## 3 Results and Discussion  
### Physicochemical Analysis  
The results from the physicochemical analysis are summarized in Table 1. Firstly, the TSSC increased gradually compared with the fresh sample (\(\approx\)14 \({}^{\circ}\)Brix), with 31, 45, and 55 \({}^{\circ}\)Brix along the cycles. The TSSC at each cycle were superior to those obtained in previous studies under comparable conditions in our laboratory with fruit juices such as orange juice [14], pineapple juice [20], and blueberry juice [28], in which the final concentration values were approximately 40, 36, and 33 \({}^{\circ}\)Brix at the third cycle, respectively. Similarly, the TSSC results were higher than those reported by [PERSON] et al. [29], [PERSON] et al. [30], [PERSON] et al. [31] and [PERSON] et al. [32], in which orange juice, coffee extract, and apple juice were cryoconcentrated by falling-film (FFCC), BCC, and SCC, respectively. Despite the values in our study, SCC, FFCC, and PCC have more advanced technological development than BCC. So, future studies could focus on block cryoconcentration at semi-industrial scale or pilot-plant scale. In addition, the results reflected an increase over 2.3, 3.2, and 4.0 times, in concentration index (CI, ratio C\({}_{\text{s}}\)/C\({}_{0}\)) terms, from the first to the third cycle, respectively. Therefore, the difference in the TSSC results could be assigned to the sized tubes that contained the liquid samples. Concretely, in our studies, we used a 50 mL-tube (45 mL sample). Besides, the temperature used, i.e., -20 \({}^{\circ}\)C allows a moderate freezing propagation on the samples. Thus, these three conditions promote a better movement of the solids in the freezing step and favors the separation of solutes from the ice fraction during thawing [17]. The solutes occluded in the ice phase (C\({}_{\text{i}}\)) presented values close to 6, 10, and 15 \({}^{\circ}\)Brix as the CBCC cycles progressed (data not shown). Thus, in CI terms, the C\({}_{\text{s}}\) presented an increase of 0.4, 0.7, and 1.1 times with regard to the first, second, and third cycle, respectively. This behavior could be comparable with CBCC studies applied to orange juice [19] and blueberry juice [28]. However, the C\({}_{\text{i}}\) results were better (purest ice samples) than those reported by [PERSON] et al. [28] in the cryoconcentration of \begin{table}
\begin{tabular}{c c c c c} \hline  & **Fresh Juice** & \begin{tabular}{c} **CBCC** \\ **Cycle 1** \\ \end{tabular} & \
\begin{tabular}{c} **CBCC** \\ **Cycle 2** \\ \end{tabular} &
\begin{tabular}{c} **CBCC** \\ **Cycle 3** \\ \end{tabular} \\ \hline TSSC (\({}^{\circ}\)Brix) & \(13.9\pm 1.0^{\text{d}}\) & \(31.4\pm 1.9^{\text{e}}\) & \(44.7\pm 1.7^{\text{b}}\) & \(54.9\pm 0.7^{\text{a}}\) \\ pH & \(3.5\pm 0.0^{\text{a}}\) & \(3.4\pm 0.0^{\text{b}}\) & \(3.3\pm 0.0^{\text{c}}\) & \(3.1\pm 0.0^{\text{d}}\) \\ TTA (g malic acid/L) & \(2.3\pm 0.0^{\text{d}}\) & \(2.5\pm 0.0^{\text{c}}\) & \(2.8\pm 0.0^{\text{b}}\) & \(3.0\pm 0.1^{\text{a}}\) \\ \(\rho\) (g/mL) & \(1.1\pm 0.0^{\text{d}}\) & \(1.2\pm 0.0^{\text{c}}\) & \(1.4\pm 0.0^{\text{b}}\) & \(1.5\pm 0.0^{\text{a}}\) \\ Color & & & & \\ L* & \(78.1\pm 1.3^{\text{a}}\) & \(76.9\pm 3.0^{\text{a}}\) & \(68.1\pm 1.9^{\text{b}}\) & \(68.4\pm 0.4^{\text{b}}\) \\ a* & \(3.9\pm 0.2^{\text{c}}\) & \(6.1\pm 1.6^{\text{b}}\) & \(10.9\pm 0.9^{\text{a}}\) & \(11.0\pm 0.6^{\text{a}}\) \\ b* & \(27.7\pm 0.4^{\text{c}}\) & \(38.9\pm 4.7^{\text{b}}\) & \(41.1\pm 2.2^{\text{a}}\) & \(43.5\pm 3.7^{\text{a}}\) \\ \(\Delta\)E* & - & \(11.6\pm 0.2^{\text{c}}\) & \(17.2\pm 0.1^{\text{b}}\) & \(25.0\pm 0.0^{\text{a}}\) \\ \hline \end{tabular} \({}^{1}\) Within each row, a, b, c, d when there are no significant differences (\(p\leq 0.05\)), are identified by the same superscript letter, according to a LSD test.  
\end{table} 
Table 1: Physicochemical properties of apple fresh juice and cryoconcentrated samples at each cycle\({}^{1}\).