Acta Chimica Sinica ›› 2013, Vol. 71 ›› Issue (02): 234-238.DOI: 10.6023/A12110872 Previous Articles     Next Articles



王文重a,b, 董大明a, 郑文刚a, 韩峻峰b, 叶松b, 矫雷子a, 赵贤德a   

  1. a 北京市农林科学院 国家农业信息化工程技术研究中心 北京 100097;
    b 桂林电子科技大学电子工程与自动化学院 桂林 541004
  • 投稿日期:2012-11-05 发布日期:2012-12-28
  • 通讯作者: 董大明
  • 基金资助:

    项目受国家自然科学基金(No. 31101748, 31271614)和北京市农林科学院创新能力建设专项(No. KJCX201102001)资助.

Analysis of Volatiles during Grape Deterioration Using FTIR

Wang Wenzhonga,b, Dong Daminga, Zheng Wenganga, Han Junfengb, Ye Songb, Jiao Leizia, Zhao Xiandea   

  1. a National Engineering Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097;
    b School of Electronic Engineering and Automation, Guilin University of Electronic Technology, Guilin 541004
  • Received:2012-11-05 Published:2012-12-28
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Nos. 31101748, 31271614) and Innovation Building Program of Beijing Academy of Agriculture and Forestry Sciences (No. KJCX201102001).

Grape is very perishable in transportation and storage, so its early warning is particularly important to lower the risks of large-scale deterioration. In order to study grape deterioration process, we analyzed the volatile compounds from grapes using Fourier transform infrared (FTIR) spectroscopy. Several grapes were put in the sample compartment of the FTIR spectrometer for 2 h per day. Then, the volatile compounds vaporized from the grapes were measured directly using the spectrometer. A high energy ceramic IR-source was used to improve the signal-to-noise ratio. We collected the FTIR spectrum before sample was put in as a background to eliminate the influence of air. Spectral signatures of the volatiles from grapes were analyzed and used to classify the grape samples into deterioration or not. By spectral analysis, the volatile mainly includes ethyl acetate, ethanol and carbon dioxide. The above three volatile vaporized more and more from the grapes during deterioration process. We also found that the release rates of volatile compounds get its highest value when the grapes just started deteriorating, so, this value could be used to monitor the beginning of deterioration. The methods to classify grapes deterioration levels were also studied. Firstly, grape deterioration processes were divided into three stages, fresh, slight deterioration and severe deterioration, by appearance and sensory evaluation. Then, a principle compounds analysis (PCA) was used for unsupervised classification to FTIR spectra. Results showed that this method could distinguish grapes into fresh and deterioration by choosing proper data pre-processing algorithms. This paper provides a new way to study the fruit deterioration mechanism, and premise a foundation for developing early-warning equipment for evaluation and monitoring fruit deterioration during its storage and transportation. Furthermore, because of the step change of release rates of volatile compounds at the beginning of deterioration, this kind of classifying method and monitoring system may not influenced by grapes quantity and store patterns.

Key words: grape deterioration, volatile compounds, Fourier transform infrared (FTIR), principal component analysis (PCA), classification