The quality of draught beer is important to consumers but can be inconsistent, ranging from excellent through to unacceptable. The few, dated studies of draught beer quality have focused on the number of microorganisms that are present in the product. Work reported here suggests that this approach has its limitations and fails to relate to beer quality post‐dispense. An alternative approach using the long‐established ‘forcing’ method provides a better but still retrospective assessment of draught beer quality. Samples post dispense are ‘forced’ by static incubation at 30°C for four days and beer quality is ranked by the measurement of absorbance at 660 nm. The increase in absorbance reflects the growth of beer spoilage microorganisms present in the beer at dispense. Four quality bands are proposed, where quality is described as excellent (absorbance increase of <0.3), acceptable (0.3–0.6), poor (0.6–0.9) and unacceptable (>0.9). The method is straightforward, requires no special skills and enables, for the first time, the robust quantification of draught beer quality. It is anticipated that the method will have widespread application in the measurement and improvement of the quality of draught beer. Copyright © 2017 The Institute of Brewing & Distilling

The quality of draught beer in 57 on-trade licensed premises in 10 locations in the UK Midlands was assessed using a forcing test. Of 149 samples of standard lager ('SL', abv ≤ 4.2%), 44% were in the 'excellent' quality band compared with 16% of 88 samples of keg ale ('KA', abv ≤ 4.2%). Of the total of 237 samples, >90% were represented by two lager and two ale national brands. There were differences in the quality index (QI) between the brands, with lager SL3 having a QI of 84% compared with 72% for lager SL6, 71% for ale KA5 and 68% for ale KA1. The susceptibility of the four brands to spoilage was assessed using a challenge test with microorganisms taken from forced draught beer samples of the brands. Ale KA5 (challenge test QI = 87.5%) was the most resistant to spoilage followed by lager SL3 (81.3%), lager SL6 (75%) and ale KA1 (62.5%). Keg beers in accounts with a national cask beer quality accreditation had the same QI as those without accreditation. Analysis of price vs quality showed that the most expensive price band had the lowest quality. Draught beer quality declined as the number of dispense taps increased across the bar. It was also noted that dispense into branded half-pint glasses had variable take-up, with lager SL3 served in the correct branded glassware on 71% of occasions but only on 5% of occasions for lager SL6. None of the keg ales were served in correctly branded glassware.