花椒麻度分级的改良斯科维尔指数法建立研究

A New Scoville Heat Unit(SHU) Method to Grade the Pungency Intensity of Dry Zanthoxylum bungeanum

针对辣椒辣度的斯科维尔指数(Scoville heat units,SHU)法存在对基质影响因素的忽略及检验结果缺乏统计学依据的问题,通过将单样品评价改为样品液与制备基质对照液的成对比较检验,以及增加评价小组人数或评价轮次改进实验设计等,建立了与辣味同为三叉神经感的花椒麻味感觉强度的间接测量方法——改良SHU法。应用新方法对花椒(Zanthoxylum bungeanum Maxim.)麻度进行测量与分级,并同时采用紫外分光光度计法对花椒中的酰胺含量进行了测定。结果表明:麻味感觉强度值与花椒酰胺的物理含量之间具有一定的一致性,但对某些品种而言,相近的或者较低的花椒酰胺含量表现出更强的麻感,较高的酰胺含量却能表现出较低的麻感。说明,花椒麻味感觉强度不仅与其所含的花椒酰胺总含量相关,也与花椒酰胺的构成及其结构相关。该方法的建立对花椒麻度相关研究以及应用麻度作为核心指标进行花椒及其制品质量评价与控制具有重要的理论和实践意义。

By taking into account existing problems such as the neglect of matrix effect and the lack of statistical basis for the judgments of Scoville heat unit(SHU) method, which is commonly used to determine the pungency degree of hot pepper, an improved SHU method was developed to evaluate the pungency intensity of Zanthoxylum bungeanum in this paper. The new SHU method used the paired comparison and increased the number of assessors in sensory panel or evaluation sessions. By applying the new method, the pungency intensity of Zanthoxylum bungeanum was evaluated and graded. Meanwhile, the amide content of Zanthoxylum bungeanum was determined by using UV spectrophotometry. The results showed that there existed a relative consistency between the pungency intensity of Zanthoxylum bungeanum and its amide content. However, some varieties of Zanthoxylum bungeanum with similar or lower amide content could have stronger pungency intensity, and the opposite results were observed for those with higher, suggesting that the pungency intensity of Zanthoxylum bungeanum is correlated with not only total amide content but also the compositions and structures of amide compounds. The modified SHU method is of great theoretical and practical significance for the research of pungency intensity evaluation and quality control of Zanthoxylum bungeanum and the development of its related products.