Beer, seasonality, and seasonal beers

Seasonality in food is often addressed with reference to vegetables and fruits and their natural growing seasons. In this post I will look at seasonality in relation to a processed food, namely beer. I will start by looking briefly into the history of beer, and try to track signs of seasonality. I will then turn to the present, and explore whether and how beer consumption and production still fluctuates throughout the year. Next, I will describe typical seasonal beers that are well-known in the Netherlands and explore what makes such beers ‘seasonal’ – are they seasonal because they rely on the growing seasons of particular ingredients, or does seasonality have a different meaning in contemporary seasonal beers? Finally, I will briefly touch upon the ongoing ‘craft beer revolution’, which has also created new interest in seasonal beers, and where seasonality appears to have a strategic value for small brewers. Beer’s history in relation to the seasons Not much has been written about the history of beer with a focus on seasonality. For what I describe below, I make use of several sources on the history of beer and its production, each of them offering sparse insights about seasonal aspects of beer. I organise these insights around three topics: the seasonality of cereals, the seasonality of the fermentation process for producing beer, and some reflections on how hop contributed to ‘de-seasoning’ beer. De-seasoning refers to the process of how production and consumption become less and less dependent on the conditions that the natural seasons create. Seasonality of cereals – In Prehistoric times there were no ‘beer’ and ‘wine’ traditions yet, but a wide variety of fermented beverages were available. What was used in the brewing of these beverages depended on what fermentable products were available³. Such beverages were likely to be seasonally dependent. The brewing of beer, which came to be a tradition much later, was dependent on the availability of cereals, which was and still is the main ingredient of beer. Cereals became broadly available with the agricultural revolution. While cereals had their particular harvest seasons, and there were techniques available to dry and store the them, little seems to be written about to what extend these stored cereals were available throughout the seasons for the purpose of brewing beer. Seasonality of the fermentation process – Another historical aspect of seasonality of beer concerns the fermentation process. Fermentation is a process of transforming sugars into alcohol, carbon dioxide and other components. The yeast that is used in beer brewing has a long history, going back thousands of years. Modern yeast populations are a result of admixture between different domesticated populations that were transferred via the Silk Route¹⁴. A general distinction is often made between bottom- and top fermentation, or bottom- and top yeast. Top fermentation was, for a long time, the dominant fermentation process and the resulting beer is currently known as ‘ales’. The use of bottom fermentation, now used to produce ‘pilsner’ and ‘lager’, while known in the Middle Ages, was mostly restricted to the region in and around Bohemia (now the eastern part of Czech Republic). Unger, p.6: “Bottom yeast requires a lower and more consistent temperature to function than the other type of yeast, and until mechanical refrigeration became practical in the 1870s, its use was restricted to colder seasons of the year and regions where cooler temperatures could be expected.” Hop as a strategy for de-seasoning – While hop was already cultivated in the early middle ages, its use appears to have been mainly medicinal. There is some evidence for sparse use of hop in beer in the 9th century. Only in the 13th century, its use became more popular, as described by  Unger² (p55): “it is possible to say that by the thirteenth century [hops] were widely cultivated throughout northern Europe and had different uses, among them replacing gruit or other herbs in the making of beer.” One of the main reasons for hop’s success was that it made beer last longer (i.e. resulting in a more reliable product) and thus also travel further and being better ‘marketable’. Unger elaborates: “Preservation of foods was one of the greatest problems of pre-nineteenth-century Europe. The addition of hops in the brewing process made for a significant change in beer. It now joined the few foods that would keep for months with- out becoming inedible.” Through its improved durability, hop made the consumption of beer less reliant on the seasons. Production-side seasonality of beer at present Barley is the most commonly used cereal in beer. In current barley production, a clear distinction is made between animal feed barley and malting barley. This distinction has some history: already in the 1940s these were two genetically distinct types of grain. Barley used in beer production was a more carefully selected grain than barley used for animal feed and other purposes.⁴ Compared to feed barley, malting barley has genetic qualities that benefit brewing – qualities that result in lower levels of protein and beta glucan, and higher levels of enzymes. This genetic difference also has implications for the the growing of barley: malting barley requires relatively well-managed growing conditions compared to animal feed barley. Barley is a cool season crop, for which ultimate conditions for germination and growing are between 12 – 24 ̊C. This means that barley is either sown in spring or fall, and there are different cultivars for both seasons. Particular to winter cultivars is that they undergo a period of vernalisation (cold exposure) before they can flower in the spring. Barley is a short-season crop: after emerging, plants need 60-90 days to grow mature. Planting barley needs good timing. For the spring cultivars, early planting reduces the risk from drought stress, high temperatures, diseases and insect infestations, while delayed planting increases the risk of high protein content (which is undesirable for malting) and decreased yields⁵. The choice for a spring or fall cultivar may depend on the climatic zone: in colder climates, barley is more easily grown over the summer, while in warmer climates it is better grown over the winter⁶. Strategic decisions may also relate to the timing of the harvest: In Europe, barley grows over the winter is harvested in the early summer, while barley that grows over the spring and summer, is harvest in the fall. The brewing of beer ultimately depends on the harvests of barley, as illustrated by recent history in the Netherlands. Barley harvests in Germany and France were low in 2016, and provided too little barley for Dutch brewers. The main reason for the low harvests was a very wet early season (first half of 2016). This led brewers, such as Gulpener in the Netherlands, to also buy barley from external suppliers outside Europe. While production was maintained, Gulpener had to make do with grains that didn’t comply with the sustainability standards that their internal suppliers of the farmers cooperative Triligran guaranteed. The bad harvests were also seen from a positive point of view. On Gulpener’s website it is written: “For the farmers as well as Gulpener this was a disappointment on the one hand. On the other hand, it is remarkable to conclude that since the founding of Triligran in 1994, this cooperative was able to meet Gulpener’s needs”⁷. The brewing of beer with particular standards or qualities is thus dependent on successful harvests of particular farms, but a globalised market allows to compensate for bad harvests. Does the seasonality of barley –i.e. it being a spring and winter crop with particular harvest times – affect beer brewing and consumption in any way? To answer this question we need to consider storage time. When dried and stored properly, barley can be stored up to 18 months. Thus, the supply of barley for the production process is managed through proper storage facilities, and has no effect on the availability of (regular) beer throughout the seasons. Furthermore, the shelf life of beer ranges from several months up to several years, depending on the type of beer – for example, the higher the percentage of alcohol, the longer the shelf life. Added up, the maximum storage time of barley, together with the shelf life of beer, means that the seasonality of barley production is compensated for and not necessarily reflected in consumption patterns. Demand-side seasonality of beer at present While the seasonality of beer production generally does not affect the seasonality of consumption, this does not mean there are no seasonal patterns in when we drink beer, or particular kinds of beer. A study in Estonia (1999-2002) on alcohol use and seasonality clearly shows a peak of beer consumption in the summer months. Their data show a strong correlation between air temperature and beer consumption (and the number traffic accidents, but let’s stay on topic)⁸.  While there seems not much to be published on this topic, similar patterns were found in a study in Montana, US (1969-1975)⁹. Other ways in which seasonality of beer consumption (or alcohol consumption more generally) may occur, is through festivities like New Year’s eve or St. Patrick’s day. In a study with college students consumption peaks were found at these days, as well as a pattern of increased consumption early in the semesters and decreased consumption during the exam periods.¹⁰ The numbers of these studies are about total beer consumption, but one can imagine that there are also nuances to be found in what kinds of beers are consumed when. I couldn’t find any data or studies that address such seasonality. Traditional seasonal beers: ‘Herfstbok’ in autumn and ‘Lentebok’ in spring While most modern beers are available throughout the year and don’t have a specific seasonal character, there are also several seasonal beers that are brewed and bought in particular times of the year. What makes these beers ‘seasonal’? I will look into ‘bokbier’ particularly, which is a beer now brewed in the autumn (i.e. ‘herfstbok’) and in spring (i.e. ‘lentebok’) – the Dutch names explicitly refer to these seasons. While bokbier originates from Germany, where they produced ‘bockbier’, Dutch brewers started brewing bokbier around 1870-1880. The timing of its availability has shifted throughout history: “for a very long time February was the traditional bokbier month. Around 1920, the annual bokbier launch date was advanced to December and later put back still further into the autumn. In recent years the date has been set on or around 21 September”¹¹. The reason for this timing does not become clear from the scarce historical documentation that is available. Explanations I could find refer to the times before mechanical refrigeration. Brewing during the summer was unproductive and sometimes prohibited, as the fermenting process required low temperatures. The first brews could start right after the summer, to eventually deliver the beer in winter. These first brews were extra strong and became to be known as ‘bokbier’, and in particular the ‘herfstbok’.¹¹ Some suggest that Lentebok has a different history¹². It was the last brew before the summer, which was made extra strong (in terms of alcohol and the use of hop) to improve its shelf life. The typical beer that resulted from this way of brewing came to be known as ‘meibok’ and then ‘lentebok’ only in the last couple of decades. Both ‘lentebok’ and ‘herfstbok’ have lost their ‘natural seasonality’ so to speak, as they do not rely on temperatures imposed by the natural seasons anymore. The seasonality that remains is of a cultural kind. The flavours and colour can also be said to be ‘seasonally appropriate’, and can be expected to have been designed that way: while herfstbok is typically described as ‘ruby red’, ‘dark’, with a ‘malty caramel flavour’, lentebok is described as a ‘bright’ and ‘fresh’ beer, with a ‘hoppy’ and sometimes ‘fruity’ flavour. In a future post I hope to learn more about seasonal flavours: To what extent are particular flavours and colours ‘imposed’ by natural seasons, either in the past or present? Or are they designed that way without reference to what’s naturally available? Seasonality and the ‘craft beer revolution’ Over the last decades we have witnessed, what has been described as a ‘craft beer revolution’ in many parts of the world. This revolution has meant a strong increase in the number of breweries currently out there. Without elaborating too much, let the following graphs speak for themselves – one describing the number of breweries in the US since 1873 and the other in the Netherlands since 1350 (only in Dutch). With the growing popularity of craft beers also comes an increasing interest in seasonality. This seasonality has value from both a supply-side and a demand-side point of view. For brewers it can have strategic value¹³. The continuous introduction of new beers as a result of a seasonal product strategy can keep consumer interest high over the year. An example is the ‘Dogfish Head’ brewery, which brews 5 major brands but also 18 seasonal brands, each sufficiently distinct from one another. Each of the seasonal beers is only available for two specific months. The seasonal beers bring opportunities for connecting with seasonal events, and also their limited availability can work positively: “Strangely, the “loss” of the chance to buy it tends to increase brand retention and intention to purchase.”¹³ From the consumers’ point of view, the seasonality of craft beers can bring unique qualities to the ‘beer experience’. The coming and going of seasonal beers brings continuous novelty, eliciting curiosity to ‘try something new’. Also the limited availability of seasonal craft beers may increase their perceived value – knowing that the very special ‘pumpkin ale’ that you bought is a limited edition might make you savor your ownership of it and the moment you drink it even more. I can imagine a similar experience may occur as with seasonal vegetables and fruits, which is an experience of a more cyclical nature: each year, we have a brief period in which we get to enjoy, for example, asperges or a particular apple cultivar (e.g., Elstar is my favorite). Besides enjoying these temporary treats, their limited availability also brings a sense of anticipation. Can seasonal beers, or any ‘seasonal processed food’ for that matter, offer a similar experience? If so, this allows us to consider seasonality not only as something relevant in terms of environmental sustainability or health, but also in terms of its potential to elicit rich experiences. In this post many questions still remain open that might be of interest for this blog: For example, what makes these seasonal craft beers actually seasonal? Is it because the flavours are specifically attuned to the seasons in a similar way that herfstbok and lentebok are promoted? Or do some brewers choose their ingredients based on what is actually seasonally available? Or are their techniques of brewing somehow seasonally dependent? And besides the potential rich experience of seasonal beers described above: what are additional reasons to choose a seasonal craft beer? Are they a form of supporting a local economy? Does the small scale production and seasonality of seasonal craft beers tell us anything about their environmental sustainability?  Is the rich diversity that these smaller brewers represent something valuable in its own right? References

1. Nelson, M. (2005). The barbarian’s beverage: a history of beer in ancient Europe. Routledge.
2. Unger, R. W. (2004). Beer in the Middle Ages and the Renaissance. University of Pennsylvania Press.
3. Nelsen (2005) writes: “The picture sketched so far seems to contradict the theory that already in prehistoric times there were two general drinking traditions in Europe, a wine-drinking tradition in the south and a beer-drinking tradition in the north, as attested much later. This seems far too simplistic. Rather in both areas there was, no doubt, an ancient tradition of making and drinking fermented beverages, but the only thing ostensibly determining what was used in these beverages seems to have been the availability of fermentable products.”
4. Weaver, J. C. (1944). United States malting barley production. Annals of the Association of American Geographers, 34(2), 97-131.
5. Oser, H. H. (2015). Producing quality barley for the malting industry. PhD thesis. The University of Nebraska-Lincoln.
6. Pržulj, N., Dragović, S., Malešević, M. et al. (1998) Comparative performance of winter and spring malting barleys in semiarid growing conditions. Euphytica 101, 377–382. https://doi.org/10.1023/A:1018388430317
7. https://www.gulpener.nl/gevolgen-tegenvallende-gerstoogst-2016/
8. Silm, S., & Ahas, R. (2005). Seasonality of alcohol-related phenomena in Estonia. International Journal of Biometeorology, 49(4), 215-223.
9. Lovett, C. K. (1977). A study of beer consumption trends in Montana.
10. Tremblay, P. F., Graham, K., Wells, S., Harris, R., Pulford, R., & Roberts, S. E. (2010). When do first-year college students drink most during the academic year? An internet-based study of daily and weekly drinking. Journal of American College Health, 58(5), 401-411.
11. Flissebaalje (2013) Bokbier in the Netherlands: a historical overview. Brewery History 152, 33-42
12. https://www.gall.nl/ontdek/bier/lentebok/#:~:text=Herfstbok%20is%20de%20tegenhanger%20van,Vandaar%20de%20naam%20’herfstbok’.
13. Pitta, D. A., & Scherr, B. G. (2009). The product strategy for seasonal products. Journal of Product & Brand Management.
14. Fay JC, Liu P, Ong GT, Dunham MJ, Cromie GA, et al. (2019) A polyploid admixed origin of beer yeasts derived from European and Asian wine populations. PLOS Biology 17(3): e3000147. https://doi.org/10.1371/journal.pbio.3000147