18C-30


Development of a real-time olfactometry software application for gas chromatography-olfactometry

L. L. COLBY and G. A. Reineccius. Dept. of Food Science & Nutrition, Univ. of Minnesota, 1334 Eckles Ave., Saint Paul, MN 55108

Gas chromatography-olfactometry (GC-O) is a broadly used technique in flavor research that involves the collection of both human and instrumental data. Several specific techniques have been developed including OSME, CharmAnalysisTM, AEDA, SNIF and NIF.  Of these methods, OSME has the timesaving benefit of not requiring repeated sample dilutions by recording both time-intensity and character of chromatographic peaks.  However, the actual mechanics and methods of using OSME vary from recording simple numbers for peak intensities to physical instrument component add-ons and expensive commercial software packages. 

Our objective was to develop an inexpensive software application to be used in gas chromatography-olfactometry using the OSME technique. 

Several attempts were made to capture and display real-time data using a variety of software.  LabViewTM was selected to develop a specialized “odor intensity virtual instrument” program.  Voice recording capabilities were added, but later removed to minimize strain on computer resources.  Aroma descriptions were recorded using separate digital recorders.  The program was tested for OSME usage during GC-O analysis of aroma compound mixtures and of Likens-Nickerson Cheddar cheese extracts. 

The program features an on-screen slider that is moved by the user's mouse to capture time intensity data and display it in real-time on the user's screen.  Program running time is practically unlimited for OSME applications (limited only by hard drive capacity) and has a data-sampling rate of up to 30/second.  Data output is easily opened as a text file or spreadsheet and can be overlaid with instrumental chromatograms.   We used the program to collect GC-O data on known aroma compound mixtures as well as Cheddar cheese extracts. 

Development of this application demonstrates an inexpensive technique that can be used in many labs to conduct GC-O research.  The program we developed may also function as an inexpensive, shareware, stand-alone application.

 

Session 18C, Food Chemistry: Food composition, analysis and volatiles
2:00 PM - 5:30 PM, Sunday PM Room Hall I-2

2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana