Use of fiber interface direct mass spectrometry for the determination of volatile flavor release from model food systems

Described in this paper is a fiber interface direct headspace mass spectrom etric system for the realtime measurement of flavor release. The system was optimized for the detection of the garlic aroma volatile, diallyl disulfid e, from water. Parameters investigated included interface temperature, flow rate through the fiber, flow rate through the sample vessel, and sample st ir rate. The delay time for detection of sample after introduction into the sample vessel was determined as 43 s. The system proved to be reliable and robust with no loss in sensitivity or contamination of the mass spectromet er over a 6 month period. The technique was applied to a homologous series of aliphatic alcohols from C-2 to C-7 Results showed that as polarity decre ased with increasing chain length the release of volatile into the headspac e was faster and gave a higher maximum intensity. Release of the garlic aro ma volatile from different commercial mayonnaise products clearly showed a decrease in the release of diallyl disulfide as fat content increased. Thes e results demonstrate the potential of using this technique as a tool for u nderstanding the complex interactions that occur between flavor compounds a nd the bulk food matrix.