Macrowine 2021
IVES 9 IVES Conference Series 9 Maturation under different SO2 environments: the impact on amino acid and volatile profile for two white wines

Maturation under different SO2 environments: the impact on amino acid and volatile profile for two white wines

Abstract

EU countries are in the top 16 of the world’s wine producers. To respond to a public health concern, caused by SO2 excessive exposure, EU has required a warning in the products indicating that sulphites are present if concentrations are higher than 10mg/L and its reduction or replacement whenever possible. This additive is used as a preservative agent in the winemaking process, due to its antioxidative and antimicrobial properties[3]. Wine aroma depends on many factors, being grape variety and winemaking process that most contributes to volatile organic composition (VOC) found in wines where amino acid composition, due to their biosynthetic products play an important role. Also, during wine ageing VOCs can change depending on many factors such as temperature, pH or oxidation process[4]. In this work, the impact of different doses of SO2 (added after alcoholic fermentation) was evaluated on wine VOCs over time and amino acids content after 3 months over lees.

HS-SPME-GC/MS was used to identify and semi-quantify VOCs, and HPLC-DAD was used for amino acids quantification. Two white wines were studied: one varietal (Antão Vaz; AV) and one blend (BL) of Portuguese varieties. After being kept for 3 months over lees, wines were bottled and VOCs and amino acids were analysed after 3 and 6 months.

A total of 83 compounds were tentatively identified,70 compounds in monovarietal wine and 73 in the blend wine. The chemical functional groups observed were esters, alcohols, carboxylic acids, aldehydes and 12 miscellaneous compounds. When a Principal Component Analysis (PCA) was performed on VOCs semi-quantification of each wine it is observed that PCA plots present different trends throughout the factors under study. In Antão Vaz was attain lower samples distinction for different SO2 doses on sample with 3 and 12 months. However, for the evolution time of 6 months, samples were well separated. In this case, both factors seem to influence the distribution of samples with a similar weight. For the blend wine, a worse distribution of the samples was observed for evolution time of 3 and 6 months. This indicates that they might be more sensitive to SO2 doses and evolution time when compared with Antão Vaz wines. Regarding amino acids profile it was observed that maturation on lees lead to an increasing concentration of AA. However, Antão Vaz was more influenced by the SO2 doses applied.

DOI:

Publication date: September 13, 2021

Issue: Macrowine 2021

Type: Article

Citation

Related articles…

Plastic debris at vines: carriers of pollutants in the environment?

Modern agriculture employs large amounts of plastics, such as mulching and greenhouse films, thermal covers, plant protection tubes and tying tape. The latter two types are very common in viticulture. Guard tubes are employed to protect young vines from mechanic and atmospheric damage, whilst polymeric tying tape has replaced natural-origin materials to hold the canopy of vines. Both materials are made on synthetic polymers, which include a range of additives to improve their environmental stability remaining in the environment of vineyards for years. During this time, they are exposed to the range of pesticides (fungicides, insecticides and in a lesser extend herbicides) applied to vines.

Breeding grapevines for disease and low temperature tolerance: the U.S. perspective

Most grape scion cultivars grown around the world are derived from a single species, Vitis vinifera. Yet, the proportion of interspecific hybrids is increasing for a variety of reasons, including resistance to abiotic stresses such as low temperatures; societal, economic and environmental pressures to reduce pesticide usage; and to add a greater range of flavors to new table grape cultivars.

Méthode et outils de valorisation des terroirs en cave coopérative

Depuis le début des années 90, les vignerons des Caves Coopératives de l’Appellation “Côtes du Rhône” se sont penchés, au sein des structures de réflexion du Syndicat Général, sur deux axes de réflexion:
– Détermination des critères de sélection et de rémunération différenciée des apports de vendange;
– Organisation des sélections de vendanges sur la base des terroirs afin d’augmenter quantitativement le potentiel de sélection au sein de l’unité de production.

Characterization of the adaptive mechanisms of grapevine rootstocks to iron deficiency induced by lime stress

Iron (Fe) deficiency is one of the important nutritional disorders for grapevine growing in alkaline and calcareous soils. Although Fe is an abundant element in soil, several factors limiting its availability, particularly the high levels of calcium carbonate or bicarbonate in soil, leading to a remarkable reduction in grapevine growth and productivity. The use of Fe chlorosis-tolerant rootstocks seems to be a cost-effective and efficient way to maintain Fe balance. Morphological and physiological changes occur in plants to cope with low Fe availability, including enhancement of ferric chelate reductase activity and altering root system by increasing lateral roots and root hairs.

Effects of stress memory on grapevine resilience in response to recurrent drought and recovery events 

Plants have evolved different strategies to cope with environmental stresses and, although still debated, it was observed that they can remember past stress occurrence.
Anatomical and physiological adjustments have been observed in different grapevine cultivars after repeated drought exposure, however epigenetic, transcriptional and biochemical changes associated with drought-primed ecological memory have been poorly studied.
This work was conceived to test whether exposure to recurring events of mild drought could prime vines to endure severe drought stress. Particularly, we investigated whether the expected improved stress tolerance of Vitis vinifera cv Nebbiolo plants subjected over years to moderate and long-lasting water stress events (WS-primed) depended on molecular memory phenomena or on resetting of stress-induced signals.