Saison

In the oldest sources saison is a keeping beer. A dictionary from Liège from 1823 describes it as an Advent or March beer that can be kept. Brewing manuals from the 19th century describe it as a beer that was brewed in winter and drunk after a few months. In 19th-century sources from Hainaut, 'de saison' after a beer name meant the version that was brewed in winter to be kept for about half a year.

The historian Roel Mulder, who laid these sources side by side, concludes that saison owes its name to the season in which it was brewed. Yvan De Baets, too, who defends the farmhouse story, describes saison as a beer that was brewed at the beginning of winter, and Lars Marius Garshol speaks of a seasonal beer.

A derivation from 'saisonniers' (seasonal workers) appears in none of these sources. De Baets does mention seasonal workers as possible drinkers of beer brewed on farms, but not as an explanation of the name.

What is established: the oldest sources, from 1823, describe saison as a keeping beer of professional brewers, mainly in the industrial city of Liège and later also in Hainaut. According to the historian Roel Mulder there is no historical text that describes saison as a typical countryside beer or as a beer for farm labourers. The oldest mention of the farmhouse story that he found is in a book from 1989 by Achille Latour, who based himself on conversations at the Dupont brewery.

The brewer Yvan De Baets worked the story out in 2004 in the book 'Farmhouse Ales' by Phil Markowski, which for many brewers and drinkers determined what saison is. He gave no source for it there, and according to Mulder he sometimes quotes old brewing books incorrectly. De Baets responded that he spoke to at least seven old saison brewers who all described an origin on the farm.

Lars Marius Garshol, who specialises in farmhouse brewing, points out that brewing beer for heavy field work was common all over Europe, for example in Denmark and Westphalia. He therefore finds it likely that De Baets is right, but acknowledges that direct evidence is lacking. Mulder, too, considers it likely that around Dupont in the early 20th century saison was sold to farmers.

Conclusion: an origin on the farm is possible, but has not been demonstrated. The BJCP also repeats the story, without a source.

The BJCP calls herbs and spices in saison 'uncommon, but allowable if they don't dominate': unusual, but permitted as long as they do not dominate.

The spicy, often peppery note comes mainly from the saison yeast; the hops can be spicy too. The BJCP speaks of a fruity-spicy, sometimes phenolic yeast profile. Saison is usually fermented with diastatic yeasts, and according to yeast research these make the spicy, phenolic aroma compound 4-vinylguaiacol. That is the same compound that gives the clove note in weizen. Still, the BJCP usually describes the spiciness of saison as peppery, not as clove. In saison that compound belongs to the style, whereas in many other beers it counts as a fault. In witbier it is the other way round: there, citrus and spiciness come mainly from added coriander and orange peel.

On the historical use of spices such as star anise, sage or coriander in saison, Yvan De Baets, according to Roel Mulder, gave no sources. Whether old saisons were spiced has therefore not been demonstrated.

IBU (International Bitterness Units) is, according to CraftBeer.com, a measure of the bitter compounds in beer, determined in the lab as milligrams of iso-alpha acids (converted bitter compounds from hops) per litre. The Brewers Association writes in its style guidelines that this figure measures one specific hop compound and does not consistently match how bitter someone perceives the beer. It gives three reasons for that: sensitivity to bitterness differs per person (partly through genetic make-up), other ingredients also contribute to bitterness, and hop aroma and flavour can strongly change the perceived bitterness.

The guidelines themselves give examples. For Export-Style Stout the BA writes that the bitterness can turn out high in the lab, but that the sweetness of the malt dampens the perception. Conversely the BJCP says of kölsch that drier versions can seem hoppier or more bitter than the IBU suggests. And in hazy IPA the bitterness is, according to the BJCP, often masked by the fuller body and the soft finish.

For orientation: CraftBeer.com gives 5–10 IBU for light lagers and 50–70 for robust, bitter IPAs. So use IBU as a rough indication, not as a flavour promise.