## 4 Conclusions  
Apple quality is influenced by color, sugar content and acid composition. A ready-to-eat product, apple chips were produced from three different apple cultivars by drying. Apple chips preserved the good color, and it can be concluded, after analyzing the color parameters, that samples F1, G1 and S1 are closer to the color of fresh apple samples, followed by samples S2, G2 and F2. The drying of the apple chip samples in the dehydrator leads to a decrease in the values of water activity, which varied between 50 and 60% compared to the \(aw\) of the fresh samples, while for the samples obtained in the oven, the \(aw\) values decreased and varied between 28 and 30%. During storage, samples of apple chips dried in the oven are less influenced in terms of water activity, and the increase in \(aw\) values is smaller compared to the values obtained for samples from the dehydrator, except for the samples of the 'Golden Delicious' cultivar. Instead, it was observed that during apple chips storage, \(aw\) does not exceed the value 0.6, except for a single sample S1. During storage, \(TA\) values increased more for apple samples obtained in the oven (10.00-16.35%) than for those obtained in the dehydrator (5.33-12.35%), while \(TSS\) values decreased and varied from 34.11 (G2) to 42.87% (F2) (apple chips obtained in the dehydrator) and from 18.79 (S1) to 38.72% (F1) for apple chips obtained in the oven. After analyzing all the results obtained regarding the physico-chemical parameters and the sensory analysis, it can be concluded that the apple chips obtained by drying in a dehydrator on the first day are the most appreciated in the following order: S2, F2 and G2, followed by F1, G1 and S1; after twenty-one days, the order changes in the following way: F2 \(>\) G2 \(>\) G1 \(>\) S2 \(>\) F1 \(>\) S1. \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline  & \(M\) & \(aw\) & \(pH\) & \(TA\) & \(TSS\) & \(EC\) & \(L^{\star}\) & \(a^{\star}\) & \(b^{\star}\) & \(\Delta E\) & \(BI\) \\ \hline \(aw\) & 0.473 & & & & & & & & & & \\ \(pH\) & \(-\)0.571 & 0.453 & & & & & & & & \\ \(TA\) & \(-\)0.373 & \(\mathbf{-0.994}\) & \(-\)0.549 & & & & & & & \\ \(TSS\) & 0.485 & \(-\)0.541 & \(\mathbf{-0.995}\) & 0.631 & & & & & & \\ \(EC\) & 0.819 & \(-\)0.119 & \(\mathbf{-0.939}\) & 0.228 & 0.899 & & & & & \\ \(L^{\star}\) & \(\mathbf{0.988}\) & 0.331 & \(-\)0.692 & \(-\)0.225 & 0.615 & 0.898 & & & & \\ \(a^{\star}\) & \(\mathbf{-0.964}\) & \(-\)0.222 & 0.769 & 0.113 & \(-\)0.700 & \(\mathbf{-0.942}\) & \(\mathbf{-0.994}\) & & & \\ \(b^{\star}\) & 0.879 & 0.836 & \(-\)0.110 & \(-\)0.771 & 0.008 & 0.445 & 0.794 & \(-\)0.72 & & \\ \(\Delta E\) & \(\mathbf{-0.930}\) & \(-\)0.116 & 0.833 & 0.006 & \(-\)0.772 & \(\mathbf{-0.972}\) & \(\mathbf{-0.976}\) & \(\mathbf{0.994}\) & \(-\)0.641 & \\ \(BI\) & \(-\)0.820 & 0.116 & \(\mathbf{0.938}\) & \(-\)0.225 & \(-\)0.898 & \(\mathbf{-0.999}^{\star}\) & \(-\)0.899 & \(\mathbf{0.943}\) & \(-\)0.447 & \(\mathbf{0.973}\) \\ \(WI\) & \(\mathbf{0.942}\) & 0.149 & \(-\)0.814 & \(-\)0.039 & 0.751 & 0.964 & \(\mathbf{0.982}\) & \(\mathbf{-0.997}^{\star}\) & 0.666 & \(\mathbf{-0.999}^{\star}\) & \(\mathbf{-0.965}\) \\ \hline \end{tabular} \({}^{\star}\)Statistically significant at \(p\) \(<\) 0.05. Values in bold show very high positive/negative correlation (according to [PERSON] [68]).  
\end{table} 
Table 4: Correlations between physico-chemical parameters measured or calculated for apple chips dried in dehydrator (Pearson correlation). Overall, this study concludes that the apple cultivar must also be considered in order to obtain apple chips, not just the dehydration method. Conceptualization, C.G. and A.E.P. ; methodology, C.G. and A.E.P. ; software, C.G. ; validation, C.G., A.E.P. and A.L. ; formal analysis, C.G. and A.E.P. ; investigation, C.G. and A.E.P. ; resources, C.G. and A.E.P. ; writing--original draft preparation, C.G. ; writing--review and editing, C.G., A.E.P. and A.L. ; supervision, A.L. ; funding acquisition, C.G.