## Materials and Methods
### Vinegar Production from FSS
#### 2.3.3 Vinegar Production Using Immobilized or Free AAB Cultures  
Delignified cellulosic material (DCM) was used as the cell immobilization carrier. It was prepared by boiling pine sawdust with NaOH solution as described before [10; 11]. For vinegar production, acidification of 400 mL of the sweet FSS wine with 400 mL of the mixed AAB culture, was carried out at 30 \({}^{\circ}\)C, 250 rpm agitation speed, and 500 cm\({}^{3}\)/min air supply (Elite 803 air pump; Rolf C. Hagen UK Ltd., Castleford, UK) (Figure 1). Amounts of 100 g DCM, 2.16 g (NH4)\({}_{2}\)SO4 and 0.48 g KH\({}_{2}\)PO4 were added to the mixture. The fermentations were carried out until vinegar with a titratable acidity of about 40 g/L was produced. At this point, 400 mL of produced vinegar was removed and 400 mL FSS wine, 2.16 g (NH4)\({}_{2}\)SO4, and 0.48 g KH\({}_{2}\)PO4 were added. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Culture**} & **Initial** & **Initial** & **Accification** & **Final Acidity** & **Residual** & **Residual** \\  & **Sugar** & **Ethanol** & **Time \({}^{*}\)** & **Final Acidity** & **Sugar** & **Ethanol** \\ \hline  & **(\% _w/v_)** & **(\% _v/v_)** & **(Days)** & **(g Acetic Acid/L)** & **(\% _w/v_)** & **(\% _v/v_)** \\ \hline  & & & & Wild AAB culture & & \\ FCW & 2.61 \(\pm\) 0.37 \({}^{\mathrm{a}}\) & 4.73 \(\pm\) 0.25 \({}^{\mathrm{a}}\) & \textgreater{}3 & 55.07 \(\pm\) 2.39 \({}^{\mathrm{a}}\) & 0.31 \(\pm\) 0.06 \({}^{\mathrm{a}}\) & 0.40 \(\pm\) 0.53 \({}^{\mathrm{a}}\) \\ ICW & 3.03 \(\pm\) 0.17 \({}^{\mathrm{b}}\) & 4.30 \(\pm\) 1.22 \({}^{\mathrm{a}}\) & \textgreater{}5 & 49.54 \(\pm\) 0.99 \({}^{\mathrm{b}}\) & 1.48 \(\pm\) 0.10 \({}^{\mathrm{b}}\) & 0.90 \(\pm\) 0.85 \({}^{\mathrm{a}}\) \\ FCW-2M & 3.03 \(\pm\) 0.03 \({}^{\mathrm{a}}\) & 5.83 \(\pm\) 1.84 \({}^{\mathrm{a}}\) & \textgreater{}20 & 39.97 \(\pm\) 2.82 \({}^{\mathrm{c}}\) & 0.50 \(\pm\) 0.13 \({}^{\mathrm{a}}\) & 0.78 \(\pm\) 0.69 \({}^{\mathrm{a}}\) \\ ICW-2M & 3.80 \(\pm\) 0.22 \({}^{\mathrm{b}}\) & 6.11 \(\pm\) 1.41 \({}^{\mathrm{a}}\) & \textgreater{}10 & 47.44 \(\pm\) 1.81 \({}^{\mathrm{b}}\) & 1.47 \(\pm\) 0.31 \({}^{\mathrm{b}}\) & 1.56 \(\pm\) 0.32 \({}^{\mathrm{a}}\) \\ \hline  & & Mixed AAB culture (_A. aceti_ and _[PERSON]. [PERSON]_) & & & \\ FCM & 4.03 \(\pm\) 0.46 \({}^{\mathrm{b}}\) & 4.85 \(\pm\) 0.19 \({}^{\mathrm{a}}\) & \textgreater{}9 & 49.00 \(\pm\) 2.01 \({}^{\mathrm{b}}\) & 1.65 \(\pm\) 0.55 \({}^{\mathrm{b}}\) & 1.39 \(\pm\) 1.22 \({}^{\mathrm{a}}\) \\ ICM & 3.88 \(\pm\) 0.03 \({}^{\mathrm{b}}\) & 4.12 \(\pm\) 1.49 \({}^{\mathrm{a}}\) & \textgreater{}2 & 48.77 \(\pm\) 1.83 \({}^{\mathrm{b}}\) & 2.55 \(\pm\) 0.21 \({}^{\mathrm{c}}\) & 0.58 \(\pm\) 0.43 \({}^{\mathrm{a}}\) \\ FCM-2M & 4.03 \(\pm\) 0.79 \({}^{\mathrm{b}}\) & 4.75 \(\pm\) 0.56 \({}^{\mathrm{a}}\) & \textgreater{}11 & 41.57 \(\pm\) 0.81 \({}^{\mathrm{c}}\) & 1.25 \(\pm\) 0.09 \({}^{\mathrm{b}}\) & 0.34 \(\pm\) 0.42 \({}^{\mathrm{a}}\) \\ ICM-2M & 4.05 \(\pm\) 0.07 \({}^{\mathrm{b}}\) & 5.93 \(\pm\) 0.64 \({}^{\mathrm{a}}\) & \textgreater{}7 & 42.66 \(\pm\) 7.32 \({}^{\mathrm{b}}\) & 2.99 \(\pm\) 0.06 \({}^{\mathrm{d}}\) & 1.08 \(\pm\) 0.19 \({}^{\mathrm{a}}\) \\ \hline \hline \end{tabular} FCW, ICW: Free and immobilised cells of wild culture, respectively. FCM, ICM: Free and immobilised cells of selected, mixed culture, respectively. 2M: 2-Month storage at 4 \({}^{\circ}\)C. \({}^{*}\)Time when the acidity levels tend to reach a plateau. Different superscript letters in the same column indicate statistically significant differences.  
\end{table} 
Table 1: Kinetic parameters of the sweet FSS wine acidification process using the wild and the pure, mixed AAB cultures, free and immobilized on DCM. In the same manner, vinegar production was carried out using, immobilized and free cells of both the wild AAB culture and the selected, mixed _A. aceti_ and _K. europaeus_ culture. For comparison, vinegar fermentations using free cells (wild or selected AAB cultures), without the addition of DCM, were also carried out.