A Fishy Business

When it comes to beer, the received wisdom in this country is that crystal clear is good but cloudy is bad. I’ve seen plenty of drinkers hold their pint up to the light and take it back to the bar if it’s a bit hazy.
There are plenty of excellent beers in Belgium and Germany that are intended to be cloudy. So when did our obsession with clarity begin, and what has a fish product to do with it?
When beer was served in pewter tankards, its appearance was not particularly important. However, with the introduction of mass-produced glassware in the early 20th century and improved lighting in pubs, the clarity of beer became an important selling point. And when, in the middle of the century, cask-conditioned ale was in decline, cloudy beer was often (correctly) attributed to the dregs at the bottom of the barrel.
When beer has completed its fermentation, it contains yeast cells in suspension and this gives a hazy appearance. If the beer is left long enough it will settle naturally but, in a commercial setting, there is a need to speed up the process.
With beer destined for kegs, the big brewers use industrial-scale filters and centrifuges. However, for cask-conditioned beers, brewers add substances known as finings. These attract the yeast cells and form clumps that sink to the bottom of the cask more quickly.
Over the years, a variety of substances have been used as finings, including oyster shells, seaweed and silica. But the most common is called isinglass, a product refined from fish swim bladders. Traditionally, these were from sturgeon but, these days, the swim bladders are sourced from fish caught in tropical and subtropical rivers.
It is accepted that isinglass is a processing aid and is not consumed with the beer. However, as it is derived from fish, many drinkers, including vegans, are unhappy with its use in brewing.
As a result, a number of brewers are producing unfined beer that is slightly cloudy. At Moor Beer in Bristol, Justin Hawke champions “natural” beer. He believes that isinglass strips some of the flavour from beer. Another brewery whose beers are all unfined and unfiltered is the award-winning Brass Castle in Malton, North Yorkshire. More locally, Nottingham’s Castle Rock is producing a series of experimental, unfined beers badged as Traffic Street Specials.
As unfined beers become more common, it is important that bar staff are trained to explain to drinkers that the beer they have asked for may appear hazy. Otherwise, they could have numerous disgruntled customers returning their pints or leaving the pub in disgust!
And what about the beer? Traffic Street Special #6 Rat Race (4.7% ABV) is a rich, ruby ale with a fruit flavour and biscuity sweetness. It may have been unfined but it tasted fine.

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