开放光程FTIR光谱的葡萄品质劣变监测方法

前期的研究报道了红外光谱能够监测水果变质产生的挥发物质，其方法是将挥发物收集在气室中，利用多次反射的结构来增强光信号。实验中，我们使用开放光程傅里叶变换红外光谱法监测葡萄变质挥发物，尝试了主动和被动两种测量模式。根据红外光谱特征对葡萄品劣变过程中产生的挥发物进行了定性分析，并在研究中测量了葡萄储藏期间挥发物质的红外光谱特征的强度变化，并且根据这种变化规律建立了不同变质阶段的分类方法。此外，还尝试直接从原始光谱中分析挥发物质，证明了挥发物在原始光谱上仍然具有明显的光谱特征。这一研究证实了现场开放式傅里叶变换红外光谱法监测水果变质的可行性。开放光程傅里叶变换红外光谱法所具有的灵活使用性和非接触式在线测量的优点，使其有可能应用于大面积监测储藏中的水果变质问题，并具有进一步定位劣变源的潜力。

Monitoring of Grape Decay via Its Volatiles Based on Open-Path Fourier Transform Infrared Spectroscopy

We had testified that the decay volatile of fruit could be detected by using infrared spectroscopy. We collected volatile to a gas cell in this methods and used multi-reflecting structure to enhance optical path. In this study, we used open-path infrared spectroscopy to monitor grape decay volatiles and tried both active and passive modes. We qualitatively analyzed the volatiles produced by the decay grape according to the characteristics of infrared spectroscopy, and measured the infrared spectra of the volatiles during storage establishing the method for different decay status according to the changing rules. We also tried to directly analyze the volatile by the origin spectra and demonstrated that it still had obvious spectra characteristics. In this study, It was proved to be feasible using open-path infrared spectroscopy to monitor the decay volatiles. With the advantages of flexible use and non-contact on-line measurement, the method could be applied in large area to monitor the decay status of fruit and even to locate decay source.