Climate change impact study based on grapevine phenology modelling

The oenological potential of grapes at harvest depends on a combination of the major components of Terroir: the climate, the soil, the plant material, the training system and the crop management.

Sessile oak and pedunculate oak have shown several differences of interest for enological purposes. Tannic and aromatic composition among sessile oak or pedonculate oak has been well studied. Sessile oak is generally more aromatic than pedunculated, while the later is more tannic. This scientific point of view is rarely applied to classify oak in cooperages. Most coopers use the type of grain to distinguish wide and thin grain.

The aromatic quality of wines after a long aging period in bottle is one of key points for oenologists. The objective of this work is to determine the main representative aromatic compounds found in long aged wines from D.O.Ca. Rioja. This study was made by 32 wines from 1971 to 2010 vintages. Sotolon, acetaldehyde, phenylacetaldehyde, 1,1,6-trimethyl-1,2-dihydronaptalene (TDN), β-damascenone, Y-decalactone and Y-dodecalactone were determined as the most important oxidation markers by GC-MS analysis. Moreover, sensory analysis using triangular tests were performed from wines with and without the addition of the mentioned compounds. Four different concentrations of each odorant were added, as individual compounds and as mixtures. The additions were ranged from values close to the reference odour thresholds up to high level concentrations. The most identified aroma was sotolon, which is commonly associated to curry and coffee liqueur aromatic notes. Other oxidative compounds were easily detected by panellists, such as Y-decalactone (peach compote), Y-dodecalactone (ripe fruit). The mixtures of the odorants were most easily detected than the individual compounds. It should be noted that acetaldehyde and phenylacetaldehyde were rarely perceived and distinguished.

Red wines can undergo many undesirable changes during the winemaking process and storage, particularly oxidative degradation due to numerous atmospheric oxygen intakes. This spoilage can impact organoleptic properties and color stabilization but this impact depends on the wine composition. Phenolic compounds constitute primary targets to oxidation reactions

Endogenic diseases often arise from pathogens that exist within the plant tissue, including fungi, bacteria, and viruses, which can remain latent and then emerge under stress conditions or favorable environmental conditions, causing symptoms that weaken vines or can lead to plant death.