# Yeast Starter Culture Identification to Produce of Red Wines with Enhanced Antioxidant Content
## 3 Results
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**ITEM** & **TPC** & **TPC** & **TEAC** & **TEAC** \\  & **(\(\mu\)gGAE/mL)** & **\% Reduction** & **(\(\mu\)umoITE/mL)** & **\% Reduction** \\ \hline
6993 & 600.81 \(\pm\) 1.10 dc & \(-32\)\% & 4.49 \(\pm\) 0.06 cd & \(-21\)\% \\
**6920** & **701.70**\(\pm\) 0.60 b & \(-20\)\% & **4.56**\(\pm\) 0.16 cd & \(-19\)**\%** \\
8766 & 611.59 \(\pm\) 37.60 cd & \(-30\)\% & 4.38 \(\pm\) 0.02 cd & \(-22\)\% \\
14093 & 630.71 \(\pm\) 0.76 bedge & \(-28\)\% & 4.44 \(\pm\) 0.07 cd & \(-21\)\% \\
**9500** & **699.74**\(\pm\) 1.41 bc & \(-20\)\% & **4.62**\(\pm\) 0.02 bc & \(-18\)**\%** \\
9501 & 551.04 \(\pm\) 20.00 ef & \(-37\)\% & 4.22 \(\pm\) 0.14 d & \(-25\)\% \\
**9507** & **712.13**\(\pm\) 2.49 b & \(-19\)\% & **4.51**\(\pm\) 0.02 cd & \(-20\)**\%** \\
**9508** & **801.64**\(\pm\) 53.60 a & \(-9\)\% & **4.97**\(\pm\) 0.20 b & \(-12\)**\%** \\
9530 & 639.39 \(\pm\) 26.60 bcd & \(-27\)\% & 4.43 \(\pm\) 0.04 cd & \(-22\)\% \\ CM & 502.04 \(\pm\) 0.13 f & \(-43\)\% & 3.12 \(\pm\) 0.02 f & \(-44\)\% \\ Must & 876.57 \(\pm\) 5.15 a & / & 5.66 \(\pm\) 0.04 a & / \\ \hline \hline \end{tabular} The reported values are means (\(n=3\)) \(\pm\) standard deviation. Mean that do not share a letter are significantly different. The results of the four best-performing strains were reported in bold. Data were submitted to one-way analysis of variance (ANOVA), [PERSON]’s post hoc method was applied to establish differences between each yeast strain versus control. Different letters indicate statistically significant differences (\(p<0.05\)).  
\end{table} 
Table 3: Analysis of Total Phenolic Content (TPC) and Trolox Equivalent Antioxidant Capacity (TEAC) of wines obtained from the nine selected yeasts and the commercial strain (CM). molecules compared to the control. The total anthocyanin content detected in each of the produced wines is shown in Figure 1. Total anthocyanin content was significantly higher than the control for all samples, except for the wine fermented by the 8766 strain, while the sample fermented by the 9530 strain exhibited a significantly lower anthocyanin concentration. HPLC data were subjected to Principal Component Analysis (PCA) based on Pearson correlation (\(n-1\)) (Figure 2). The two principal components described the 66.33% of the total variance (36.98% and 29.35% for PC1 and PC2) of the phenolic acids data matrix: The analysis permitted the separation of yeast strains on the plane defined by two principal PCs. ITEM 9501, CM, and 9530, located to the left of PC2 result anti-correlated with the identified molecules, showing low concentrations. ITEM 9500 and ITEM 8766 cluster along the positive component of PC2 and show good correlation with trans-resveratrol, oenins, and quercetin. Along the positive component of PC1, ITEM 6993 is positively associated with trans-coutaric, caftaric, gallic acids and catechin. Finally, in the plane bounded by the positive components of the two PCs, we locate the cluster formed by ITEM 9507, 6920, 9508 and 9500 united by values closer to the mean value of all the molecules analyzed, showing profiles that are more balanced. Based on the processing of the obtained data, strains ITEM6920, ITEM9500, ITEM9507, and ITEM9508 fulfilled the fundamental parameters required, in that: the grafted alcoholic fermentations had a consistent progression and duration (<10 days). FT-IR analysis confirmed the attainment of the expected ethanol content, with sugars being completely consumed (residual < 2 g/L) in the produced wines. Notably, these four demonstrated the absence of undesirable metabolites, particularly showing very low production of acetic acid (volatile acidity < 0.2 g/L). The wines produced showcased a reduction in the concentration of total polyphenols (\(\leq\)20% TPC reduction) and a reduction in the antioxidant power (\(\leq\)20% TEAC reduction). As a result, these four strains emerged as promising candidate starters for subsequent pilot and industrial-scale experiments set to be carried out in the winery.