Studying dynamic aroma release by headspace-solid phase microextraction-gas chromatography-ion mobility spectrometry...

Area of Science:

• Food Science
• Analytical Chemistry
• Sensory Science

Background:

• Understanding aroma perception in complex food matrices requires analyzing dynamic aroma release during simulated oral processing.
• Existing methods may have limitations in sensitivity, dynamic range, or robustness when applied to real food systems.

Purpose of the Study:

• To optimize, validate, and apply a novel method combining headspace-solid phase microextraction (HS-SPME) with gas chromatography-ion mobility spectrometry (GC-IMS).
• To assess the capabilities and limitations of this method for analyzing thirteen character impact aroma compounds.
• To demonstrate the application of the method for determining dynamic aroma release from a dairy matrix.

Main Methods:

• Optimization and validation of a coupled HS-SPME and GC-IMS technique.
• Analysis of thirteen volatile compounds with varying chemical properties.
• Investigation of instrumental parameters, including ion mobility spectrometry (IMS) inlet temperature.
• Application to a complex dairy food matrix.

Main Results:

• The IMS sample inlet temperature was successfully increased to 200°C without instrumental constraints.
• Linear calibration was achieved for eleven of thirteen compounds within a one-decade dynamic range.
• Limits of detection (LOD) ranged from 2.1-63.0 ppb and limits of quantitation (LOQ) from 7.2-210.1 ppb.
• Diacetyl was detected in negative IMS polarity, albeit with lower precision.
• Limitations included insufficient HS-SPME extraction time for caproic acid and inability to detect δ-decalactone due to GC temperature limits.
• Successful application to a dairy matrix for nine compounds, showing high robustness against matrix effects.

Conclusions:

• The developed HS-SPME-GC-IMS method is a robust and effective tool for analyzing dynamic aroma release from complex food matrices.
• The method demonstrates good sensitivity and linearity for many key aroma compounds.
• Further optimization may be needed to address limitations related to specific compound volatility and extraction efficiency for broader applications.