terclim by ICS banner
IVES 9 IVES Conference Series 9 Influence of agrophotovoltaic on vine and must in a cool climate

Influence of agrophotovoltaic on vine and must in a cool climate

Abstract

The current energy crisis means that interest in agrophotovoltaics has increased significantly. The reason behind this is that the system aims to combine agricultural production with energy production. During the three-year period from 2020 to 2022, the effects of photovoltaic panels on the vine, the yield and the quality of the must were studied in Walenstadt in northern Switzerland, an area with a cool, humid climate. 65 Pinot noir vines were planted in the 160m2 study area. Because of the large edge effects, only 3 repetitions with 4 vines each could be created. A significantly lower leaf infestation by Plasmopara viticola was observed among the panels in each of the three years. However, in 2021 a significantly lower grape infestation was observed with an extremely high infestation pressure. In contrast, significantly higher powdery mildew leaf infestations were observed in 2020 and 2022, with infestations well below the economic threshold. During the three-year study period, the sugar content among the panels was significantly lower at around 0.9 to 1.8 Brix, and the total acidity was significantly higher between 1 and 1.3 g/l. These results indicate an approximate 1-week delay in ripening. Growth was optically stronger underneath the panels throughout the dry years 2020 and 2022, but only in the latter was it possible to measure a significantly higher pruning weight. The significantly lower value of the relative carbon isotope composition (Δ13C) in must sugars under the panels indicates greater water stress compared to the control, which can be attributed to reduced transpiration under the panels.
Conclusion: In the three years observed no significant negative impact of the photovoltaic panels could be determined, either on the yield or on the components of the must. The delay in ripening is usually a positive aspect, as is the reduced pressure from downy mildew. However, there is still a need for optimisation in construction so that unhindered mechanical cultivation is possible.

DOI:

Publication date: December 20, 2023

Issue: OENO Macrowine 2023

Type: Article

Authors

Peter Schumacher1

1 ZHAW Zurich University of Applied Sciences

Contact the author*

Keywords

Agrophotovoltaic, Plasmospara viticola, berry composition, water stress

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

Related articles…

OPTIMIZING THE IDENTIFICATION OF NEW THIOLS AT TRACE LEVEL IN AGED RED WINES USING NEW OAK WOOD FUNCTIONALISATION STRATEGY

During bottle aging, many thiol compounds are involved in the expression of bouquet of great aged red wines according to the quality of the closure.1,2 Identifying thiol compounds in red wines is a challenging task due several drawbacks including, the complexity of the matrix, the low concentration of these impact compounds and the amount of wine needed.3,4
This work aims to develop a new strategy based on the functionalisation of oak wood organic extracts with H₂S, to produce new thiols, in order to mimic what can happen in red wine during bottle aging. Following this approach and through sensory analysis experiments, we demonstrated that the vanilla-like aroma of fresh oak wood was transformed into intense “meaty” nuances similar to those found in old but non oxidized red wines.

SENSORY PROFILES AND EUROPEAN CONSUMER PREFERENCE RELATED TOAROMA AND PHENOLIC COMPOSITION OF WINES MADE FROM FUNGUSRESISTANT GRAPE VARIETIES (PIWI)

Planting grape varieties with several resistance loci towards powdery and downy mildew reduces the use of fungicides significantly. These fungus resistant or PIWI varieties (acronym of German Pilzwiderstandsfähig) contribute significantly to the 50% pesticide reduction goal, set by the European Green Deal for 2030. However, wine growers hesitate to plant PIWIs as they lack experience in vinification and are uncertain, how consumer accept and buy wines from these yet mostly unknown varieties. Grapes from four white and three red PIWI varieties were vinified in three vintages to obtain four diffe-rent white and red wine styles, respectively plus one rosé.

IMPACT OF MUST NITROGEN DEFICIENCY ON WHITE WINE COMPOSITION DEPENDING ON GRAPE VARIETY

Nitrogen (N) nutrition of the vineyard strongly influences the must and the wine compositions. Several chemical markers present in wine (i.e., proline, succinic acid, higher alcohols and phenolic compounds) have been proposed for the cultivar Chasselas, as indicators of N deficiency in the grape must at harvest [1]. Grape genetics potentially influences the impact of N deficiency on grape composition, as well as on the concentration of potential indicators in the wine. The goal of this study was to evaluate if the che- mical markers found in Chasselas wine can be extended for other white wines to indicate N deficiency in the grape must.

INVESTIGATION OF MALIC ACID METABOLIC PATHWAYS DURING ALCOHOLIC FERMENTATION USING GC-MS, LC-MS, AND NMR DERIVED 13C-LABELED DATA

Malic acid has a strong impact on wine pH and the contribution of fermenting yeasts to modulate its concentration has been intensively investigated in the past. Recent advances in yeast genetics have shed light on the unexpected property of some strains to produce large amounts of malic acid (“acidic strains”) while most of the wine starters consume it during the alcoholic fermentation. Being a key metabolite of the central carbohydrate metabolism, malic acid participates to TCA and glyoxylate cycles as well as neoglucogenesis. Although present at important concentrations in grape juice, the metabolic fate of malic acid has been poorly investigated.

Managing changes in taste: lessons from champagne in britain 1800-1914

This paper focuses on how taste in wine (and other foods) changes and the implications of this process
for producers and merchants.
It draws primarily on the changing taste of and taste for champagne in Britain in the 19th century. Between 1850 and 1880 champagne went from a dosage level of around 20% (20 grams sugar / litre) to 0%. Champagne became the ‘dinner wine of the elite – drunk with roast meat and savoury dishes.
Contemporaries accepted that while most people could distinguish the taste of good champagne from that of bad, very few could distinguish very good from good.