Haze can have a significant impact on consumer perception of beer quality. Image Source: stock.tookapic.com
Creating the perfect beer is truly a craft. Both beer connoisseurs and casual drinkers alike often know exactly what they’re looking for in a beer and, just as importantly, what they’re not looking for. As such, breweries must take great care in creating beers that not only taste delicious but are appealing to the eye. One of the primary aesthetic concerns breweries face is haze, or turbidity, which interferes with the clarity of beers and can drastically affect consumer purchasing decisions as well as taste and quality perception.
Seeking Clarity
Haze is the scattering of light by fine particles that produces a clouding effect in transparent liquids. In beer, haze particles are typically the result of non-biological factors such as starches, lipids, proteins, polyphenols, and colloidal carbohydrates. At times, haze from these sources may only be apparent in cold conditions, a phenomenon known as “chill haze.” In other cases, haze is caused by biological components such as microorganisms, which can indicate contamination and is a non-reversible feature of the beer. Although haze has no inherent meaning—it may be a benign aesthetic quality, a predictor of shelf life, or a major indicator of spoilage—its presence is typically undesirable for consumers regardless of whether or not it impacts taste. As Professor Chengdao Li says, “Beer drinkers are becoming more sophisticated, they want a beer looking good, very clear with good colour and no haze.”1 Driven by this market demand, researchers have spent considerable time investigating how to eliminate haze through raw ingredient selection, beer formulation, and specific processing methods designed to eliminate cloudiness. Meanwhile, both the European Brewery Convention (EBC) and the American Society of Brewing Chemists (ASBC) have developed haze measurement standards to classify brews according to clarity.2
Spectrophotometric haze measurement can be a critical part of evaluating the impact of beer variables, such as wheat variety. Image Source: Pexels user Zugr