Abstract Malt is an essential ingredient in beer; not only because it provides yeast with essential nutrients such as amino acids and fermentable sugars, it also adds to the beer’s color, body and flavor. The objective of this project was to look at the initial concentration of total nitrogen (TN) found within base malts of different varietal and cultivar origins and its impact on the esters produced in beers made using these malts. The experimental beer was brewed with a target OG of 10° Plato wort using five different base malts; four of which were produced by independent craft maltsters (Texas, Oregon, Indiana, and Canada) and a macro-industrial produced malt served as the control. TN and free amino nitrogen (FAN) were analyzed and compared with volatile and semi-volatile flavor analysis in order to identify correlations between nitrogen concentration and ester development within the final beer. One-way ANOVA coupled with a Tukey HSD paired comparison test was run to determine statistical differences in TN and FAN, while Kruskal-Wallis one-way analysis of variance test was utilized to determine statistical differences between total esters production. TN wort values ranged from 627 to 909 mg/L, while FAN wort values ranged from 191 to 467 mg FAN/L. There were statistical differences seen between all of the beers in total ester production. The beers produced with malts of higher TN resulted in greater ester production. From this, one can conclude that there is a correlation between a malt’s TN and esters produced in the final beer product.

中文翻译：

---

工艺麦芽中的氮含量：对啤酒中总酯浓度的影响

摘要 麦芽是啤酒中必不可少的成分；不仅因为它为酵母提供了必需的营养物质，如氨基酸和可发酵糖，它还增加了啤酒的颜色、酒体和风味。该项目的目的是研究在不同品种和栽培品种来源的基础麦芽中发现的总氮 (TN) 初始浓度及其对使用这些麦芽酿造的啤酒中产生的酯的影响。实验啤酒是用 10° 柏拉图麦芽汁的目标 OG 酿造的，使用五种不同的基础麦芽；其中四个由独立的手工麦芽制造商（德克萨斯州、俄勒冈州、印第安纳州和加拿大）生产，宏观工业生产的麦芽作为对照。分析了 TN 和游离氨基氮 (FAN)，并将其与挥发性和半挥发性风味分析进行比较，以确定最终啤酒中氮浓度与酯形成之间的相关性。运行单向方差分析与 Tukey HSD 配对比较测试以确定 TN 和 FAN 的统计差异，而 Kruskal-Wallis 单向方差分析测试用于确定总酯产量之间的统计差异。TN 麦汁值范围为 627 至 909 mg/L，而 FAN 麦汁值范围为 191 至 467 mg FAN/L。所有啤酒的酯总产量存在统计学差异。用更高 TN 的麦芽生产的啤酒会产生更多的酯。由此，