Department of Food Science & Technology , Oregon State University , 100 Wiegand Hall , Corvallis , Oregon 97331 , United States.
Department of Statistics , Oregon State University , 239 Weniger Hall , Corvallis , Oregon 97331 , United States.
J Agric Food Chem. 2018 Apr 4;66(13):3505-3513. doi: 10.1021/acs.jafc.7b05784. Epub 2018 Mar 21.
The range of different nonvolatile constituents extracted from hops in highly hopped beers suggests that isohumulones may not be the sole contributor to beers' bitterness. Among brewers producing hop-forward beer styles, there is concern that the bitterness unit (BU) is no longer an accurate predictor of beer bitterness. This study examined factors within the beer matrix that influence sensory bitterness perception in highly hopped beers. Over 120 commercial beers were evaluated using sensory and instrumental techniques. Chemical analysis consisted of the BU via spectrophotometry, hop acids via high-performance liquid chromatography, total polyphenols via spectrophotometry, and alcohol content plus real extract via an Alcolyzer. Sensory analysis was conducted over two studies, and the beers' overall bitterness intensities were rated using a 0-20 scale. This study identified that the BU measurement predicts sensory bitterness with a nonlinear response, and it proposed an alternative approach to predicting bitterness based on isohumulones, humulinones, and ethanol concentrations. The study also revealed the importance of oxidized hop acids, humulinones, as a significant contributor to beer bitterness intensity.
从高苦值啤酒中提取的不同非挥发性成分的范围表明，异律草酮可能不是啤酒苦味的唯一贡献者。在生产高酒花啤酒风格的酿酒商中，人们担心苦味单位（BU）不再是啤酒苦味的准确预测指标。本研究考察了啤酒基质内的因素，这些因素影响高酒花啤酒的感官苦味感知。使用感官和仪器技术评估了 120 多种商业啤酒。化学分析包括分光光度法测定 BU、高效液相色谱法测定酒花酸、分光光度法测定总多酚以及 Alcolyzer 测定酒精含量和实际提取物。感官分析分两个研究进行，使用 0-20 标度对啤酒的整体苦味强度进行评分。本研究表明，BU 测量对感官苦味的预测呈非线性响应，并提出了一种基于异律草酮、胡芦巴酮和乙醇浓度预测苦味的替代方法。该研究还揭示了氧化酒花酸、胡芦巴酮作为啤酒苦味强度的重要贡献者的重要性。
