烤烟游离氨基酸与感官品质的关联及烘烤过程的变化规律研究

Correlation between free amino acids and smoking quality of flue-cured tobacco and variations during flue-curing process

为明确烤烟游离氨基酸与感官品质的关联性及烘烤过程的变化规律,连续2年制备了我国3类香型6个产区335份不同质量特征烟叶样品,系统研究了游离氨基酸与感官品质的相关性,并跟踪分析了烘烤过程游离氨基酸含量和组成的变化。结果表明:(1)烟叶游离氨基酸含量与感官品质总体呈负相关,碱性、芳香族和γ-ABA等氨基酸的关联规律在不同产区、年份表现稳定。(2)Lys、Phe等多数游离氨基酸含量在烘烤过程存在先上升后下降的变化趋势,碱性、芳香族氨基酸和γ-ABA在烘烤中后期的相对下降趋势强于其他种类氨基酸。(3)结合品质关联和烘烤过程变化分析结果,游离氨基酸与烟叶感官品质的稳定负关联规律可能与烘烤过程参与美拉德反应有关。游离氨基酸指标在烤后烟叶品质评价中具有较好应用前景,烘烤过程针对性降低游离氨基酸含量有利于烤后烟叶感官品质提升。

In order to study correlation between free amino acids and smoking quality of flue-cured tobacco leaves and the variation rule of free amino acids during flue-curing process,335 tobacco leaf samples of different quality characteristics from 6 typical flavor planting areas of China were prepared,and the relationship between concentration of free amino acids and smoking quality scores of flue-cured tobacco was investigated,and the variation of the concentration as well as composition of free amino acids during flue-curing process was analyzed.Results showed that:①There was a negative correlation between free amino acids concentration and smoking quality of flue-cured tobacco overall,especially for the basic amino acids,aromatic amino acids andγ-ABA,which presented a stable correlation law regardless of the planting area and different sampling year.②The majority of free amino acids concentration in tobacco leaves showed an upward and then downward trend in the curing process,and the relatively decline of basic,aromatic amino acids andγ-ABA during middle and late period of flue-curing was stronger than other kinds of amino acids.③Combined with the results of smoking quality related analysis and flue-curing process variation,the strong and stable negative correlation rule between free amino acid and smoking quality of tobacco leaves could result from the Maillard reaction during flue-curing.The index of free amino acids has a good application prospect in the evaluation of flue-cured tobacco quality and targeted reduced content of free amino acids in flue-curing process is beneficial for the smoking quality improvement of flue-cured tobacco leaves.