## 3 Results and Discussion
### Selecting Multiple Starter Candidates for AAF  
In liquid medium containing 5% alcohol, six AABs showed optimal growth when fermented at 30 \({}^{\circ}\)C for 15 days. In particular, GV-12 and GV-17 showed high acid-producing ability and alcohol tolerance in 8% alcohol. Moreover, GV-8 and GV-22 showed high acid-producing ability at pH 4.0. Therefore, the GV-8, GV-12, GV-17, and GV-22 strains were selected as multiple starter candidates for AAF and were named A, B, C, and D, respectively (Table 1). \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Cane. EtOH**} & \multicolumn{1}{c}{**Status Activity According to Fennectation Period (Ops)**} & \multicolumn{1}{c}{**Caveon LOD. **} & \multicolumn{1}{c}{**Academicity to Fennectation Period (Ops)**} & \multicolumn{1}{c}{**Caveon LOD. **} & \multicolumn{1}{c}{**Academicity to Fennectation Period (Ops)**} \\ \hline \multirow{5}{*}{**Cave. **} & \multicolumn{1}{c}{G/S-5} & \multicolumn{1}{c}{12.7 \(\pm\) 0.03\({}^{\circ}\)} & \multicolumn{1}{c}{2.2 \(\pm\) 0.03\({}^{\circ}\)} & \multicolumn{1}{c}{3.5 \(\pm\) 0.03\({}^{\circ}\)} & \multicolumn{1}{c}{4.5 \(\pm\) 0.04\({}^{\circ}\)} & \multicolumn{1}{c}{5.9 \(\pm\) 0.05\({}^{\circ}\)} & \multicolumn{1}{c}{5.6 \(\pm\) 0.03\({}^{\circ}\)} & \multicolumn{1}{c}{0. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c c c c c c} \hline \hline \multicolumn{1}{c}{**Initial pH \({}^{\dagger}\)**} & \multicolumn{1}{c}{**Status**} & \multicolumn{1}{c}{**Methods Ability Aocking Pennennation Period (Dups)**} & \multicolumn{1}{c}{**Caustic (OD  
Changes in Titractable Acidity and Growth of Multiple AAB According to Fermentation Temperature and Initial pH  
Titractable acidity and growth were measured in a liquid medium containing 5% alcohol and fermented at various temperatures (20, 30, and 40 \({}^{\circ}\)C) for 27 days to evaluate the optimal growth conditions and investigate the acid-producing ability of multiple AAB according to the fermentation environment (Figure 1). The seven multiple AAB starters were as follows: AB (_A. ascendens_ GV-8 and _A. ascendens_ GV-12), AC (_A. ascendens_ GV-8 and _A. pasteuranus_ GV-17), AD (_A. ascendens_ GV-8 and _A. pasteuranus_ GV-22), BC (_A. ascendens_ GV-12 and _A. pasteuranus_ GV-17), BD (_A. ascendens_ GV-12 and _A. pasteuranus_ GV-22), CD (_A. pasteuranus_ GV-17 and _A. pasteuranus_ GV-22), and ABCD (mixture of A, B, C, and D starters; control). Multiple AAB showed the highest increase in the tittatable acidity and growth at 30 \({}^{\circ}\)C, similar to single AAB (Figure 1b,e). After 27 days at 30 \({}^{\circ}\)C, the average tittatable acidity of six AABs was 4.78 \(\pm\) 0.9%. In particular, the AD and AB starters showed high tittatable acidity after 27 days of fermentation by oxidizing ethanol to acetic acid as the fermentation period passed after the 9-day induction. In contrast, a single AAB did not produce acid at 20 \({}^{\circ}\)C, whereas multiple AAB did. After 27 days at 20 \({}^{\circ}\)C, multiple AAB showed an average tittatable acidity of 4.01 \(\pm\) 0.54%, and the growth increased 8.25 times, compared to that on day 0 (Figure 1a,d). The AC and BD starters showed high tittatable acidity on day 27 after a 12-day induction period. In addition, multiple AAB failed to grow and produce acid at 40 \({}^{\circ}\)C (Figure 1c,f). Multiple starters were inoculated into a liquid medium with initial pH adjusted to 2.0-4.0 and fermented at 30 \({}^{\circ}\)C for 27 days to measure the tittatable acidity and growth of multiple AAB according to the initial pH (Figure 2). The initial acidity was increased by decreasing pH (acidity as pH decreases: pH 2.0, 5.24%; pH 3.0, 3.24%; pH 4.0, 0.35%) (Figure 2a-c). The six AAB starters, except the ABCD starter, produced acetic acid through ethanol oxidation after a 6-day induction period at pH 3.0, and the tittatable acidity rapidly  
Figure 1: Changes in tittatable acidity (**a–c**) and growth (**d–f**) under multiple starters according to fermentation temperature and period.