Perceptions of Foam
Chapter
I turned up to give my paper on beer foam at the American Society of Brewing Chemists (ASBC) annual meeting in Tucson 20-odd years ago. On the first slide (no PowerPoint in those days) I included the sentence “Foam is a critical component of beer quality.” Yet all the beer I consumed that week came directly from cans slid into sleeves that boasted the name of the hotel. No foam was in evidence for the entire conference, although lots of excellent beer was enjoyed. The question is begged, then, just how important foam really is. I believe the answer to be “very, but only when the beer is seen.” In other words, there are two modes of drinking, which we might call the informal (straight from the can or bottle) and the formal (with the beer poured into a glass). Despite my frequent protestations that the only civilized way to sip beer is from a glass, I am prepared to admit that there are drinking occasions when the informal approach is relevant— when fishing, for example.* What do people make of foam, though? Is it important? We have performed several studies that suggest it is, indeed, very important. We took photographs of a well-known U.S. lager that had been poured and drained in various ways in order to present different foaming patterns. The beers (Fig. 1-1) were arranged in various sequences to * I don’t fish.
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Chapter 1 Perceptions of Foam
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Chapter 1 Perceptions of Foam
Fig. 1-1. Perceptions of foam experiment 1. Reproduced, by permission, from Bamforth (2000).
represent different foam qualities at the beginning, middle, and end of drinking. The very fact that we could produce such a range of foam appearances from a single beer is testimony to the criticality of the pour. We showed the photographs to people in Davis, California, but also to people in Hull, Oxford, and Sheffield in England, Tokyo in Japan, and Nuremberg in Germany. 3
Chapter 1 Perceptions of Foam
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Despite the frequent assertion that foam is of limited importance in the United States, it was clear that the presence of a head certainly did meet with favor here, just as in all other locations surveyed. However, it seems that those people who normally drink beer from a glass better appreciate the lacing. Some people feel that lacing is evidence of a clean glass and of a beer that is not flat, whereas others believe that cling is dirty and unappealing. So there is a split between those who want to see lacing on an emptied glass and those who want to see a totally “clean” glass when they have finished. Most consumers seem to view excessive initial foaming with disfavor. Beers with “respectable” amounts of foam at the start and good head retention were predicted to have better flavor. Various respondents commented that beers with better foams look colder. Overall, though, there were indications that men tended to appreciate foam more than women did. One of the criticisms of the work was that we used a beer that was 100% bittered with reduced iso-α-acids, material that tends to produce very stiff foams. Perhaps (we were challenged) this stiffness was what some people did not like in the lacing patterns. In two subsequent studies, we furthered this approach, this time with a beer not bittered with light-resistant preparations. The first of these studies compared American and Scottish drinkers for their perceptions of the importance of foam. Americans, it seemed, did not want too much foam or lacing, but they did perceive beers with insufficient of either as being somehow less alcoholic. Conversely, beers with excessive foam and lacing were believed to come from a dirtier glass (although, of course, the opposite is true). The Scottish liked intermediate levels of foam and lacing: they felt the beers were better handled, better brewed, and would have better flavor and more drinkability. The moral from this study was “hit the middle ground.” In a subsequent assessment, we pondered the issue of what customers might hope to see throughout the drinking experience. What did they expect to observe when presented with a full glass of beer? What did they like midway through the drink? Finally, what did they expect to see left behind in the glass after drinking the beer? What we did with subjects in Belgium, Finland, Ireland, and Scotland was to show people three sets of photographs: one set with full glasses of
newly poured beer with different amounts of foam; one with the beer half drunk with different amounts of lacing on the glasses; and a third in which no beer remained but there were different amounts of cling. People were asked to select their preferred image from each of the three sets. The Belgians preferred a lot of foam at the start; of the four nations, the Scots opted for the least foam, with the Irish and Finns in-between. Generally, there was a preference for the foam to remain at a constant depth throughout drinking. However, for most nations (although not for the Belgians) preference was based on foam at the start rather than lacing alone or head and lace combinations: in other words, the starting appearance is the most important, with the residual foam and patterns of cling less important but not insignificant. A study in the Czech Republic (see the entry for Kosin et al in the reading list at the end of this book) suggested that drinkers in that country only pay heed to the foam when bald patches start to appear through the foam atop the beer. Finally, we have the matter of gender. Do men and women have different preferences when it comes to foam? Perhaps the work of Jeremy Roza (Fig. 1-2) would suggest yes. It seems that to a certain extent women view lacing less favorably than do men.
Chapter 1 Perceptions of Foam
Fig. 1-2. What men and women think about lacing. Reproduced, by permission, from Roza et al (2006).
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