## 4 Conclusions  
A commercially available additive rich in organic nitrogen compounds was tested in four white wine fermentations, using both spontaneous and flocculent yeast-driven  
Figure 5: Normalized and scaled data of the wine attributes obtained by organoleptic analysis. WY: wine obtained by spontaneous fermentation with wild yeasts; WY + Act: wine obtained by spontaneous fermentation with an activator; AGGLO: wine obtained by fermentation with commercial ADY Levulia® AGGLO; AGGLO + Act: fermentation with commercial ADY Levulia® AGGLO with an activator. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Attributes** & **WY** & **WY + Act** & **AGGLO** & **AGGLO + Act** & **HG** & \(p\)**-Value** \\ \hline Sight & \(10\pm 2\)\({}^{\text{a}}\) & \(11\pm 2\)\({}^{\text{a}}\) & \(11\pm 1\)\({}^{\text{a}}\) & \(12\pm 1\)\({}^{\text{a}}\) & \(1\) & \(0.506\) \\ Smell & \(24\pm 3\)\({}^{\text{a}}\) & \(24\pm 2\)\({}^{\text{a}}\) & \(23\pm 3\)\({}^{\text{a}}\) & \(23\pm 4\)\({}^{\text{a}}\) & \(1\) & \(0.740\) \\ Taste & \(34\pm 5\)\({}^{\text{a}}\) & \(36\pm 4\)\({}^{\text{a}}\) & \(33\pm 5\)\({}^{\text{a}}\) & \(33\pm 5\)\({}^{\text{a}}\) & \(1\) & \(0.544\) \\ Overall quality & \(9\pm 1\)\({}^{\text{a}}\) & \(9\pm 1\)\({}^{\text{a}}\) & \(9\pm 1\)\({}^{\text{a}}\) & \(1\) & \(0.401\) \\ Total score & \(78\pm 8\)\({}^{\text{a}}\) & \(80\pm 8\)\({}^{\text{a}}\) & \(76\pm 8\)\({}^{\text{a}}\) & \(77\pm 10\)\({}^{\text{a}}\) & \(1\) & \(0.708\) \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Evaluation of organoleptic attributes. Mean score, standard deviation, and homogeneous groups at a confidence level of 95% (\(p\leq 0.05\)). Letters (*) in the same row indicate significant differences between wines. Abbreviations used for wines obtained by fermentation with WY: wild yeast; WY + Act: the same with the addition of an activator; AGGLO: Levulia® AGGLO yeast; AGGLO + Act: the same with the addition of an activator. processes. As a control, two of these fermentations were conducted without additive supplementation. No significant differences in standard enological variables were obtained. The supplement added increased the fermentation rate of the flocculent yeast and reduced the volume of lee formation. Wines obtained by spontaneous fermentation with the tested additive showed a significant reduction in fruits, green fruit, green, creamy, citrus, chemistry, honey, and floral odorant series values compared to those without the additive. In contrast, wines fermented with flocculent yeast and supplemented with the additive showed a significant increase in all the aroma series, except the waxy series, compared to their counterparts. Volatile compounds analysis suggests a strong interplay between the predominant fermentative yeast behavior and the supplementation of must with the tested additive in shaping the wine's aroma profile. Depending on the dominant yeast during fermentation, the presence of the additive affects the volatile compounds and, consequently, the odorant series differently. Although volatile differences were observed, the lack of significant sensory differences suggests that the impact on aroma perception may be limited. Further organoleptic studies are required to confirm and extrapolate these results. This study enhances the understanding of flocculent yeast metabolism and its fermentation process, highlighting its distinct behavior in nitrogen-rich environments compared to wild yeasts. The combination of natural yeast extracts, rich in organic nitrogen compounds, with selected yeast strains improves fermentation efficiency, increasing yield and aroma production--an important advancement for the winemaking industry. Future work should analyze additional nutrient components beyond ONC levels to better understand the effects of ONC addition and yeast inoculation on fermentation.