## 3 Results and Discussion
### Effect of Coatings on the Color of Fresh-Cut Parsley during Storage  
Table 3 presents the parameters of the colors of the uncoated and coated fresh-cut root parsley. It can be observed that the analyzed parsley was characterized by a high color brightness stability, parameter L* changed slightly during storage, and the positive effect of the coating containing jojoba oil can be observed as a result of the emulsion-based character of the coatings [8]. When analyzing the changes in the color, the brightening of the parsley rings was noticed after 28 days of storage compared to day 0. Moreover, after 14 and 21 days of storage, a high proportion of the tested parsley samples was characterized by a yellow color (parameter b*). When examining the effect of the storage time on parameter changes a*, no statistically significant differences were found, except for in the case of the parsley coated with the whey protein isolate. However, in the remaining parsley samples, these differences were statistically significant. The statistical analysis showed that the protein coatings affected the changes in the value of parameter a*. During storage, no significant changes in the shade of the color were observed, which corresponds to the color tone, spanning the entire storage period at a level of approx. 86\({}^{\circ}\) in all tested samples. It was also shown that the type of edible coating used did not have a significant effect on the changes in the value of the color tone angle (\(p<0.05\)), but it was found that the storage time significantly influenced the changes in the color tone angle. No statistically significant differences were observed in the samples coated with the whey protein isolate. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Storage Time** **(Days)**} & \multicolumn{4}{c}{**Hardness (N)**} \\ \cline{2-5}  & \multicolumn{4}{c}{**Type of Material**} \\ \cline{2-5}  & **Control** & **WPI** & **WPI\_JO\_1\%** & **WPI\_JO\_2\%** \\ \hline
**0** & \(59.32\pm 4.54\)\({}^{\text{ab,B}}\) & \(59.88\pm 4.41\)\({}^{\text{b,B}}\) & \(56.28\pm 4.26\)\({}^{\text{ab,AB}}\) & \(52.17\pm 5.43\)\({}^{\text{a,A}}\) \\
**7** & \(64.34\pm 4.52\)\({}^{\text{b,A}}\) & \(63.73\pm 6.78\)\({}^{\text{b,A}}\) & \(68.76\pm 7.42\)\({}^{\text{c,A}}\) & \(69.44\pm 7.48\)\({}^{\text{bc,A}}\) \\
**14** & \(60.84\pm 7.97\)\({}^{\text{b,A}}\) & \(58.82\pm 5.86\)\({}^{\text{b,A}}\) & \(63.82\pm 8.78\)\({}^{\text{ab,A}}\) & \(62.55\pm 7.57\)\({}^{\text{b,A}}\) \\
**21** & \(63.43\pm 7.59\)\({}^{\text{b,AB}}\) & \(71.05\pm 7.66\)\({}^{\text{c,B}}\) & \(55.22\pm 6.19\)\({}^{\text{a,A}}\) & \(72.28\pm 6.78\)\({}^{\text{c,B}}\) \\
**28** & \(50.98\pm 4.39\)\({}^{\text{a,A}}\) & \(48.33\pm 5.29\)\({}^{\text{a,A}}\) & \(66.23\pm 8.48\)\({}^{\text{bc,B}}\) & \(60.49\pm 5.01\)\({}^{\text{ab,B}}\) \\ \hline \hline \end{tabular} Mean values with standard deviations in brackets. Different superscript letters (\({}^{\text{a,e}}\)) within the same column or (\({}^{\text{A,B}}\)) within the lines indicate significant differences between the samples (\(p<0.05\)).  
\end{table} 
Table 2: The hardness of samples uncoated (control) and coated with whey protein isolate (WPI) coatings incorporated with jojoba oil (JO) of fresh-cut root parsley during storage. According to the conducted research, the highest value of the L* parameter was achieved for the control sample (85.33) after 28 days of storage, although there were no large differences in the measurement values of the other parsley samples tested. Taking into account the samples coated with the whey protein isolate with the addition of jojoba oil at concentrations of 1 and 2%, in contrast to the uncoated samples and those coated with the isolate alone, the storage time was characterized by no statistically significant differences (\(p<0.05\)). The type of applied coating significantly influenced the brightening of the parsley rings, as evidenced by the performed statistical analysis. The value of the L* parameter is an important indicator of the attractiveness of vegetables and fruits.