Evaluation of food flovor using semiconductor gas sensing system

人类嗅觉系统可以同时检测各种风味特性。嗅觉的模拟尚未建立。在这项研究中，一些半导体气体传感器的有用性，客观地识别食品风味作为一种流行的识别技术进行了研究。各种茶和大豆被用作本研究的食物样品。利用半导体气敏元件的电阻变化放大并记录的气敏系统，通过模式识别对混合香味气体进行识别。在本研究的开始阶段，数据是人工记录的，而在研究的最后一个学期，气体传感器的响应被自动输入个人计算机并进行统计分析，通过感官测试、基于化学挥发性成分的聚类分析和传感器的响应，对红茶、乌龙茶和绿色茶的9个样品的香气性质进行主观和客观评价，分类和鉴别。茶叶挥发性成分的模式识别分析与感官鉴定结果一致，两种方法都能很好地区分不同品种的茶叶。另一方面，传感器的响应不能清楚地区分每种茶，但它们可以区分红茶、乌龙茶和绿色茶;在大豆的情况下，化学分析和传感器的响应都可以很好地区分正常大豆、脂氧合酶（LO）2和3缺陷系以及LO 1，2，3缺陷系。实验结果与感官测试结果相吻合，表明该传感系统能够在一定程度上客观评价食品的味道特性。

The human olfaction system can simultaneously detect various flavor properties. The mimic of the olfaction have not yet been established. In this study, the usefulness of some semiconductor gas sensors to recognize food flavor objectively as a popular recognizing technique was investigated. Various kinds of teas and soy beans were used as the food samples for this study. A gas sensing system in which changes in the resistance on semiconductor gas sensors were amplified and recorded was used to discriminate flavor gas mixtures by pattern recognition. In the beginning of this study, the data was recorded manually, but in the last study term, the responses of the gas sensors were automatically taken into personal computer and subjected to statistical analyzes.Subjective and objective evaluation of aroma properties, classification and discrimination of nine tea samples of black, oolong and green tea by sensory test, cluster analyzes based on chemical volatile composition and the responses of sensors. Pattern recognition analysis of volatile composition of teas was consistent with sensory test, and both methods discriminated each tea including cultivated species very well. On the other hand, the responses of sensors could not discriminate each tea clearly, though they distinguished among black, oolong and green tea.In the case of soy beans, both of chemical analyzes and the responses of sensors discriminated among normal soy beans, lipoxigenase (LO) 2 and 3-deficient lines and LO 1,2,3-deficient lines, very well. In addition, those results corresponded the results of sensory test.By the application of the sensing system assembled in this study, it was showed that taste properties of food could be evaluated objectively to some extent.