t seems to be an undisputed fact among experts that better quality wines are produced from old vines. There are also many winegrowers or wine producers who advertise with the words "old vine", "viñas viejas" or "vieilles vignes". We did some research and wanted to find out whether there is any truth to this or whether it is just a myth.
When is a vine considered old?
Firstly, we want to clarify when a vine is considered "old" and the average age that vines can reach.
There are no guidelines as to when a vine can be considered old, but the age of 30, sometimes even 35 years, has been rumoured.
A vine produces its highest yields after 5-10 years [1], after which the vine begins to age and the yield slowly decreases. Some vines have already reached the end of their life cycle at the age of 25 and are no longer economically viable from this age due to diminishing yields. However, this age cannot be applied to all grape varieties.
The oldest known vine that is still used for wine production is the Žametovka vine in Maribor, Slovenia [2]. It is said to have existed since the 17th century and is therefore between 300 and 400 years old. There is also a 350-year-old Versoaln vine in South Tyrol. There are other examples of old vines described in [2], so we will not list them all here.
Is there a connection between the age of the vine and the quality of the wine?
Young vines up to 3-5 years of age are not generally used to produce quality wines, as they are not yet fully developed and their foliage is still incomplete and full of holes. However, some winegrowers are of the opinion that it is precisely these young vines that are capable of producing grapes for wines of excellent quality [4].
There are different theories about the influence of the age of the vines on the quality of the wine:
According to [1], the advantage of old vines over young ones lies in the greater proportion of old wood and the larger root ball, which makes the plants more resistant to drought stress, as the old wood and larger root ball provide more reserves that the plants can draw on for a longer period of time and thus better withstand dry periods. However, this fact has more of an influence on yield than on quality (see above).
The sap flow can be impaired by a higher degree of lignification, which means that less liquid reaches the grapes and the concentration of the constituents increases as a result. However, if less juice reaches the grapes, the quantity of ingredients transported into the grapes via the juice is also lower. This argument should therefore be viewed critically.
Older vines have deeper roots and therefore have better access to deeper water reserves during dry periods. As there are different soil layers at these depths - we are talking about around 15 - 20 metres - than at shallower depths, the supply of minerals also differs. The different supply of minerals can certainly make a difference to the flavour and taste. Different soil layers also contain different strains of bacteria, whose metabolism can also have an influence on the flavour. Other authors, on the other hand, claim that this mineral content does not play a major role, but that the mineral content near the soil surface is decisive, as the plants develop finer roots there, which are better suited to absorbing the minerals.
As we can see, there are different explanations for the hypothesis of better wine from "old vines" and no unanimous opinion, let alone scientific findings.
What factors influence the quality of wine?
Let's take a look at the environmental factors that influence the quality of wine. The majority of factors can be categorised under the broad umbrella term "terroir".
Firstly, there is the climate, macroclimate and above all the mesoclimate, which can vary from vineyard to vineyard. The soil with its organic and mineral components as well as bacteria, which undoubtedly have a major influence on aroma and flavour, can also differ from plot to plot.
There is the topography, i.e. the surface shape of a landscape such as the height of the vineyard, the slope, the direction of the compass and the proximity to bodies of water.
The grape variety is a matter of course and should only be mentioned in this context.
he winegrower can significantly influence the wine quality through certain cultivation measures such as fertilisation, foliage management, grape pruning and the type of cultivation.
This is not the end of the story: cellar techniques such as the use of yeast bacteria, fermentation such as fermentation time, with or without mash, temperature control, storage of the wine, ageing vessels such as wood, steel or concrete tanks have a significant influence on the quality of the wine.
So we can see that with this enormous variety of possible influences on the quality of the wine and thus on its aroma and flavour, it is highly unlikely that a single parameter such as the age of the vine can be held responsible.
Findings from research
Geisenheim University has also dedicated itself to this topic and launched a project entitled "Old Vines". In this project, an attempt was made to exclude the above-mentioned terroir influences such as mesoclimate, differences in soil composition, etc. Vines of different ages (8 years) were analysed. Vines of different ages (8, 26 and 50 years) were planted and the analytical results from the berry constituents, wine constituents and sensory analysis were analysed to determine which vines - if any - showed differences in quality.
The trials were carried out over a period of several years. In all test years, a wine from all three ageing grape varieties was produced under the same conditions and analysed both analytically and sensory. In the first two years of the trials, the wines from the young vines differed from those of the other two age groups, as the vines were not yet fully developed. Thereafter, after the young vines had fully developed, no further analytical or sensory differences could be detected [3]. Based on these results, it was concluded that older vines do not produce wines of different quality compared to young vines. This statement contradicts conventional wisdom.
If you would like to read this again in the original, you will find the links and references to the relevant sources below.
References
[1] | Die Welt der Rebsorten, Martin M. Schwarz, 03.2003, Hoffmann und Campe, ISBN 3455303307 |
[2] | Wikipedia Artikle “Old vine”: https://en.wikipedia.org/wiki/Old_vine |
[3] | https://www.hs-geisenheim.de/praxis/wein-sensorik/rebalter/ |
[4] | Das Oxford Weinlexikon, Jancis Robinson, Hallweg Verlag 2003, 2. Auflage |
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