The availability of older wine vintages in a wine monopoly

Sweden has a single government-owned (but not controlled) alcohol retail monopoly, called Systembolaget (although Swedes often refer to it as Systemet = The System). Many non-Swedes see this as an affront to free trade, and that it obviously must be economically inefficient (e.g. “high taxes are also an issue in the Nordics, where sales are stifled by everything having to be sold through monopolies”).

I have written about this situation quite a number of times, pointing out that the situation is not really the way it is painted by outsiders (ie. sales are not stifled). For example:

• Which countries are dominated by only a few alcohol suppliers?
• Why are there wine monopolies in Scandinavia?
• The WHO is making a mistake about state-owned alcohol retailers

I have also written about the availability of wine under these circumstances, as many people seem to think that it must be restricted in some way, which it is not:

• Wine monopolies, and the availability of wine
• The availability of wines in government-owned retail monopolies
• The availability of older wine vintages in Sweden?

It is the topic of this latter post, about older vintages, that is of interest here. In that post, from 2024, I listed all of the available Australian wines at least 5 years since vintage, available in Systembolaget. There were 24 of them, vintage dated 2013–2018. This seems to me is not too bad a selection, from a single source country, and all of the wines should still be quite drinkable. However, people used to specialist wine shops might find that this selection is nothing to write home about, especially in countries like the USA, where specialty retail is expected.

Today I am going to look at all of the available wines vintage–dated prior to 2000 (ie. last century), irrespective of their country of origin.

The table below shows the results of my searching in the Systembolaget database. These are all table wines, not fortified wines (which can be much older, as their higher alcohol content preserves them). I have shown the Swedish (SEK) price for each wine. Note that US$ 1 ≈ 10 SEK, which makes the conversion easy.

So, there are 7 red wines and 6 whites. This may not impress connoisseurs; but for the Swedish national retail chain, where almost all of the alcohol sold is budget stuff for everyday drinking (the classic “wines for the table not the cellar”), it is as good as I would expect.

All of these wines should still be quite drinkable.

For example, the four Moulin Touchais wines come from a winery that specializes in a semi-sweet wine of great age; so many other old vintages have been available as well (see: Tasting the magical sweet wines of Moulin Touchais through the ages).

Similarly, the current release of the Xavier Vignon wine was not bottled until 2022, and it is widely available elsewhere (Wine-Searcher).

Also, although the company no longer exists, Richmond Grove long specialized in limited releases of its Watervale Riesling (e.g. in 2012 Chris Shanahan noted that the winery offered Watervale Rieslings from 1996 to 2011).

The Luis Pato wine was tasted in 2023 / 2024 by Wine Anorak, and given a score of 95/100.

A perusal of the Wine-Searcher database shows that the Giacomo Borgogno wine is widely available elsewhere. All of the other wines are also still available elsewhere (e.g. Bodegas Campillo, Fontanafredda, Jean Leon, Mastroberardino, Vajo dei Masi).

These wines are rarely actually in any of the Systembolaget retail stores, but are still in the importer / distributor warehouse. They can be ordered through the Systembolaget online order system, and arrive a few days later at my local store, where I collect (and pay for) them. This system works quite well.

Grape harvest dates and year-to-year climate variability (global climate change)

What we now call “climate change” used to be called “global warming”. The experts introduced the change in name in order to emphasize that there are actually two things that we need to be aware of:

1. the atmospheric temperature is increasing at an unprecedented rate
2. the weather is getting increasingly variable from year to year.

Both of these things are happening simultaneously.

Much of the evidence for both of these phenomena actually comes from agriculture, because we have good written records about harvest dates of various crops, often over centuries. These records show both of the patterns: harvest dates getting earlier and earlier on average, but also with erratic harvest dates from year to year.

I have written before about Grape harvest dates and the evidence for global warming. In that post I discussed several datasets from around the world, which all show the same patterns. In particular, the grape harvest dates for Burgundy are valuable, because of the 700 years over which they have been collected, from 1350 CE. I noted: “there has been a dramatic change in harvest date in recent years, with the earlier and earlier harvests since 1984 being attributed to global warming.”

The other weather pattern has also been emphasized in the wine industry recently (The dirt on wine):

“These days, you can’t say hot, cool, wet or dry vintage any longer. Weather has become totally unpredictable, with extremes even within one growing season,” began Diego Tomasi, director of the Centro di Ricerca per la Viticoltura e Enologia di Conegliano (CRA-VIT) in Italy. To emphasise his point, he projected onto a screen several graphs; one showing the increased variability of harvest dates in Burgundy in the past 15 years compared to the previous two centuries.

So, the obvious thing for me to do here is re-visit the Burgundy data, to show you the big picture.

I have used exactly the same dataset as in my previous post, containing a complete record of the official start of the Burgundy grape harvest for every year from 1370 to 2018 CE, inclusive. Last time, I calculated a running average of 9-year blocks of harvest dates, but this time I calculated the standard deviation of the harvest dates, instead. This calculation describes how variable the harvest dates were, across each 9-year period — a larger standard deviation indicates more variation from year to year (see my post on Statistical variance and global warming).

I have graphed the data above. Each dot represents one 9-year period. The horizontal line is simply the median value — half of the standard deviations are below the line and half are above it. The dashed lines show the inter-quartile range — half of the values are between the two dashed lines.

For our purposes here, I have highlighted the final 32 values — the final 16 are shown in red (since 2000) and the 16 before that in green. Note that red values are almost all above the upper dashed line (ie. in the top 25% of the variation) while the green ones are all below the lower dashed lines (ie. in the bottom 25% of the variation). This means that the recent harvest dates (this century) have been much more variable from year to year than were the ones immediately before that (the end of last century).

This emphasizes the quote above from Diego Tomasi — the Burgundy grape harvests are now much more variable than they have been within living memory.

However, as I noted in my previous post on the Burgundy harvests, the graph also illustrates that there have been recordings of previous large variations in the weather; indeed, on occasion even more extreme than we are observing now. In that sense, the current change in the weather is not necessarily unheard of, although it is definitely unusual.

This is what the climate-change skeptics are on about, and they are right when they point out that rapid changes in long-term weather have occurred before in our recorded history. This does not mean that the effects of the climate change will be any less, or that we do not need to respond to them. Our recent agricultural practices will have to change, irrespective of whether the current weather patterns have occurred before or not.

This point is emphasized by a recent study of soil moisture over the past 1,200 years (see Climate change: US megadrought ‘already under way’). The recent 20 years of relatively dry conditions is the fourth such period found by the study, so in that sense this is not unexpected (the previous megadrought ran from 1575–1603 CE). However, the authors also note that, while the current drought may be a natural event, it is being made much worse by climate change. That is, the effects of the natural event are being exacerbated.

What has happened to the 1983 Port vintage?

One of the most comprehensive sites about vintage port is VintagePort.se. This site was established in 2011, by three port enthusiasts from southern Sweden. It contains details about every port brand name, and its history (with a few rare exceptions). It also contains tasting notes about nearly every vintage wine produced under those brand names, often tasted more than once — this is well over a thousand tasting notes.

Many of these ports were tasted at meetings of The Danish Port Wine Club (in Copenhagen) or The Wine Society 18% (in Malmö). Among these, there have been a few Great Tastings, during which at least 20 port brands were tasted from a particular vintage. Earlier this year it was the turn of the 1983 vintage.

The 1983 vintage was highly rated in the mid 1980s, and 36 of the houses / brands released a vintage port (ie. almost all producers declared the vintage). A survey of the vintage scores from various commentators reveals this:

Rating out of 100 Tom Stevenson Wine Advocate Wine Spectator Cellar Notes Into Wine MacArthur Beverages Vinous Rating out of 10 Berry Bros & Rudd Oz Clarke Vintages (LCBO) Wine Society Passionate About Port Rating out of 5 Michael Broadbent Decanter For the Love of Port

1983 vintage 95 92 92 91 91 91 90 8 8 8 7 7 4 4 3

Best recent vintage 95 97 99 97 96 99 97 10 10 10 10 10 5 5 5

So, almost all of the commentators rated the vintage as 90+, but did not rate it as among the very best of the recent Port vintages. The VintagePort.se site notes that they also previously rated the 1983 vintage as Outstanding (a score of 18 / 20 = 95).

However, earlier this year, at their Great Tasting, the three port lovers re-tasted 31 of the 36 vintage wines from 1983. They were rather disappointed: "Many wines were defective with volatile acidity, and many wines were not what we had expected ... We have now changed this vintage to the rating Very Good" (score 15 / 20 = 88). This is quite a come down.

It is now 30 years since the 1983 ports were put in their bottles. This is not usually considered to be an especially long time in the life of a vintage port, although most of this vintage has probably been consumed by now. So, what has happened to these wines? It seems unlikely that bottle variation is responsible for the poor results. Maybe the corks in use at the time were not up to he job? Or, maybe the grapes just weren't as good as people thought at the time.

The three port enthusiasts were in general agreement with each other about the scores of the 31 individual wines (although Sten and Stefan agreed more often than Jörgen), so that their group ratings were consistent.

However, it might be better if we base our overall assessment of the wines on the average score from all 16 of the participants in the Great Tasting. They rated 2 of the ports as Excellent (17 points / 20), 4 as Very fine (16 points), 17 as Very good (score 15), 4 as Good (score 14), 1 as Average (score 13), and 3 as Below average. The two best ports were from Quarles Harris and Gould Campbell, while the three worst were from Real Vinicola, Dow's and Kopke.

You can check out the full results on their site. Overall, this is quite an impressive source of information for port aficionados.

Why lionize winemakers but not viticulturists?

It is widely noted that viticulturists can have as much influence on the quality of the final wine as do winemakers, and yet it is still the winemakers whose names are most widely known, because they are the ones who most commonly appear in the wine press. So, the people in the winery get the media attention more than those in the vineyard, even though the location of that vineyard is acknowledged to be of prime importance.

To counteract this trend, in this post I discuss one example, from Australia, where the viticulturist often gets almost as much press as the winemaker.

Wynns Coonawarra Estate is by far the biggest winery in the Coonawarra region of Australia, a region that has an international reputation for the quality of its cabernet sauvignon wines (although the shiraz wines are not too shabby, either). Wynns consistently project three people as being their "team", as listed in the first photo below. [Note: Ben Harris, the Vineyard Manager, tends to go missing from most of the press; see the photo at the bottom of the post.]

What is more important for our purposes here, the media actively go along with Wynns' attitude. I have listed a few press reports at the end of this post, as a small sample of what the wine media have to say. The two people titled "winemaker" do get more press than the viticulturist, although much of their personal press does tend to emphasize them as females in a male-dominated profession. Indeed, Sue Hodder and Sarah Pidgeon were jointly named the 'Winemaker of the Year' at the 2016 Australian Society of Viticulture and Oenology (ASVO) Awards for Excellence.

However, back in 2010, when Sue Hodder was named Australian Gourmet Traveller WINE’s 'Winemaker of the Year', a new award was introduced for Allen Jenkins: 'Viticulturist of the Year'. Part of the reason for acknowledging the importance of the viticulturist at Wynns has been his role in rejuvenating the vineyards over the past 15 years, and the clear effect that this has had on the quality of the wines.

L to R:  Sarah Pidgeon (Winemaker)
Sue Hodder (Chief Winemaker)
Allen Jenkins (Regional Vineyard Manager)

The rejuvenation program

Sue Hodder joined Wynns just prior to the 1993 vintage; and she was then appointed Chief Winemaker in 1998, at which point Sarah Pidgeon became Winemaker. Allen Jenkins arrived as the viticulturist in 2001-2, at least partly because Hodder and Pidgeon had realized that the vineyards needed extensive treatment, if the wines were to be improved.

For example, during the 1990s it was noted that the vines were building up too much dead wood, as a result of 20 years of (minimal) mechanical pruning. Indeed, the vines were reported to be so low yielding that they were hard to pick. The rejuvenation started in 2000, and was accelerated in 2002. It was expected to take eight years to complete; and the change in the wines was reported widely in the media starting from 2010.

The process involved large-scale vine regeneration by heavy chainsaw pruning of very old vines (shiraz up to 120 years old, cabernet sauvignon up to 60 years old), removing the dense clusters of dead wood, and thus bringing the vines back to a new physiological balance. Tired or diseased vines were grubbed out, along with the removal of lesser varieties. These were all replaced by new clones and rootstocks of cabernet and shiraz, for which the winery developed a heritage nursery, based on cuttings from time-proven vines. There was re-trellising, along with changed canopy management and new pruning techniques. The vineyards were also converted from sprinkler to drip irrigation.

Along with all of this, the winery was also modified to focus more on small-batch vinification, from 2008 onwards. This allows the grapes to be picked at perfect physiological ripeness, as even a large vineyard block can now be processed in many small batches instead of a few large ones. This takes advantage of the increased grape quality in the vineyard. The oak maturation of the wines has also been re-visited, resulting in a lighter handling, which now produces softer, more elegant wines. Indeed, the latter approach is a return to the style from the 1960s, rather than the heavier style favored in the 1980s and 1990s.

The flagship Wynns wines are the John Riddoch Cabernet Sauvignon and the Michael Shiraz, which are made only in years when grapes of very high quality are available. Production was stopped on both of these wines during the 2000-2002 part of the rejuvenation period. So, to see the effects of the rejuvenation on the quality of the Wynns wines, we need to look at a different product from the winery.

Black Label Cabernet Sauvignon

Within the Wynns range, the Black Label Cabernet Sauvignon holds a special place, even though it is marketed as the "basic" wine from the winery, with an average annual production of roughly 40,000 cases. The wine is currently blended from about 20 different small parcels of grapes, out of up to 80 that are contenders each year. The vines were planted mainly in the 1960s, 70s and 80s.

The flagship John Riddoch cabernet is always denser, more powerful and oaky than the cheaper Black Label, but the latter is always better value for money, selling for less than one third of the top wine's price (and often being aggressively discounted by retailers). Indeed, it has been repeatedly shown that the Black Label can age for decades, making it "possibly the most important cellaring wine in Australia", and forming "the backbone of many Australian cellars for over 50 years". This makes it "one of the most important wines in Australia’s wine history". Myself, I think that it is the best value-for-money cabernet wine that Australia produces.

There have been a number of retrospective tastings of this wine organized by Wynns, which go all the way back to the first vintage, in 1954. For example, there was an important vertical tasting covering the 50 years from 1954- 2004, which Hodder has described as the catalyst for the winemakers changing the style away from the heavier style of the 1990s. There was also a 60-year vertical tasting earlier this year.

However, the published reports from these tastings are somewhat sporadic. So, for an evaluation of the effects of the vineyard rejuvenation it will be simpler to cover a shorter period. The graph above shows the weighted average scores from the Wine-Searcher database, covering the vintages from 1990 (ten years before the rejuvenation started) to 2014, inclusive.

Note that for almost every year since 2004 the wine has been scored 91 or higher, whereas before that 91 was the rare top score. There is no doubt that the wine is in the best form it’s been in for years. And the viticultural team can take most of the credit.

Buy yourself a bottle. Put it away for ten years. Then drink it. You will see what I mean about value for money.

Bibliography

Who says New World wines don't develop? — Michael Apstein

Gourmet Traveller | Viticulturist of the year — Susanne Bell

Who dares Wynns — James Halliday

Wynns Coonawarra: a revolution many years in the making — James Halliday

Wynns wine legend turns 60 — Huon Hooke

A 17-year winemaking partnership — Cathy Howard

Interview with Sue Hodder —Jeannie Cho Lee

Wynns unleashes Coonawarra’s diversity — Chris Shanahan

Wynns Coonawarra — great winemaking but the marketing sucks — Chris Shanahan

How Sue Hodder’s history lesson improved Wynns’ Coonawarra reds — Chris Shanahan

Profile: Sue Hodder — Tyson Stelzer

Vintage charts, and the variation within a wine-growing region

I noted in a previous blog post that not everyone is enamored of vintage charts (Modern wine vintage charts: pro or con?). Such charts provide a quality score for each wine vintage in some specified wine-making region.

One of the objections to these charts is that the ratings over simplify — there is quality variation between vineyards even within local areas, and this is not taken into account. That is, not all wine producers will produce high-quality wine in allegedly good vintages; and not all wine producers will produce poor-quality wine in allegedly bad vintages.

I thought that it might be interesting to illustrate this point in practice.

I will do this using some data for the wines of Bordeaux, taken from Michel Dovaz' book: Encyclopedia of the Great Wines of Bordeaux (1981; Julliard).

For each classified wine-producing chateau, Dovaz provides a wine quality score for each vintage from 1970-1980 (plus some others). The scores indicate the quality of each vintage relative to the other vintages from the same producer, with the best one scaled as a score of 10. This means that the relative quality of each vintage can be directly compared between producers, without any concern about whether some producers are better than others — all producers have at least one vintage with a score of 10. [Technically, the data have been standardized to the same maximum value.]

We can look at these data for each of the different areas within the Bordeaux region, to see how much local variation there is in success for each vintage. Do all of the producers have success, or lack of success, in the same years? If so, then a vintage chart would be a very convenient way to tell us which were the successful years.

The first graph covers the red wines of the commune of Margaux, north of the city of Bordeaux. Each colored line represents the quality scores of a single chateau, with the solid line being the average of the scores in each year.

This graph alone represents the general point rather well. The chateaux do follow a single main pattern through time, but there is great variation around the average quality score. In particular, the chateaux do not all follow the same rank order of vintage quality. For example, 1970 was a better vintage than 1971 for most of the chateaux, but for one of them it was the other way around. Alternatively, 1976 was a better vintage than 1977 for all of the chateaux, although it was much better for many of them but only a little bit better for others.

The next graph covers the red wines of the commune of St Julien, which is the next one north of Margaux.

There are fewer chateaux represented here, but there is even more variation among these chateaux than there was for the Margaux area. Note, however, that there was very little variation in the 1975 vintage compared to the others.

The next graph covers the red wines of the commune of Pauillac, further north.

It is very similar to the previous graphs, being somewhat intermediate between the two of them.

There are too few classified chateaux in Saint-Estèphe to plot a worthwhile graph. So, we now move on to the area south of Bordeaux; and the next graph covers the red wines of the Graves region. There are too few Graves white wines to plot a worthwhile graph.

There are also few chateaux represented here. Note that for the first three vintages there is actually not much variation among the chateaux, but this changes for the rest of the decade, especially 1974.

The next graph covers the red wines of Saint Émilion, which is on the Right Bank of the Bordeaux region, rather than the Left. The adjacent area of Pomerol has data for only one chateau, and so it is included here, as well.

Clearly, the patterns of within-vintage variation are much the same for the Right Bank as for the Left. That is, not all of the chateaux follow the average pattern of variation, but most do, even though there is considerable variation among them.

Next, we can move on to Sauternes, the most famous white-wine region of Bordeaux, which makes very sweet wines.

This is the most expressive graph of all, regarding within-vintage variation. The making of high-quality sweet wines requires that the grapes be infected with Noble Rot (a fungus), and this process relies on very specific weather patterns. There were a number of years in the 1970s when the wine was deemed by a number of chateaux to be not worth releasing (scored 0 in the graph). Only in 1970 and 1975 did most of the chateaux produce high-quality wines.

Clearly, a vintage chart for Sauternes is not necessarily a reliable indicator of vintage quality. On the other hand, for the red wines shown in all of the previous graphs, such a chart would be useful in general. It would not, however, be a substitute for more detailed knowledge about each chateau.

Finally, lest we think that the results above are unique to the scoring system of Michel Dovaz, or are unique to the particular decade concerned, we could look at an independent source of data. The final graph shows the vintage quality scores from the Wine Spectator magazine, for the four "first growths" of the Médoc, covering the subsequent 33 years.

Even for these restricted chateaux, the within-vintage variation is large — the 1992 vintage was particularly variable. Note, however, that in this case the data have not been standardized, so that the within-year variation includes intrinsic variation in quality between the chateaux themselves (which may be small!).

Three centuries of Rheingau vintages — Schloss Johannisberg

The central German vineyard region of the Rheingau has a long history of active interest in vintage quality, as I have already discussed in the blog post The grand-daddy of all vintage charts. Individual vineyards within this region also have long records regarding their vintages, notably the three centuries of recording for Schloss Johannisberg. Finding this information online is not easy, and so I will be covering it in this blog post.

This post follows my previous ones on individual producers, including century-long records from Piemonte, in northern Italy: for Fontanafredda; and Marchesi di Barolo.

Schloss Johannisberg is formally known as Fürst von Metternich-Winneburg'sche Domäne Schloss Johannisberg. You can read all about the estate and winery at the Johannisberg web site (in both English and German).

The vintage data discussed here are taken from this book:

Josef Staab, Hans Reinhard Seeliger, Wolfgang Schleicher (2001) Schloss Johannisberg: Nine Centuries of Wine and Culture on the Rhine. Woschek-Verlag, Mainz.

It is written in both German and English [German title: Schloss Johannisberg: Neun Jahrhunderte Weinkultur am Rhein]. The data (pp. 119-128) cover the vintages from 1700 to 2000 inclusive, and were compiled by Dr. h.c. Josef Staab.

For almost every vintage, the data consist of wine quantity, in hectoliters, and a brief verbal description of quality. Unfortunately, the verbal descriptions vary greatly across the three centuries, and so they are not directly comparable. I have therefore standardized them into a semi-quantitative score as follows:

Score 0:  Acetic, frost [vintage entirely lost]
Score 1:  Not drinkable, very poor, very sour, extremely poor
Score 2:  Lesser wine, lesser year, poor, low quality and poor, unenjoyable, drinkable, sour
Score 3:  Mediocre, average, lesser to average, lesser to mediocre, modest
Score 4:  Good, good wine, good to very good, quite good, average to good, good average wine
Score 5:  Very good, extra good, particularly good, especially good, very good top wine, excellent
Score 6:  Top wine, trophy wine, first rate top wine, excellent top wine

Here is a summary of the harvest-quality data presented as a frequency histogram of increasing quality. For random data his would follow what is known as a binomial probability distribution. The graph approximately does so, but it is slightly over-dispersed for a perfect fit (ie. not enough scores of 3, and too many 1, 5, 6).

In the next graph I have shown the harvest-quality data as a time series. Each data point represents one vintage, and the pink line is a running average (it shows the average value across groups of 9 consecutive years, thus smoothing out the long-term trends). [Technical note: the data are of ordinal type but not necessarily interval type, and so calculating an average may not actually be valid. I have simply assumed that it is appropriate, given the relatively close fit to the binomial probability distribution.]

Using the scale 0-6, the average vintage score is 3.2, whereas it would be c.3 for random data, so that the average harvest across the 301 years was slightly above expectation. There is no general long-term trend in vintage quality across these three centuries, as was also true for the Rheingau region in general (see The grand-daddy of all vintage charts). Nevertheless, Scores 1 and 2 do decrease in frequency from the 1940s onward — Score 1 occurs only in 1941, 1956 and 1965; and Score 2 occurs only in 1954, 1955, 1964 and 1984.

The next graph shows the frequency of the various starting dates for the grape harvest across the three centuries. It is worth pointing out that at Schloss Johannisberg harvest occurs several weeks after the rest of the Rheingau — this has been a deliberate strategy for a very long time, to get the grapes extra ripe.

There are actually some quite regular peaks and troughs in this graph. However, the most obvious point is the lack of harvests starting on November 1 at any time during the 301 years, which is compensated by an over-abundance of starts on November 2. Of course, All Saints' Day (or All Hallows' Day, Allerheiligen) falls on 1 November. This an optional holiday that is officially observed only in parts of Germany. Indeed, this day is a public holiday in the states of Baden-Württemberg, Bayern, Rheinland-Pfalz, Nordrhein-Westfalen and Saarland. However, the Rheingau is in the state of Hessen, instead, where November 1 is not an official holiday. So, everywhere else in the vineyard area along the Rhine and Mosel rivers All Saints' Day is an official holiday, but not here! That doesn't seem to have ever stopped the locals from taking a day off, though, does it?

The next graph shows the time course of the vintage start dates, with the dates simply numbered from 1 as the earliest observed date. Once again, the pink line is a running average. [Note that for some years an exact start date was not specified.]

These dates are spread across more than seven weeks, from earliest to latest. The latest dates occurred at the end of the 1800s, which was the end of the global cold period known as the Little Ice Age (1300-1850 CE). More importantly for modern global warming, the harvests have generally started earlier from the 1960s onwards. The last November harvest start was in 1955; and since 1965 there have been only two years when the harvest was started in the last week of October. The first September harvest start for three centuries occurred in 1976.

The final graph shows the time course of the vintage harvest quantity.

Obviously there is a sudden and inexorable increase in grape yield at the beginning of the 1930s. This does not appear to coincide with the purchase of extra land or any other increase in vineyard area. Indeed, I can find no mention of this change at all in the book from which the data come. However, Karl Storchmann (American Association of Wine Economists Working Paper No. 214. 2017) shows that the same trend applies to all of Germany; and he suggests "changes in production technologies or climatic conditions as potential drivers."

Finally, we could compare the harvest quality scores from this single vineyard with the quality scores for the Rheingau as a whole, as listed in the previous blog post (The grand-daddy of all vintage charts). Oddly, correlation analysis indicates that the relationship between these scores is extremely poor — only 12% of the variation in scores is related between the two datasets. That is, good years in the Rehingau as a whole are not necessarily good years for Schloss Johannisberg, and vice versa.

The Rheingau — the grand-daddy of all vintage charts

Most of us probably think that vintage charts, which give a quality score for each vintage in a particular wine region, are a fairly modern thing, along with the idea of giving a quality score to each producer's wines.

Nevertheless, I have previously discussed long-term continuous records of vintage quality for several vineyard regions, including century-long recording for Bordeaux, in southern France (Two centuries of Bordeaux vintages — Tastet & Lawton) and Piemonte, in northern Italy (A century of Barolo vintages — Fontanafredda; More than a century of Barolo vintages — Marchesi di Barolo).

Intriguingly, the oldest known continuous vintage-quality record is for the Rheingau region in southern Germany, covering the years 1682-1884 CE, which thus includes scores for 203 consecutive vintages.

The Rheingau

The Rhine River generally flow north from the Alps to the North Sea. However, at one point it turns west, having encountered the southern part of the Taunus plateau. After 20 km or so it breaks northwards again, between the Taunus and Hunsrück plateaus, forming the best known part of the river, the Romantic Rhine so beloved of tourists, with the old castles on the tops of the river gorge, and even in the river itself.

The east-west part of the river is the Rheingau, with most of the vineyards on the gently sloping south-facing slopes next to the river itself.

As Stuart Pigott recently noted about the period covered by the vintage chart:

The Rheingau may be much older than the Medoc in Bordeaux, for example, but the most decisive period of its history came in the 18th century, beginning with the world’s first varietal plantings of the Riesling grape, the introduction of late harvesting, and the selective harvesting of bunches. All of this happened at the same property: Schloss Johannisberg, in 1720-21, 1775 and 1787, respectively. [Down the road, Schloss Vollrads is the oldest operating commercial winery in the world, with its first documented release of wine in 1211 CE.]

For a century following the breakthrough vintage of 1811, Rheingau Rieslings were the most sought-after and expensive wines in the world. By the 1850s, the Rheingau was on a roll. The majority of the region’s wines were dry, but those that wrote the headlines were sweet wines made from nobly rotten grapes. Then, at the end of the 19th century, it was overtaken by the Mosel.

Vintage chart

The vintage chart in question appears as Table V of a book called Karte und Statistik des Weinbaues im Rheingau, compiled in 1885 by Heinrich Wilhelm Dahlen. This book is available online at the Landesbibliothekszentrum Rheinland-Pfalz.

The chart itself is entitled Uebersicht von Menge und Güte der Wein-Erträge in dem vormaligen Herzogthume Nassau in den Jahren 1682 bis 1884 (Overview of the quantity and quality of the wine-income in the former duchy of Nassau in the years 1682 to 1884). A direct link to the chart is available here.

The chart uses a color code to indicate the wine quality for each vintage, along with a written indication of the quantity of the harvest. The quantity is indicated by words in the first three columns of the chart, but there are actual volumes (in hectoliters) in the final column; the length of the colored bars in the final column also indicates the quantity. The 4-point quality color code is:

Vorzüglich Gut Mittelmäßig Gering und schlecht

excellent good mediocre (or fair) poor and bad

red light green brown dark green

In the rest of this post, I provide a transcription of this vintage chart, along with some analysis of the data. Thanks to the Hogshead blog (Buy 1684, avoid 1687: an historic German vintage chart) for drawing my attention to this extraordinary historical record.

Analysis

Here is a summary of the harvest-quality data for the 203 vintages:

Excellent	26
Good/excellent	1
Good	50
Mediocre/good	14
Mediocre	45
Poor/mediocre	9
Poor	63

Here are the same data presented as a frequency histogram of increasing quality. For random data his would follow what is known as a binomial probability distribution. It approximately does so, but for a perfect fit there are actually a few too many vintages of the "poor and bad" sort relative to the "mediocre" sort.

In the next graph I have shown the harvest-quality data as a time series, with the quality codes converted to the scores 1-4. Each data point represents a vintage, and the pink line is a running average (it shows the average value across groups of 9 consecutive years, thus smoothing out the long-term trends). [Technical note: the data are of ordinal type but not necessarily interval type, and so calculating an average may not actually be valid. I have simply assumed that it is appropriate, given the relatively close fit to the binomial probability distribution.]

Using the scale 1-4, the average vintage score is 2.2, whereas it would be 2.5 for random data, so that the average harvest across the 203 years was slightly below expectation (as also noted above for the frequency distribution). There is no general long-term trend in vintage quality across these two centuries, which cover the second half of the global cold period known as the Little Ice Age (1300-1850 CE).

There are, however, remarkably regular peaks in quality every 25-30 years (as shown by the peaks and valleys of the pink line). The cause of this is not immediately obvious, although it is presumably related to cyclical weather patterns. The first two of the quality peaks actually run together (ie. there is no intermediate dip in quality), so that the vintages were generally good from 1700-1730.

The second graph shows the relationship between vintage quality (vertically) and vintage quantity (horizontally), with each point representing a vintage from 1830-1884. There is a general positive association between quality and quantity (correlation r=0.59), so that, for example, small numbers of grapes are never associated with the best quality score. Mark Matthews, in Terroir and Other Myths of Winegrowing (University of California Press, 2016) points out that this is often true of wine making.

Interestingly, this vintage chart is not the only presentation of the Rheingau wine quality from this time period. Karl Storchmann (2005. English weather and Rhine wine quality: an ordered probit model. Journal of Wine Research 16:105-120) has transcribed a set of verbal descriptions of vintages into a set of quality scores. His data are for a single vineyard, Schloss Johannisberg (mentioned above), covering the period 1700-2000 CE. I have not yet obtained a copy of these data, to make a direct comparison with the data shown above.

Transcription

Notes: The following is a transcription of the original Gothic script into modern German. I have translated the quality color codes using the 1-4 scores. For some of the years the score is shown as being a mixture of two different codes (eg. 1/2), as explained in the Remarks (Bemerkungen) below. The first part of the chart has only abbreviated comments about the harvest quantity (Menge = amount). The middle part of the chart also provides a score for the amount (^x⁄_x). The final part of the chart provides the estimated harvest quantity, in hectoliters. If you are interested, Google Translate does a reasonable job of translating the German text.

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Übersicht von Menge und Güte der Wein-Erträge in dem vormaligen Herzogthume Nassau in den Jahren 1682 bis 1884.

 Bemerkungen.

Wenn allgemeine Angaben über die Menge bis zum Jahre 1829 in den benüßten Chroniken*  nicht vorhanden waren, wurden dieselben weggelassen und folche nur für die Jahre eingefeßt, über welche entsprechende Mittheilungen sich vorsanden. Stimmten die diesbezüglichen Auszeichnungen nucht überein, so sind die sich widersprechenden Angaben einander gegenübergestellt.

Die Menge für die Jahre 1830 bis 1884 ist nach den officiellen Erhebungen für das Gebiet des vormaligen Herzogthumes Nassau in hektolitern angegeben und deren Berschiedenheit graphisch dargestellt. Bis 1868 wurden die Angaben benüßt, welche Bolizeirath Höhn in Weisbaden bereits in einer für die Wiener Weltausstellung 1873 zusammengestellten Tabelle ausgesührt hatte.

Die Güte ist entsprehend der Qualität der Rheingauer Weine im Allgemeinen durch die nachstehend ernähnten Farben ausgedrükt. Da die Darstellung den Charakter der Weine im Allgemeinen ausbrüken soll, so ist natürlich nicht ausgeschlossen, baß in speciellen Jällen d. h. engeren Bezirken in den betressenden Jahren auch bessere oder geringere Qualitäten erzielt wurden, als es den gewählten Farben entspricht.

Haben bis zum Jahre 1829 für denselben Jahrgang zwei Farben Berwendung gesunden, so stimmten die Angaben der Chroniken nicht überein, sondern wichen in der Weise von einander ab, wie die betressenden Farben veranschaulichen.

Die Güte für die Jahre 1830 bis 1884 wird wie oben durch Farben veranschaulicht und ist die Darstellung aus Grund der diesbezüglichen Mittheilungen eines der hervorragensten Rheingauer Weinkenner, dessen Ersahrungen bis zu dem zweiten Decenium dieses Jahrhunderts hinausreichen, ersolgt. Sind in besagtem Zeitraum für einen Jahrgang zwei Farben benußt, so bemegt sich die Güte innerhalb des hierdurch angedeuteten Werthes.

Die Qualität ist durch solgende Farben ausgedrüßt.

* Es wurden hierbei solgende Quellen benüßt:
1. Rheingauer Geschichts- und Wein-chronik. Von Dr. Rob. Haas. Weisbaden 1854.
2. Der Weinbau in Nassau. Von O. Sartorius. Weisbden 1871.
3. Der Weinbau der leßten hundert Jahre im Rheingau. Von T. B. Weinbau und Weinhandel 1885, S. 51.
4. Über das Schäßen der Weinernten. Von W. Rasch. Ebdenda S. 60.

Jahr	Score	Menge
1682	1	wenig
1683	2	wenig
1684	4	voller herbst
1685	1	viel
1686	3
1687	1	viel
1688	1	viel
1689	3
1690	2
1691	2	sehr wenig
1692	1	sehr wenig
1693	1	wenig
1694	3
1695	1	wenig
1696	1
1697	2
1698	1	wenig
1699	3	viel
1700	4
1701	3
1702	2
1703	2
1704	4
1705	1	wenig
1706	4	voller herbst
1707	3
1708	2
1709	1	starker winterfrost
1710	3
1711	3
1712	4	sehr viel
1713	1
1714	2
1715	3
1716	1
1717	2
1718	4
1719	4
1720	2
1721	1
1722	1/2
1723	4	viel
1724	3
1725	1	sehr wenig
1726	4	voller herbst
1727	3	sehr viel
1728	3
1729	3	viel
1730	1
1731	2
1732	1
1733	2
1734	2
1735	1
1736	3
1737	3
1738	4
1739	2	viel
1740	1	frühsr. viels. nicht gel
1741	2/3	wenig
1742	1	wenig
1743	3
1744	3
1745	2/3	wenig
1746	4	sehr wenig
1747	4
1748	4
1749	4	wenig
1750	4	viel
1751	1	wenig
1752	1	viel
1753	3	gehr viel
1754	2/3
1755	3	wenig
1756	1	mittelertrag
1757	2	halber herbst
1758	1	viel
1759	3	viel
1760	3	viel
1761	3	viel
1762	3/4	gehr viel
1763	1	vielfach nicht gelesen
1764	2	wenig
1765	1	sehr wenig
1766	3	viel
1767	1	sehr wenig
1768	2	wenig
1769	1	viel
1770	2	wenig
1771	1/2	viel
1772	2	viel
1773	2
1774	3	viel
1775	3	viel
1776	1	wenig
1777	1	mittelertrag
1778	2/3	wenig
1779	3	viel
1780	3	viel
1781	4	sehr viel
1782	1	biemlich viel, fruhfr.
1783	4	hauptjahr
1784	3	sehr wenig (1⁄8)
1785	1	biemlich viel (1⁄2)
1786	1	wenig (1⁄4)
1787	1	viel (1⁄2)
1788	3	viel (0)
1789	2	wenig, spätfrost (1⁄8)
1790	2	wenig (1⁄8)
1791	1/3	frühfrost, 1⁄2 herbst
1792	1/3	feblj. & spätfr. (1⁄8)
1793	1	sehr wenig (1⁄8)
1794	3	mittelertrag (4⁄8)
1795	1/2	wenig (1⁄8)
1796	1/3	wenig (1⁄8)
1797	1	wenig (1⁄8)
1798	3	viel (1⁄2)
1799	1	sr. hagelbeichädg. (1⁄8)
1800	3	sehr wenig (1⁄3)
1801	3	wenig bis viel (1⁄2)
1802	3	sehr wenig bis ziemt. viel (1⁄8)
1803	2	(2⁄8)
1804	3	sehr viel (1⁄1)
1805	1	sehr wenig (0), frühfr.
1806	4	biemlich viel (1⁄3)
1807	3	biemlich viel (1⁄3)
1808	2	viel (1⁄1)
1809	1	wenig (1⁄8)
1810	2	wenig (1⁄2)
1811	4	sehr viel (1⁄3)
1812	2	nicht viel (2⁄3)
1813	1	sehr wenig (1⁄8)
1814	2	sehr wenig (1⁄8)
1815	3	wenig (1⁄3)
1816	1	vielfach nicht gel. (0)
1817	1	wenig (1⁄8)
1818	3	mittelertrag (1⁄1)
1819	3	viel bis sehr viel (1⁄1)
1820	1	rein (1⁄2), herbst (1/3)
1821	1	unbedeutend (1⁄3)
1822	4	voller herbst (1⁄3)
1823	1	halber herbst (1⁄3)
1824	1	wenig (1⁄4)
1825	3	viel (1⁄2)
1826	3	voller herbst (1⁄1)
1827	3	sehr wenig (1⁄4)
1828	2	voller herbst (1⁄1)
1829	1	sehr wenig (1⁄6), herbst (1⁄3)
1830	1	2,700
1831	3	32,412
1832	1/3	33,840
1833	2/3	95,472
1834	4	106,368
1835	3	87,120
1836	2/3	42,768
1837	1	31,236
1838	2	21,768
1839	1/3	43,644
1840	1/2	39,660
1841	2/3	28,572
1842	2/3	67,728
1843	1	34,486
1844	1/2	34,392
1845	1	34,548
1846	4	117,000
1847	1/2	102,804
1848	3	63,264
1849	1	44,916
1850	1/2	51,216
1851	1	51,300
1852	2	53,232
1853	2	53,256
1854	1/2	9,516
1855	3	43,968
1856	1	27,888
1857	4	109,968
1858	3	97,104
1859	3	71,040
1860	1	64,800
1861	3	24,624
1862	4	96,480
1863	1	54,960
1864	1	33,612
1865	4	89,220
1866	1	99,000
1867	1/2	77,676
1868	4	129,485
1869	2	57,552
1870	2	62,616
1871	1	25,874
1872	1	11,612
1873	2	27,839
1874	2/3	84,284
1875	2/3	131,088
1876	2/3	75,070
1877	1	61,827
1878	2	37,416
1879	1	13,928
1880	2/3	14,452
1881	2/3	67,691
1882	1	38,392
1883	2/3	74,220
1884	3	76,820

Can non-experts distinguish anything about wine?

Roman L. Weil is a professor of accounting, with an interest in wine. During the early 2000s he conducted three similar experiments to assess the ability of non-experts (primarily educated, upper middle-class individuals who were experienced and enthusiastic wine drinkers) to distinguish various characteristics of wine. These distinctions included:

• vintages rated by an expert as good versus poor
• wines selected for a special "reserve" bottling versus the normal wine
• different taste descriptors provided by an expert.

Here, I summarize the results of those experiments, as they seem not to be widely known, and yet they provide very interesting conclusions. In my usual fashion, I present pictures of the results (ie. graphs) rather than the original tabulated numbers, because it is then much easier to see the patterns in the data and thus to appreciate the conclusions.


Methods

All of the experiments were designed in the same way. Several different pairs of wines were chosen for each experiment, the pairing being determined by the particular objective of each experiment; these wine pairs constitute the experimental replication. The paired wines were presented to several hundred different tasters, spread over a number of different places and occasions; these people constitute the replicate sample units.

In each case, each taster was presented with three unlabeled glasses, one glass containing one of the wines, and two glasses with the other wine from the same pair. In this triangular experiment, the taster was asked to distinguish the singleton wine (ie. one of the glasses should taste different to the other two glasses). The taster was then asked to identify certain characteristics of the two wines. On any one occasion, tasters received 1–3 of the wine pairs.

The results were summed for each wine pair separately, listing the number of people who correctly distinguished the two wines in each pair, and then how many of those successful people correctly identified the chosen characteristics. Note that distinguishing the characteristics is not relevant unless the taster could actually distinguish the paired wines in the first place!

By random chance, the tasters should be able to distinguish the paired wines one-third of the time (ie. identifying the singleton glass out of three). So, our "expected" result is 33% if the tasters can do no better than random (ie. guessing). Then, for the two characteristics the expectation is 50%, if the tasters can do no better than random (ie. there are two characteristics to identify).


Distinguishing different vintages of the same wine

Roman L. Weil (2001) Parker v. Prial: the death of the vintage chart. Chance 14(4):27-31.

The hypotheses being tested in this experiment are that the amateurs:

• cannot distinguish in blind tastings the wines of years rated by an expert as high from those of years rated low, and
• if they can, they do not agree with the vintage chart's preferences.

To test these hypotheses, Weil selected six "pairs of wines with the following characteristics: the pairs have identical features (such as shipper, vineyard, and producer) except vintage, and Robert Parker rated one the vintages of those two wines Average to Appalling while he ranked the other Excellent to The Finest in The Wine Advocates Vintage Guide 1970-1999." So, the only difference between the paired wines should be that they came from vintages that Parker thought were very different from each other.

There were 593 tasters. One of the wine pairs was presented to wine professionals ("experts") on two occasions, as well as to the amateurs on the other occasions, and so these experts are treated separately in the results. The pairs of wine were tasted by 54-119 tasters each.

The results of the first hypothesis test are shown in the next graph. For each of the graphs presented below, the interpretation is as follows. Each wine-pair is represented by a horizontal line, as indicated by the legend. The central point on each of the lines represents the percentage of the tasters who succeeded at the task for that wine pair. The two end points on each line are the boundaries of the estimated 95% confidence interval (formally: the Score binomial 95% confidence interval). This interval gets smaller as the sample size (the number of tasters) gets larger, as it represents our statistical "confidence" in the results of the experiment. The dashed line represents the expected results if the tasters are performing in a random manner — the idea of the experiment is to see whether people can do better than random. So, if the dashed line passes through the 95% confidence interval for a particular wine pair, then the tasters have done no better than random for that pair, whereas if the dashed line lies outside the 95% confidence interval then the tasters have done better than random.

For the first graph, only the two groups of tasters receiving the Bordeaux wine performed better than random chance. Formally: for five of the wine pairs, the experiment provides no evidence that amateur wine tasters can distinguish between good and poor vintages any better than taking a guess. For the Bordeaux wine pair, both the amateurs and experts did better than taking a guess, with the wine experts doing slightly better than the amateurs.

This outcome calls into serious question the alleged difference of quality between different vintages in the modern world. Remember, Robert Parker (or his delegate) detected big differences in the vintages within a wine pair, but the amateurs could not consistently detect this for themselves when presented with actual examples of the wines. The different result for the Bordeaux wines may reflect the common conception that vintages really do still differ in Bordeaux.

The results of the second hypothesis test are shown in the next graph, which is interpreted in the same manner as described above. Remember that the data here refer only to those tasters who successfully distinguished the wine pairs, which is 30-50% of the tasters. The sample sizes therefore refer to only 21-60 tasters per wine pair.

Note that in all cases the tasters behaved in a random manner. That is, there was no consistent preference for the wine from the highly rated vintage compared to the poorer vintage, for any of the wines. We may conclude from this that expert vintage ratings are not related to wine preferences among wine drinkers. The wine from an allegedly poor vintage can taste just as good to an amateur drinker as a wine from a supposedly better vintage.


Distinguishing reserve and normal bottlings of the same wine

Roman L. Weil (2005) Analysis of reserve and regular bottlings: why pay for a difference only critics claim to notice? Chance 18(3):9-15.

The hypotheses being tested in this experiment are that the amateurs:

• cannot distinguish in blind tastings the wines of reserve bottlings (or first wines) from the normal wines (or second wines), and
• if they can, they do not prefer the reserve wine.

To test these hypotheses, Weil selected fourteen "pairs of wines based on the following characteristics: the pairs had identical features in all respects, except that one was a regular bottling and one was a reserve bottling. Common features included all label items (e.g. shipper, vineyard, and producer), retail source, and date of purchase." So, the only difference between the paired wines should be that the winemaker specially selected the reserve or first wine for separate bottling, at a much higher price (there was a price ratio of 1.13-3.57 for Weil's choices).

The results of the first hypothesis test are shown in the next graph, which is interpreted in the same manner as described above. There were 855 tasters, with the pairs of wine being tasted by 38-136 tasters each. The two pairs of Champagne wines were each tasted by a small number of people only, and so I have pooled their results here (they did not differ from each other).

Note that the tasters do very much better here than in the previous experiment. That is, for six of the thirteen wine pairs the tasters did better than random when asked to distinguish the more expensive bottle of wine from the same winemaker. Mind you, they rarely did better than 50%, as opposed to 30%. Interestingly, there are three wine types that are repeated in the experiment: the cabernet blend from Bordeaux, the cabernet wine from the western USA, and the white wine from California; and in all three cases the tasters succeeded with one wine but not the other.

Nevertheless, the results do indicate that, for tasters, there is often a bigger difference between what the winemaker does with the wine (selects wine for different bottlings, to be charged at different prices) than between what nature does with the wine (produces different climatic conditions in different years).

The results of the second hypothesis test are shown in the next graph. Remember that the data here refer only to those tasters who successfully distinguished the wine pairs, which is 30-50% of the tasters. The sample sizes therefore refer to only 13-56 tasters per wine pair.

Here, the tasters did not consistently prefer the reserve wine over the normal wine, except in two cases. We may conclude from this that winemakers are, indeed, generally selecting wines of different taste for their different bottlings, but that this is not necessarily related to wine preferences among wine drinkers. The wine from an expensive bottle can taste just as good to an amateur drinker as one from a supposedly inferior bottle of the same wine.

The two exceptions are informative. For one of the California chardonnays there was a strong preference for the more expensive wine. This suggests that the winemaker succeeded in this particular case — they charged more ($26 versus $13) for a wine that drinkers actually prefer. In the opposite manner, for one of the Bordeaux wines there was actually a preference for the cheaper wine. It may surprise you to reveal that this was a preference for the 1994 Les Forts de Latour ($56 at the time) over 1994 Château Latour ($200), the most expensive wine in the experiment. The Bordeaux first-growth chateaux might like to take note of this result (as might your wallet!). (Note: in general, the first wines of the Bordeaux first growths cost 3-4 times as much as their second wines; see the Liv-Ex blog.)


Matching wines and their descriptions

Roman L. Weil (2007) Debunking critics' wine words: can amateurs distinguish the smell of asphalt from the taste of cherries? Journal of Wine Economics 2:136-144.

The hypotheses being tested here are that the amateurs:

• cannot distinguish in blind tastings wines that are described by an expert using different words, and
• if they can, they cannot match the descriptions to the wines.

To test these hypotheses, Weil selected ten "pairs of wines with the following characteristics: the pairs have similar features, and the same writer / critic wrote about these two wines with disjoint word sets. That is, the reviewer used different words in describing the two wines." Note that the wines could actually come from different vintages or even continents, provided that they had similar grapes, etc.

The results of the first hypothesis test are shown in the next graph, which is interpreted in the same manner as described above. There were 321 tasters, with the pairs of wine being tasted by 13-86 tasters each, which means much smaller sample sizes than for the other experiments.

Since the objective was to choose wines that differ in description by an expert, it is hardly surprising that the tasters succeeded in distinguishing the wine pairs in six out of the ten cases. However, in only one case did they do better than 60-70%, which does call into question the experts' abilities to describe wine in any quantitative way. After all, there are many examples in wine lore of different experts also describing exactly the same wine in completely disjunct words.

The results of the second hypothesis test are shown in the next graph. Remember that the data here refer only to those tasters who successfully distinguished the wine pairs, which is 40-60% of the tasters. The sample sizes therefore refer to only 5-45 tasters per wine pair.

Sadly, in only one case could the tasters consistently match the wines to the expert descriptions. So, we may conclude that reading a description of a wine does not necessarily tell you what it will taste like to you.


Conclusions

Combined, these three experiments do not paint a happy picture of the wine business. Amateur wine tasters cannot consistently distinguish wines from different vintages or different bottlings, or with different descriptions. And when they can do so, their preferences do not necessarily agree with the professionals' assessments of quality —  they are about as likely to prefer the one as the other. So, what is it that these professionals are doing? Whatever it is, it seems to be somewhat divorced from their customer base. In any case, there seems to be little reason to pay more for a "special" wine (a better year or a better selection), unless you have already checked it out and decided that you prefer it.


Quality versus preference

One potentially confusing aspect of Weil's experiments is that in two of his three experiments his second hypothesis is not actually related to the first one. In the first experiment his second question concerns which wine the tasters prefer, not which one they think is from the higher-rated vintage; and similarly for the second experiment, they are asked which wine they prefer rather than which one is the reserve wine. Only in the third experiment is the second question directly related to the objective — which wine matches which description.

It is important to recognize the distinction between "prefer / like" and "high quality" (otherwise, one of the two expressions would be redundant!). These are often treated as though they both mean "better", as in the expression "if you like it then it is good". However, these are two very different ideas — supposedly better quality does not mean that you should prefer it in any personal sense. Personal preference is all in your head, but differences in quality also exist outside of it.

For example, one does not need to like opera in order to recognize a poor opera singer, nor does one have to be a practicing christian to appreciate the architectural and artistic merits of a church. So, recognition of quality is not necessarily related to personal choice. For example, I can accept that there are high-quality characteristics of Champagne, but I do not actually like the taste of those distinctive characteristics — I actually prefer the crémant wines from Alsace, Die or the Loire, or the sparkling wines of southern Australia. Financially, of course, this is to my benefit!

This point is important for a wine drinker. The ability to recognize which wine the professionals think has higher quality is a separate issue from whether you actually like that wine. Do I like the wines recommended by Robert Parker? Perhaps so, or perhaps not, but either way I can probably recognize them, because they have a similar set of characteristics. He sees those characteristics as denoting high quality, but I may well see them as something I don't particularly care for.

Weil is probably right to focus on "prefer / like", since that is of most practical relevance to a consumer; but we should not confuse this with "quality". It would be of interest to experimentally examine the latter, also.