从料液比、碱用量和无水乙醇用量方面进行单因素试验，并选用一次回归正交设计法对酸碱沉淀法分离啤酒花浸膏中α-酸和β-酸的工艺参数进行优化筛选。结果表明：分离β-酸的最优参数为KOH质量分数6.5%，无水乙醇用量1mL/g，料液比1：60(g/mL)，主次因素顺序为碱用量＞料液比＞无水乙醇用量；用全回归法求得的多元回归方程式为=84.375－2.843X1－1.995X2＋2.360X3。分离α-酸的最优参数组合为KOH质量分数8.5%，无水乙醇用量1mL/g，料液比1：60(g/mL)，主次因素顺序为无水乙醇用量＞料液比＞碱用量；用全回归法求得的多元回归方程式为：=82.667+1.515X1－2.950X2＋2.037X3。经高效液相色谱法检测，分离产品α-酸纯度达到86.43%，β-酸纯度达到87.12%，证明该分离工艺纯化效果良好。%This work reports the use of one-factor-at-a-time combined with linear orthogonal regression design to optimize process parameters including alkali (KOH) dosage (X1), anhydrous alcohol dosage (X2) and solid-to-solvent ratio (X3) for the extraction of humulone and lupulone from hop extract by acid-alkali precipitation. The optimal conditions for separating lupulone from hop extract were determined as 6.5% (m/m) of KOH dosage, 1 mL/g of anhydrous alcohol dosage and 1:60 g/mL of solid-to-solvent ratio. KOH dosage was the most important process condition followed by solid-to-solvent ratio and anhydrous alcohol dosage. The folowing multiple regression model that describes final lupulone content (Y) of the lupulone extract (i.e., purity) as a function of the process conditions was established by complete regression analysis:= 84.375- 2.843X1-1.995X2 + 2.360X3. The optimal conditions for separating humulone from hop extract were determined as 8.5% (m/m) of KOH dosage, 1 mL/g of anhydrous alcohol dosage and 1:60 (g/mL) of solid-to-solvent ratio. Anhydrous alcohol dosage was the most important process condition, solid-to-solvent ratio was in the middle and KOH dosage was the least important one. The folowing multiple regression model that describes final lupulone content (Y) of final humulone content (Y) of the humulone extract (i.e., purity) as a function of the process conditions was established by complete regression analysis:= 82.667 + 1.515X1-2.950X2 + 2.037X3. The purities of humulone and lupulone in both extracts were as high as 86.43% and 87.12%, respectively as shown by HPLC analysis.
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