Résumé
Château Saint-Cosme is located in Gigondas in the southern Rhône valley. Its viticultural practices, organic and biodynamic, are adapted to the climatic constraints of the region, in particular the hydric deficit, the frost or strong bad weather. The work in the vineyard is designed to improve the biological activity of the plots, especially the soil, in order to obtain the best quality raw material. In the cellar, the adoption of a qualitative approach using the least amount of input enhances the terroir. The Château combines tradition and modernity without overly marking the wines with technology. The vinifications follow a philosophy of preservation of a typicity while using innovations if they allow to improve the wines produced. The experimentation this year will be based on the comparison between 4 LSA and a spontaneous fermentation. After a thorough bibliographic research, B2000, Be Thiol, Sodelight and Alchemy I were selected as modalities. The cold fermentation kinetics went smoothly, except for the indigenous yeasts that had difficulty finishing the last sugars. The aromatic profile of the B2000 and Sodelight modality was found to be very similar to that of the 5 batches following tasting by the Saint Cosme team. No impact of aroma production by yeast was statistically justified by the ANOVA, probably because of a too complex tasting form. Finally, SO2, which was found to be lacking during the previous vinification (NOP certification limit), was not exceeded by the 5 modalities. The B2000 is the most suitable for the criteria of the experiment. However, it will be necessary to pay attention to the total SO2 by carrying out new tests on the reduction of the use of sulphur dioxide.