The Effects of Flocculant Yeast or Spontaneous Fermentation Strategies Supplemented with an Organic Nitrogen-Rich Additive on the Volatilome and Organoleptic Profile of Wines from a Neutral Grape Variety
Muñoz-Castells, Raquel | Sánchez-Suárez, Fernando | Moreno Vigara, Juan José | Álvarez-Gil, José Manuel | Moreno-García, Jaime
The effects of spontaneous fermentation and the inoculation of grape must with a flocculant yeast starter culture, together with the supplementation of must with a commercial organic nitrogen compound (ONC), were analyzed. The microbiome during fermentation was tracked, and volatile compounds in the resulting wines were identified and quantified using gas chromatography and mass spectrometry (GC-MS). Volatile compound concentrations were then subjected to statistical analysis. No significant differences in pH, titratable and volatile acidity, and ethanol and lactic acid were observed among the four wines analyzed. However, the musts supplemented with the ONC slightly increased the fermentation rate of the flocculant yeast, and, also, this additive reduced the volume of lees in the spontaneous fermentation and flocculant yeast by 1.2% and 0.6%, respectively. The concentrations of 11 major and 28 minor volatiles were significantly influenced (p-value ≤ 0.05) by the inoculation strategy, while 8 major and 28 minor volatiles were affected by ONC supplementation. This supplementation significantly decreased the Odor Activity Values and, consequently, the values of the odorant series established in wines from spontaneous fermentation. On the contrary, those from flocculant yeast showed a significant increase in all the odorant series except for the waxy series, leading to a more balanced aroma profile. Additionally, lower scores were recorded for the green, creamy, citrus, chemical, and honey series compared to wines from spontaneous fermentation. Overall, the commercial ONC extract contributed to a content increase in volatiles that provided desirable aromatic notes to the wines made with flocculant yeast, although the organoleptic evaluation showed no significant statistical differences in the attributes evaluated at the 95% confidence level.
Показать больше [+] Меньше [-]