响应面法优化结晶麦芽制备工艺

Optimization of Preparation Technology of Crystallized Malt byResponse Surface Methodology

为提高结晶麦芽品质及结晶率,本研究通过单因素和响应面试验优化结晶麦芽制备中预糖化和焙焦工艺,分别以游离氨基氮含量和还原糖含量为指标研究预糖化工艺对结晶麦芽的影响,同时以水分含量、结晶率和色度为指标优化焙焦工艺。结果表明:选择发芽时间为72 h的绿麦芽,在45℃下进行蛋白质休止1.5 h,在pH=6.0、温度为66.4℃下进行糖化2.0 h,此条件下的还原糖含量最高,糖化效果最佳;进一步在127℃下焙焦27 min,制得水分含量为3.75%、色度为(158.9±1.19)EBC、结晶率高达99%的结晶麦芽。与市售结晶麦芽相比,该结晶麦芽内部能够完全结晶,结晶品质较高,其他质量指标也得到明显优化。

In order to improve the quality and crystallization rate of crystalline malt, this study optimized the presaccharification and kilning processes in the preparation of crystalline malt through single factor and response surface experiments. The free amino nitrogen content and reducing sugar content were used as indices to study the effect of presaccharification process on crystalline malt. At the same time, the coking process was optimized with moisture content,crystallization rate and color as indices. The results showed that the green malt with a germination time of 72 h was selected, the protein was rested at 45 ℃ for 1.5 h, and the saccharification was carried out at pH = 6.0 and temperature of66.4 ℃ for 2.0 h. Under these conditions, the reducing sugar content was the highest and the saccharification effect was the best. Further the malt was baked at 127℃ for 27 min to obtain a crystalline malt with a moisture content of 3.75%, a chromaticity of(158.9±1.19) EBC, and a crystallization rate of 99%. Compared with commercially available crystalline malt, the crystalline malt can be completely crystallized inside, the crystalline quality is better, and other quality indicators have been significantly optimized.