Abstract This study was conducted to identify which traits or combination of traits associated with malting quality and mashing performance could best define the differences between and within a population of six pre-Prohibition malting barley varieties and a population of five modern elite malting barley cultivars. To accomplish this, standard and nonstandard metrics of malt quality and of performance during Congress mashing were analyzed by simple linear correlations and multivariate statistics. Analyses of the two populations combined revealed that activities of α-amylase at each time sampled during mashing were positively and significantly correlated with the concentrations of glucose at that same time, were not significantly correlated with maltose concentrations at any time, and were only significantly correlated with maltotriose concentrations for the first 30 min of mashing. Activities of β-amylase were not significantly correlated with concentrations of glucose, maltose, or maltotriose at any time during mashing. Analysis of α-glucosidase activities showed no consistent trends in correlations with either glucose or maltotriose and no significant correlation with maltose at any time. Analysis of limit dextrinase activities showed significant and positive correlations with glucose and maltotriose concentrations prior to the mash temperature reaching the starch conversion stage. Although no individual amylolytic enzyme activity was significantly correlated with maltose concentration, diastatic power was positively and significantly correlated with maltose at five of six times sampled during mashing. Diastatic power was not significantly correlated with glucose or maltotriose concentrations at any time. Malt extract values and osmolyte concentrations were positively and significantly correlated with mash glucose concentrations at all times sampled, with maltose concentrations at the first four times sampled, and with maltotriose for the first five times. Principal component analysis (PCA) of the traits analyzed in the two populations combined showed that the modern malting barleys were generally well separated from the pre-Prohibition barleys by three principal components that accounted for 75% of the variation among the 11 cultivars. The traits that collectively contributed the most to separation of the modern from the pre-Prohibition barleys were osmolyte concentrations, malt extract values and glucose concentration, which were higher in the modern cultivars, and α-glucosidase thermostability and concentrations of maltopentaose, maltohexaose and maltoheptaose, which were higher in the pre-Prohibition cultivars. PCA of the individual populations also separated Tradition from the other modern cultivars due to its lower levels of glucose, maltotriose, and α-amylase activity and by its higher levels of maltose and % plump. PCA of the pre-Prohibition population separated Hanna from the other pre-Prohibition cultivars primarily by its higher levels of maltopentaose through maltoheptaose and its low levels of osmolytes. Silver King was somewhat displaced from other pre-Prohibition cultivars due to its low levels of osmolytes and to its very high levels of α-glucosidase thermostability.

中文翻译：

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现代美国和加拿大麦芽大麦品种与禁令前的品种的比较：IV。使用标准和非标准措施进行麦芽质量评估

摘要 本研究旨在确定与麦芽质量和糖化性能相关的哪些性状或性状组合可以最好地定义六个禁酒前麦芽大麦品种群体和五个现代优良麦芽大麦品种群体之间和内部的差异。为了实现这一点，通过简单的线性相关性和多变量统计分析了麦芽质量和国会糖化期间性能的标准和非标准指标。对两个群体进行组合分析表明，在糖化过程中每次采样的α-淀粉酶活性与同一时间的葡萄糖浓度呈显着正相关，与任何时间的麦芽糖浓度均不显着相关，并且仅与糖化前 30 分钟的麦芽三糖浓度显着相关。在糖化过程中的任何时间，β-淀粉酶的活性与葡萄糖、麦芽糖或麦芽三糖的浓度没有显着相关性。α-葡萄糖苷酶活性的分析显示与葡萄糖或麦芽三糖的相关性没有一致的趋势，并且在任何时候与麦芽糖没有显着的相关性。极限糊精酶活性分析表明，在醪液温度达到淀粉转化阶段之前，葡萄糖和麦芽三糖浓度呈显着正相关。尽管没有单个淀粉分解酶活性与麦芽糖浓度显着相关，但在糖化过程中采样的六次中的五次中，糖化能力与麦芽糖呈正相关且显着相关。在任何时候，糖化能力与葡萄糖或麦芽三糖浓度均无显着相关性。麦芽提取物值和渗透物浓度与所有采样时间的麦芽糖浓度、前四次采样时的麦芽糖浓度和前五次采样时的麦芽三糖浓度均呈显着正相关。对两个群体中分析的性状进行主成分分析 (PCA) 表明，现代麦芽大麦与禁酒令前的大麦通常通过三个主成分很好地分离，这三个主成分占 11 个品种之间变异的 75%。对现代大麦与禁酒前大麦的分离贡献最大的特征是渗透物浓度、麦芽提取物值和葡萄糖浓度，在现代栽培品种中较高，α-葡萄糖苷酶的热稳定性和麦芽五糖、麦芽六糖和麦芽七糖的浓度在禁酒前栽培品种中较高。由于其较低水平的葡萄糖、麦芽三糖和 α-淀粉酶活性以及较高水平的麦芽糖和丰满度，个体种群的 PCA 也将 Tradition 与其他现代栽培品种区分开来。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。α-葡萄糖苷酶的热稳定性和麦芽五糖、麦芽六糖和麦芽七糖的浓度，在禁酒令前的品种中更高。由于其较低水平的葡萄糖、麦芽三糖和 α-淀粉酶活性以及较高水平的麦芽糖和丰满度，个体种群的 PCA 也将 Tradition 与其他现代栽培品种区分开来。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。α-葡萄糖苷酶的热稳定性和麦芽五糖、麦芽六糖和麦芽七糖的浓度，在禁酒令前的品种中更高。由于其较低水平的葡萄糖、麦芽三糖和 α-淀粉酶活性以及较高水平的麦芽糖和丰满度，个体种群的 PCA 也将 Tradition 与其他现代栽培品种区分开来。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。由于其较低水平的葡萄糖、麦芽三糖和 α-淀粉酶活性以及较高水平的麦芽糖和丰满度，个体种群的 PCA 也将 Tradition 与其他现代栽培品种区分开来。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。由于其较低水平的葡萄糖、麦芽三糖和 α-淀粉酶活性以及较高水平的麦芽糖和丰满度，个体种群的 PCA 也将 Tradition 与其他现代栽培品种区分开来。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。禁酒令前种群的 PCA 将 Hanna 与其他禁酒令前的栽培品种区分开来，主要是因为它的麦芽五糖至麦芽七糖水平较高，并且渗透物水平较低。由于其渗透物水平低和α-葡萄糖苷酶热稳定性水平非常高，Silver King 在某种程度上被其他禁酒令前的品种所取代。