32 log\({}_{10}\) CFU/mL reductions just after the treatment for the total aerobic mesophilic bacteria colonies, yeast and molds, respectively. It has also been proved that sumac (_Rlus coriaria_ L) fruit extract has inhibitory activity against the growth of food spoilage and/or pathogenic bacteria, especially _Bacillus cereus_, _Escherichia coli_, _Pseudomonas aeruginosa_, _Bacillus subtilis_, _Staphylococcus aureus_, _Penicillium_ sp., and _Apergillus niger_[39; 40; 41; 42]. Sumac can be considered a natural antimicrobial protreatment against a number of microorganisms found in food. [PERSON] and [PERSON] [43] used aqueous sumac extracts to improve the microbiological quality of silver carp fillets. After 18 days of refrigerated storage, they observed a decrease in the amount of total viable organism from 9.01 to 7.34 log\({}_{10}\) CFU/g and total psychrophilic count from 8.97 to 7.21 log\({}_{10}\) CFU/g in products treated with 5% sumac extract in comparison with control samples. Carrot juice supplementation with ground sumac in amounts of 0.5, 1.5 and 3 g/100 mL caused (at 72 h of testing) a reduction in the total number of microorganisms by 1.7, 2.9 and 3.1 log\({}_{10}\) CFU/g, respectively, compared to the control [44]. The quality of juice during storage can be improved with methods based on the use of more than one preserving factor: acidification with sonication, pulsed electric field with sonication, sonication with high-voltage cold plasma treatment, and pulsed electric field combined with temperature and natural preservatives [45; 46; 47; 48]. Importantly, the combination of plasma treatment with the sumac powder addition to the freshly pressed carrot juice was analyzed here for the first time and yielded high-quality products that were suitable for consumption (from the microbial load point of view), even after 72 h refrigerated storage.