It’s King’s Day in the Netherlands and orange is everywhere. This not only applies to shirts, flags and decorations, but also to wine. With a very lively natural wine scene including orange wine evangelist Simon J. Woolf and plenty of Gen Z hipsters roaming the canals, it feels like orange wine has staged a coup and is the new pretender to the throne of the wine world. Internationally, the wine press has written about the orange wine trend for the last 10 years. And this year even the notoriously conservative WSET put orange wine in the spotlight by making it a topic for the D6 individual research assignment.

But step outside the hipster-dense Ring of Amsterdam or the natural wine enclaves of East London and Berlin Kreuzberg and the narrative shifts. In the provinces and in more traditional restaurants, orange wine is still a ghost. And when speaking to the old guard of wine professionals, orange wine is quickly dismissed as something flawed and cider-like that no serious wine lover would actually enjoy.

This made me curious: how big is orange wine these days? Information on wine sales in general and orange wine in particular is notoriously scarce so it wasn’t easy to find actual data that support or refute the “big trend” and “orange is the new rosé” story line. Time to get creative and come up with some measures to quantify the amber revolution.

A decade of steep growth

The first idea to measure peoples’ interest in orange wine is to look at Google Trends. The data shows that search interest in 2026 is about three times higher than it was in 2015. Quite a large increase but maybe less than I expected based on the orange craze in Amsterdam. Google trend data has some limitations (see, for example, Hölzl et al, 2025), so let’s dig deeper.

As an avid user of CellarTracker, I thought I’ll check the number of orange wines on the platform. CellarTracker tends to be used by fine-wine collectors who write tasting notes and keep track of the bottles in their cellars. Not a demographic I would immediately associate with orange wine, but let’s find out.

To see how the orange wine category has grown over time, I use the advance search functionality of CellarTracker to find the number of orange wines for each vintage since 2010.1 Again there is a steep increase, maybe this time a bit earlier than indicated by Google Trends and somewhat slowing in recent years. But the magnitude of the increase is similar with 3.7 times more different orange wines in 2022 than in 2015 (Note that numbers in more recent vintages may be incomplete because not all wines have been released or logged by the users yet.)

While the growth in search interest was lower than expected, the increase here is more than I initially thought it would be. When even the traditionalist CellarTracker crowd is logging more and more orange wine, this is definitely evidence for significant growth that goes beyond the hipster bars.

Orange wine production going global

Let’s try to understand a bit better where this growth comes from. In the early 2010s, most orange wines were produced in the traditional regions of Friuli-Venezia Giulia and Eastern Europe. While the number of wines from these regions has grown, the increase was moderate and can only explain a small part of the overall rise in the category.

Most of the increase in the number of orange wines actually comes from outside the traditional regions — the amber revolution has gone global. From 2014 to 2018 orange wines from other European regions started to grow heavily, later followed by the rest of the world. Nowadays, orange wine is produced on all continents in over 50 countries worldwide from Armenia to Canada and Peru to Japan. And it’s not Eastern Europe but the usual suspects of Italy, France and the USA who produce most wines.

Still a small niche

While there clearly seems to be growth, this doesn’t mean orange wine is big. Let’s put the numbers into perspective. There are millions of wines on CellarTracker and only less than 1% of them are orange.

While the share has increased from a tiny 0.2% in 2015 to a slightly less tiny 0.7% in more recent vintages, the overall market share remains very small. In comparison, rosé is about 10x as large and continues to grow at an even faster pace than orange wine.

Looking outside the Cellartracker fine wine bubble, there is more evidence that the orange wine remains niche. Since 2021 orange wine has a category in the Decanter World Wine Awards and all submissions are listed on their website. In the first year, a mere 25 orange wines were submitted. This has quadrupled to 108 in 2024 (before falling again to 84 in 2025), but with around 14,000 submissions every year, the share is again tiny. Interestingly, the share fully aligns with what I found on CellarTracker, ranging from 0.17% in 2021 to 0.71% in 2024. Rosé is again around 10-times as large, making up between 5.4% and 6.0% of submissions.

So the clickbaity headlines that “orange is the new rosé” are clearly exaggerated. While we are debating whether orange wine should be called orange, amber or skin-contact white wine, a much larger part of the world is enjoying the sun while sipping pale rosé.

The verdict

Ultimately, the data shows that orange wine is neither a fleeting anti-establishment phenomenon nor a fully established fourth category on par with white, red and rosé yet. It’s a high-growth niche that has successfully globalized. And even if the are signs that growth may have slowed down somewhat in recent years, that counts for something, especially in a time when the overall wine market is struggling.

As the King's Day party people pack away their orange polyester, the amber bottles remain. Not as a mass-market takeover, but as a niche category that is more and more becoming part of the modern cellar.

References

Johanna Hölzl, J., Keusch, F. and Sajons C. (2025). The (mis)use of Google Trends data in the social sciences - A systematic review, critique, and recommendations. Social Science Research, 126, 103099

Did I forget an important factor in my previous post in which I concluded that there is no relation between perceived wine quality and the phases of the moon? Could it be that sulfites, filtration or stabilizion make wines taste the same on every day and rob them of the relationship with the moon? This is what a couple of commenters including wine writers Wink Lorch and Dennis Lapuyade suggested in response to an article by Jamie Goode. I see some grumpy old wine snobs already frowning because that concept sounds even more esoteric than Maria Thun’s calendar on its own. But let’s keep an open mind and find out.

Luckily, the data I analyzed includes wines from Foillard, Lapierre, Occhipinti and other producers who are known for their low-intervention style. So on top of the “Fancy Wine Effect”, the “Weekend Effect”, and the “General Biodynamic Calendar Effect”, I can also look at whether we see differences in scores depending on the moon specifically for “natural” wines.1

The results are pretty much the same: there is no statistically significant effect of the biodynamic calendar on wine scores, even when looking separately at natural wines. While at first sight the average score seems to be highest on Fruit Days, the difference is statistically indistinguishable from zero: the light-blue bars that visualize uncertainty clearly cross the zero line.2

Did I forget, anything else? To be sure, it’s always a good idea to check the literature and see what wine academics have found using carefully designed experiments. Compared with statistical analysis, the advantage of controlled experiments with expert tasting panels is that it allows the researchers to control for various confounding factors. The downside of course is the much smaller number of reviews and tasters.

The main experimental study on the subject of the biodynamic calendar and wine tasting was published already in 2017 by Wendy V. Parr and her colleagues (Parr et al, 2017). For their paper “Expectation or Sensorial Reality? An Empirical Investigation of the Biodynamic Calendar for Wine Drinkers,” the researchers had 19 professional wine tasters blind-taste the same Pinot Noirs multiple times on different days without knowing which were supposedly “favourable” or “unfavourable” days for tasting. The results showed that while the tasters’ perception varied across days, their preferences and descriptions had nothing to do with the biodynamic calendar. The punchline:

“The current study found no evidence to support the notion that wine tasters’ evaluations of a wine’s sensory attributes are influenced by the lunar cycle.”

Parr et al, 2017

Ultimately, the study suggests that if someone perceives a difference on Fruit Day vs Root Days, this is likely a “placebo effect” driven by expectation rather than any actual change in the wine’s flavor. We still have lunar permission to taste every day — we just shouldn’t check the biodynamic calendar beforehand to avoid that our mind plays tricks on us.

So what does affect our perception of a wine?

If the biodynamic calendar is not responsible, why does the same wine sometimes taste differently on different days? There are actually a number of reasons with more solid scientific backing.

Our body

We aren’t the same taster every day. Our mouth is a complex chemical environment, and even minor shifts in our biology can change how a wine lands on the palate. For instance, certain medications or a simple nutrient deficiency can tweak the composition of our saliva, making us more sensitive to bitterness. Also when saliva flow is reduced, for example due to dehydration, a wine can feel more astringent (Wang et al, 2024). Stress has been shown to actually dull our ability to perceive sweetness (Al’Absi et al, 2012). In general, taste sensitivity isn’t fixed. It fluctuates with hormone levels, which can lead to daily, monthly and seasonal patterns (Costanzo, 2024). And much like how everything in the grocery store looks delicious when you're starving, hunger also affects the taste of wine (Fu et al, 2021).

The world around us

It’s not only us, it’s also the world around us that affects our senses. Loud or rough noise can distract the brain, dulling the perception of sweetness and making the alcohol feel more prominent. On the flip side, the right music can act as "sonic seasoning," priming the brain to perceive a wine as more powerful or refreshing (North, 2012; Wang and Spence, 2017). The very air you breathe plays a role, too. Various studies have shown how humidity, air pressure and ambient temperature affect how volatile aromatic compounds escape the liquid and thus affect our taste perception (for example, Hummel, 2011 and Burdack-Freitag and Bullinger, 2010).

The tasting setup

Of course, as every wine lover knows, aromas depend quite heavily on the wine glass. The infamous champagne flute is fine for bland Prosecco, but you will not be able to enjoy the complexity of a special bottle of champagne. Also the order of tasting matters due to the so called carry-over effect: the taste of a previous wine influences our perception of the current one (Durier et al 1997). For example, if you move from a high-acid wine to a medium-acid wine, the second can feel somewhat flat. Any food you eat before or during the tasting has a strong effect as well. For example, proteins in meat can bind tannins and make a wine feel less astringent. Lastly, during a long tasting, sensory fatigue may set in, meaning that after repeated sips, your receptors may tune out and perceive a wine as less complex (Rolls et al, 1981).

The wine

And of course we shouldn’t forget that the wine actually might not be exactly the same from one tasting to the next. One bottle might have been filled from the top of a barrel whereas another one came from the bottom, leading to some batch variation. Furthermore, bottle variation might come from heat during transport, light on the shelf or an imperfect closure. So even when the bottle looks the same, it doesn’t mean that the liquid inside is exactly the same as during a previous tasting.

This long (and most likely incomplete) list nicely shows that taste perception is complex. There are a zillion factors that can explain why your favorite bottle might taste a bit off one day. So don’t blame the moon — try to relax with your favorite playlist, hydrate, grab a salty snack or simply switch your glassware. Science suggests that these tweaks have a much higher chance to improve your tasting experience than waiting for the next Fruit Day.

References

Al’Absi, M., Nakajima, M., Hooker, S., Wittmers, L. and Cragin, T. (2012) Exposure to acute stress is associated with attenuated sweet taste, Psychophysiology, 49(1), pp. 96–103.

Burdack-Freitag, A. and Bullinger, A. (2010) Odor and taste perception at normal and low atmospheric pressure in a simulated aircraft cabin, Journal für Verbraucherschutz und Lebensmittelsicherheit, 5(2), pp. 139–146.

Costanzo, A. (2024) Temporal patterns in taste sensitivity, Nutrition Reviews, 82(6), pp. 831–847.

Durier, C., Monod, H. and Bruetschy, A. (1997) Design and analysis of factorial sensory experiments with carry-over effects, Food Quality and Preference, 8(2), pp. 141–149.

Fu, O., Minokoshi, Y. and Nakajima, K.I. (2021) Recent advances in neural circuits for taste perception in hunger, Frontiers in Neural Circuits, 15, p. 609824.

North, A.C. (2012) The effect of background music on the taste of wine, British Journal of Psychology, 103(3), pp. 293–301.

Parr, W.V., Valentin, D., Reedman, P., Grose, C. and Green, J.A. (2017) Expectation or sensorial reality? An empirical investigation of the biodynamic calendar for wine drinkers, PLOS ONE, 12(1), p. e0169486.

Rolls, B.J., Rolls, E.T., Rowe, E.A. and Sweeney, K. (1981) Sensory specific satiety, Appetite, 2(2), pp. 103–121.

Wang, Q. and Spence, C. (2017) Assessing the influence of music on wine perception among wine professionals, Food Science & Nutrition, 6(2), pp. 295–301.

Wang, S., Smyth, H.E., Olarte Mantilla, S.M., Stokes, J.R. and Smith, P.A. (2024) Astringency and its sub-qualities: a review of astringency mechanisms and methods for measuring saliva lubrication, Chemical Senses, 49, p. bjae016.

During a recent boozy lunch with wine friends I noticed that the wines somehow felt muted. A friend pulled out the “When Wine Tastes Best” app to check the biodynamic calendar and, oh no, turns out it was a Root Day. Could it really be true that wines taste better on certain days depending on the positions of the moon and planets? Given my rational brain and science-based background I usually struggle with such esoteric astrological wisdom. Yet, this was the third Root Day in two months that a wine didn’t taste great. My curiosity was triggered!

Reading up on biodynamics

First I needed to read up on the biodynamic calendar of Rudolf Steiner and Maria Thun. In short, it assigns each day a “type” (Root, Leaf, Flower, Fruit) depending on the lunar cycle. For example, when the moon passes in front of Earth constellations (Taurus, Virgo, Capricorn) a plant’s energy is said to be directed towards its roots. In contrast, the energy is directed towards bearing fruit when the moon is in front of Fire constellations (Aries, Leo, Sagittarius). Biodynamic growers choose their activity in the vineyard based on the type of day.

Later, Maria Thun hypothesized that since wine is a "living" biological product, it remains sensitive to the same cosmic rhythms that affect the vine it came from. As a consequence, the same wine tastes differently depending on the type of day. Nowadays, many reputable wine makers, wine merchants and wine enthusiasts follow her theory and are convinced that the moon influences the taste of wine.

Fruit and Flower Days are said to be the best times to enjoy our favorite beverage. On Fruit days, wines are most expressive and show their full range of aromas and flavors. Flower Days are great for aromatic whites and elegant reds as they bring out delicate floral notes. In contrast, it’s best to keep the bottle closed on Root Days and Leaf Days. On Root Days, wines tend to be dull with high tannin and muddy, earthy character. Leaf days bring out more vegetal and herbaceous qualities that are often less desirable.

Is there some truth behind these anecdotes and personal experiences? It’s a romantic idea — the wine in your glass is in sync with the rhythm of the distant orbit of the moon — but is it a measurable one? Or is it just “witchcraft” as the Italian Nobel-winning physicist Giorgio Parisi famously stated about biodynamics?1 Let’s look at some data!

The Smoking Gun? A First Look at the Data

To get a first idea if there is a relation between the taste of wine and the biodynamic calendar I checked Cellartracker and looked at the scores for a randomly chosen wine with many reviews, the 2011 R. López de Heredia Rioja Reserva Viña Tondonia.

Here is the average Cellartracker score for each of the four types of day.2

Interesting! At first glance, Figure 1 is a win for the biodynamic calendar. There seems to be a difference in depending on the type of day — exactly what the theory predicts. The wine scores highest on Fruit Days with an average score of 92.1. Flower Days come second with an average score of 91.9. On Root Days and Leaf Days the scores are lower with average scores of 91.7 and 91.6, respectively.

SPOILER ALERT: The “pattern” might just be a mirage. In data science there is always uncertainty involved and it’s still possible that the result is simply due to chance. This uncertainty is visualized in the figure by the blue bars. We can be 95% sure that the true score is somewhere in the indicated range. And because the bars for even the highest and lowest days overlap, we cannot rule out that the apparent “Fruit Day” win is just caused by a lucky roll of the dice and the "real" scores for both days could actually be exactly the same.

Do wines really taste worse on Root Days?

To find out if the pattern is real, we need more than just one wine. We need to shrink those blue bars until there’s nowhere for the truth to hide. So instead of only checking the reviews for the 2011 Tondonia, I collected reviews for more wines - more than 300 to be precise. With more reviews, chance is less likely to play a role and we can get a better idea how the average score of a wine depends on the type of day. For instance, it becomes more likely that the critical tasters drink wine equally often on each type of day. The same argument holds for weather, mood, stress level, food they ate before, etc.

When we combine reviews from different wines, we cannot simply look at averages. Instead, we need to use some statistics and build a so called regression model. But don’t worry, I’ll spare you the equations.3

To find out if the moon actually changes the taste of wine, my model accounts for the “Fancy Wine Effect” and the “Weekend Effect”. We know some wines are simply better than others independent of when they are drunk. By locking in the wine's quality first, my model ensures that a Root Day doesn't look bad just because someone happened to drink a Bourgogne Rouge that day, while a Fruit Day looks good because someone popped a Grand Cru.

We know from psychology, that people generally experience better moods from Friday evening to Sunday afternoon (Ryan, Bernstein, and Brown, 2010). On weekends, we are usually more relaxed, often eating better food, and sharing wine with friends. On Tuesdays, we are often tired or stressed. If people give higher scores on Saturdays simply because they are happy, and Saturday happens to be a "Fruit Day," a simpler model would wrongly credit the moon. My model says, "Adjust for the fact that it's Saturday first—now, is there still a lunar effect?"

Once, we have “vacuumed up” the “Fancy Wine Effect” and the “Weekend Effect”, what’s left over is the pure effect of the biodynamic calendar. If the moon matters, we should see differences in scores even after we’ve accounted for the wine in the bottle and the day of the week.

The verdict? Once we crunch the numbers and put the more than 10,000 reviews through the statistical vacuum, the “Lunar Effect” doesn't just shrink — it effectively disappears.

In the figure, Root Day is our “ground floor.” Every other bar shows whether wines scored better or worse than on a Root Day. Note the scale on the left: Even the "highest" performing day, Flower, only improved the score by 0.08 points — an amount so small it would be imperceptible to even the most trained palate. Moreover, every single light-blue bar crosses the zero line. In plain English, this means the difference is so small that it’s statistically indistinguishable from zero. So, even though the average score on Flower Day looks marginally higher, the statistics say that we cannot conclude that it is actually different.4

Conclusion: Permission to pop the cork anytime

Lo and behold the relation between perceived wine quality and the biodynamic calendar seems to belong to the world of esoteric fiction rather than reality.

It’s a fun anecdote that I had three experiences with muted wines on days that in hindsight turned out to be Root Days. But it’s just that: a fun anecdote without any deeper meaning. One (or three) swallows do not make a summer.

What we “know” about wine and the moon is built on what Kahneman (2011) calls the Law of Small Numbers — the cognitive trap of believing that a few vivid tastings represent a universal law . As humans, we are also biologically prone to the Narrative Fallacy (Taleb, 2007). We would rather invent a cosmic story about a “Root Day” than accept the boring reality of random bottle variation or a taster’s bad mood.

But with more than 10,000 data points, we can move past the anecdote. In my statistical analysis I did not find any evidence that people score wines differently depending on the phases of the moon.

So let’s forget the biodynamic calendar and trust our palates instead. Every day is a good day to pop a cork—no lunar permission required.

References

Kahneman, D. (2011). Thinking, Fast and Slow. Farrar, Straus and Giroux.

Ryan, R. M., Bernstein, J. H., & Brown, K. W. (2010). Weekends, Work, and Well-Being: Psychological Need Satisfactions and Day-of-the-Week Effects on Mood, Vitality, and Physical Symptoms. Journal of Social and Clinical Psychology, 29(1), 95–122.

Taleb, N. N. (2007). The Black Swan: The Impact of the Highly Improbable. Random House.