Chinese vinegar classification via volatiles using long-optical-path infrared spectroscopy and chemometrics.

Different brands of Chinese vinegar are similar in appearance, color and aroma, making their discrimination difficult. The compositions and concentrations of the volatiles released from different vinegars vary by raw material and brewing process and thus offer a means to discriminate vinegars. In this study, we enhanced the detection sensitivity of the infrared spectrometer by extending its optical path. We measured the infrared spectra of the volatiles from 5 brands of Chinese vinegar and observed the spectral characteristics corresponding to alcohols, esters, acids, furfural, etc. Different brands of Chinese vinegar had obviously different infrared spectra and could be classified through chemometrics analysis. Furthermore, we established classification models and demonstrated their effectiveness for classifying different brands of vinegar. This study demonstrates that long-optical-path infrared spectroscopy has the ability to discriminate Chinese vinegars with the advantages that it is fast and non-destructive and eliminates the need for sampling.

[1]  P. Griffiths.  Fourier Transform Infrared Spectrometry , 2007 .

[2]  R. M. Hammaker,et al.  AN INTRODUCTION TO Open-Path FT-IR Atmospheric Monitoring. , 1994, Environmental science & technology.

[3]  Zou Xiaobo,et al.  The study of gas sensor array signal processing with new genetic algorithms , 2002 .

[4]  D. Feist,et al.  A new fully automated FTIR system for total column measurements of greenhouse gases , 2010 .

[5]  Z. Bacsik,et al.  Comparison of Open Path and Extractive Long‐Path FTIR Techniques in Detection of Air Pollutants , 2006 .

[6]  Peter R. Griffiths,et al.  Comprar Fourier Transform Infrared Spectrometry | James D. Winefordner | 9780471194040 | Wiley , 2007 .

[7]  L Palla,et al.  HS-SPME/GC–MS and chemometrics for the classification of Balsamic Vinegars of Modena of different maturation and ageing , 2011 .

[8]  N. Magan,et al.  Volatiles as an indicator of fungal activity and differentiation between species, and the potential use of electronic nose technology for early detection of grain spoilage. , 2000, Journal of stored products research.

[9]  Wang Aili,et al.  Key aroma compounds in Shanxi aged tartary buckwheat vinegar and changes during its thermal processing , 2012 .

[10]  Peter Fuchs,et al.  DFB Lasers Between 760 nm and 16 μm for Sensing Applications , 2010, Sensors.

[11]  Volker Ebert,et al.  In situ TDLAS measurement of absolute acetylene concentration profiles in a non-premixed laminar counter-flow flame , 2012, Applied Physics B.

[12]  C. Pizarro,et al.  Vinegar classification based on feature extraction and selection from headspace solid-phase microextraction/gas chromatography volatile analyses: a feasibility study. , 2008, Analytica chimica acta.

[13]  Hiroyuki Yamada,et al.  Real-time measurement of nitrogen dioxide in vehicle exhaust gas by mid-infrared cavity ring-down spectroscopy , 2011 .

[14]  Yan Li,et al.  MONITORING LEAKING GASES BY OP-FTIR REMOTE SENSING , 2002, Journal of environmental science and health. Part A, Toxic/hazardous substances & environmental engineering.

[15]  Roland Harig,et al.  Infrared remote sensing of hazardous vapours: surveillance of public areas during the FIFA Football World Cup 2006 , 2007, SPIE Defense + Commercial Sensing.

[16]  P. Gemperline.  Practical Guide To Chemometrics , 2006 .

[17]  Jiewen Zhao,et al.  Traditional Vinegars Identification by Colorimetric Sensor , 2012 .

[18]  T. Acree,et al.  Flavor science: sensible principles and techniques , 1993 .

[19]  L Jiao,et al.  A new volatiles-based differentiation method of Chinese spirits using longpath gas-phase infrared spectroscopy. , 2014, Food chemistry.

[20]  Y. H. Hui,et al.  Handbook of fruit and vegetable flavors , 2010 .

[21]  D. Dong,et al.  Analyzing Strawberry Spoilage via its Volatile Compounds Using Longpath Fourier Transform Infrared Spectroscopy , 2013, Scientific Reports.

[22]  D. Dong,et al.  Analysis and discrimination of grape spoilage via volatiles: a comparison between long optical path Fourier-transform-infrared spectroscopy and sensor arrays. , 2014, The Analyst.

[23]  E. Mahieu,et al.  Trend analysis of greenhouse gases over Europe measured by a network of ground-based remote FTIR instruments , 2008 .

[24]  Chris Dyer,et al.  Remote measurement of highly toxic vapors by scanning imaging Fourier-transform spectrometry , 2005, SPIE Optics East.

[25]  Zou Xiaobo,et al.  Vinegar Classification Based on Feature Extraction and Selection From Tin Oxide Gas Sensor Array Data , 2003 .

[26]  N. Magan,et al.  Use of an electronic nose for the early detection and differentiation between spoilage fungi , 1998, Letters in applied microbiology.

[27]  Lori A. Todd,et al.  Field Evaluation of a Transportable Open-Path FTIR Spectrometer for Real-Time Air Monitoring , 2002 .