Different malt samples with various total acid content were used to brew beer.The organic acid content in both the malt and the brewed beer was measured by using high-Performance liquid chromatography(HPLC)to establish the correlation between the total acid content in malt and the organic acid content in the beer.Additionally,gas chromatography-mass spectrometry(GC-MS)was used to detect the components of volatile compounds in the beer,and sensory evaluation was employed to assess the brewed beer's qualities.The results indicated that as the total acid content in malt increased,the pH value gradually decreased,and the content of succinic acid,malic acid,lactic acid,and acetic acid increased.There was a significant positive correlation between the total acid content in malt and the total acid content,malic acid content,and lactic acid content in the beer,with correlation coefficients of 0.94,0.94,and 0.92,respectively.Different malt samples with varying total acid content demonstrated different characteristic aroma compounds in the brewed beer,contributing to differences in sensory attributes.As the total acid content in malt increased,the perceived acidity score of the brewed beer increased,while the scores for hop/fruit aroma,phenolic aroma,and alcohol perception decreased.

In order to study the quality change of coffee malt premixed powder with the extension of storage period, the coffee malt premixed powder was stored at the environment where the temperature is 25 ℃ and 35 ℃, respectively, and the relative humidity is 50% respectively. Its moisture, fatty acid value and falling value were monitored during the whole storage period. The volatile compounds were separated and identified by solid phase microextraction accompanying gas chromatography-mass spectrometry during the whole storage period. The results demonstrated that with the extension of storage period, the overall moisture content shows a falling trend, while the fatty acid value and falling value show an overall rising trend. The higher the storage temperature, the more significant the change is 41 kinds of main volatile compounds of coffee malt ready mixed powder were identified. It mainly includes 13 kinds of aldehydes, 15 kinds of heterocycles, 7 kinds of esters, 4 kinds of alcohols and 2 kinds of ketones. Among them, the relative concentration of aldehydes (n-hexanal, nonanal, trans-2-nonenal) showed an increasing trend with the extension of storage period.

特种麦芽是丰富啤酒品类必不可少的原料,其品类繁多却缺少统一的命名规则,给广大精酿啤酒生产者带来诸多困扰.该文总结了特种麦芽在啤酒酿造中提升啤酒色度、丰富香味、改善口感和优化糖化条件等方面的作用,进而分析了特种麦芽品质形成所涉及的主要化学反应——美拉德反应、焦糖化反应和裂解反应.提出了基于特种麦芽品质形成机理的特种麦芽分类系统,将特种麦芽划分为干燥类、焦香类、焙焦类、烘烤类和其他类并展望了特种麦芽的发展前景.该综述不仅可为特种麦芽新产品的研发提供理论指导,还可为啤酒酿造师选择特种麦芽产品提供科学依据.

There is a directly relationship between the oxidation rate and the endogenous oxidoreductases in the barley and malt.Changes of oxidoreductases in malting process were studied in this paper.The results showed that the oxidoreducatases were reduced by changing the malting process,which provided references for improving malting process of high anti-oxidation.

由于剥皮制粉工艺与传统制粉相比,具有基建和设备投资少,生产制造费用低,能更合理充分地利用小麦资源.因而现在逐渐被更多的人们所接受.其实剥皮制粉早在60年代我国就已应用,发展至今我国已有二百多家面粉厂应用了剥皮制粉工艺.剥皮制粉工艺在国外也有相当的发展,并且已形成了一个比较成熟的制粉工艺PerTec.