# Testing Concrete for the Construction of Winemaking Tanks
## 3 Results and Discussion
### Chemical Properties
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & **Units** & **White Wine** & **Limits 1** & **DL\_C3** & **DL\_CP10** & **SL\_C3** & **SL\_CP10** & **AL\_C3** & **AL\_CP10** & **RL\_C3** & **RL\_CP10** \\ \hline pH & - & 4.01 & & 3.91 & 3.92 & 6.6 & 6.58 & 5.73 & 6.41 & 6.32 & 6.31 \\ Ca & mg/L & 21.4 & & 16.9 & 18.3 & 124.9 & 149.8 & 111 & 79.1 & 169.2 & 161.5 \\ Cr & mg/L & 0.31 & & 0.36 & 0.25 & 0.5 & 0.46 & 0.49 & 0.41 & 0.46 & 0.46 \\ Cu & mg/L & 0.18 & \textless{}1.0 & 0.25 & 0.23 & 0.56 & 0.55 & 0.42 & 0.4 & 0.45 & 0.43 \\ Fe & mg/L & 1.9 & & 2.22 & 2.6 & 10.6 & 29.2 & 17.36 & 14.84 & 15.7 & 18.6 \\ K & mg/L & 314.4 & \textless{}100 & 308.6 & 302.2 & 367.2 & 370 & 341.4 & 369 & 362.4 & 353.6 \\ Mg & mg/L & 115.2 & & 114.2 & 111 & 142.8 & 144.4 & 139.8 & 140.6 & 142.8 & 141.6 \\ Mn & mg/L & 1.81 & & 1.82 & 1.85 & 2.05 & 2.24 & 3.62 & 3.83 & 2 & 1.96 \\ Na & mg/L & 11.2 & & 14 & 12.2 & 173.8 & 175.6 & 140.8 & 392 & 99.2 & 105.4 \\ Zn & mg/L & 0.93 & \textless{}50 & 0.82 & 0.89 & 0.72 & 0.75 & 0.8 & 0.62 & 0.71 & 0.77 \\ As & \(\mu\)g/L & 12.2 & & 0.2 & ND 2 & 32.4 & 25.2 & 25.6 & 19.6 & 28.4 & 30.6 \\ Cd & \(\mu\)g/L & 0.6 & & 0.4 & ND & ND & ND & ND & ND & ND \\ Co & \(\mu\)g/L & 3 & \textless{}1000 & 3 & 3 & 28.4 & 29.8 & 15.8 & 42.2 & 22.6 & 19.2 \\ Hg & \(\mu\)g/L & ND & & ND & ND & ND & ND & ND & ND & ND \\ Ni & \(\mu\)g/L & 38.4 & \textless{}100 & 43 & 26.6 & 236.8 & 256 & 189.2 & 199.2 & 193.6 & 201.6 \\ Pb & \(\mu\)g/L & ND & \textless{}5000 & ND & ND & ND & ND & ND & ND & ND \\ Se & \(\mu\)g/L & 0.4 & & 10 & 4.4 & 5.8 & 4.6 & 4.4 & 5.8 & 4 & 5.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: Determination of metals and pH value of white wine, after 30 days immersion of concrete in white wine. According to [PERSON] et al. [4], wine acidity is a characteristic that is affected by the type of vessel or the container of the fermentation. In the present study, the pH value of wines is modified and seems to vary depending on the different coatings of the concrete tank, as depicted in Tables 9 and 10. Coating D offered the least modification of wine pH and the least leaching of metals in the wine bulk. Figure 4: Diffractograms of tested concretes C3 and CP10 before and after immersion in white (L) and red (K) wine, where F: phlogopite, E: ettrinigite, B: albite, Q: quartz, P: portlandite, C: calcite, M: microcline, Ch: chlorite. The influence of red wine on coated and plain concrete was slightly different compared to white wine. The leaching of potassium in red wine was found to be significant. Potassium concentration after the immersion of concrete samples was found to be more than two times greater. Also, sodium was leached to a higher degree in S and A coatings, compared to white wine influence. The increase in Ca and K concentration in wine indicates the leachability of calcium hydroxide and potassium oxide. At the same time, this phenomenon leads to an increase in the pH of the wine due to the dilution of hydroxyl ions (OH\({}^{-}\)), for both the white and red wine effect on the samples, except for coating D. In contrast, the decrease in magnesium and manganese concentration in the wine following concrete immersion indicates the potential absorption of these metals in the pores of the concrete. The metals identified in trace amounts, at concentrations of the order of magnitude of \(\mu\)g/L, do not show significant variations, except for chromium (Cr) and nickel (Ni), which are absent from the wine and were found in the wine after contact with the concrete for 30 days. Nickel concentration meets the standards of water intended for human consumption, following the European Directive 2020/2184 [33]. According to the European Regulation 2023/915 [34], for maximum permitted levels for food contaminants, the metals of interest are lead (Pb), cadmium (Cd), mercury (Hg), tin (Sn) and arsenic (As). After the leachability test, Pb, Cd and Hg concentrations were below the limit of detection in \(\mu\)g/L, against the regulation that limits to 0.02 to 0.05 mg/kg.