Food products are routinely monitored for quality, authenticity, and safety. Analysis of food products may also be necessary due to off flavor or odor complaints. The aroma and flavor profiles of each product are unique and made up from a variety of semi-volatile and volatile compounds including aldehydes, ketones, acids, alcohols, terpenes, esters and other trace level components. The wide range of concentrations, polarities, and functional groups used in the composition of a flavor/aroma profile can make the analysis of the sample difficult. Techniques which are simple, use little or no solvent and encompass a wide range of analytes are desirable.

Alcoholic and non-alcoholic beverages are enjoyed by millions of people around the globe. The aroma and flavor profiles of each product are unique and made up from a variety of semi-volatile and volatile compounds including aldehydes, ketones, acids, alcohols, terpenes, esters along with various trace level compounds. Monitoring of these compounds is a necessity for beverage manufacturers in order to ensure consistent product quality. Analysis may also be necessary due to off flavor or odor complaints. The wide range of concentrations, polarities, and functional groups used in the composition of a flavor/aroma profile can make the analysis of the sample difficult.

Standard (SBSE) and Solvent-Assisted (SA-SBSE) Stir Bar Sorptive Extraction were both applied for profiling of flavor compounds in a matrix-heavy beverage sample. Unlike standard SBSE, SA-SBSE uses a solvent swollen polydimethylsiloxane (PDMS) stir bar for extraction and enhanced recovery of polar compounds. After extraction compounds were recovered from both stir bars by liquid desorption (LD) – large volume injection (LVI) and transferred to the analytical system for GC-MS analysis, with each sample run consecutively to give duplicate data files.

Headspace gas chromatography (HS-GC) is frequently used for the analysis of aroma compounds in food due to its practical advantages of simplicity, amenability to full automation, less contamination from non-volatile constituents and elimination or reduction of solvent use. There are several established HS techniques, e.g. static headspace (SHS), dynamic headspace (DHS), and head space solid phase micro-extraction (HS-SPME). However, these techniques are more selective for volatile and/or hydrophobic compounds and result in a partial chromatogram with an under-representation of hydrophilic and/or low vapor pressure aroma compounds.

Aroma Offi ce 2D (Gerstel K.K.) is an integrated software approach for simultaneous processing of both retention index (RI) and mass spectral (MS) data for rapid and improved identifi cation of fl avor compounds. The program can be integrated into Agilent Chemstation Software and searches are performed using CAS numbers of candidate compounds after library searching and corresponding automatically generated RI values. When MS signals are too weak to be used the software allows two RI values from orthogonal columns (after GC-O organoleptic evaluation) to be cross searched in the database. This offers a very useful additional identifi cation procedure for fl avor compounds.

This study shows the analysis of several commercially available coconut water products using a GC/MS system equipped with a versatile autosampler and sample preparation robot capable of performing a wide range of standard sample introduction techniques including thermal desorption. A fast and efficient analysis method based on stir bar sorptive extraction (SBSE) in combination with thermal desorption -GC/MS was developed for the determination of flavor compounds, pesticides, antioxidants, compounds migration from packaging materials, and off-flavors in coconut water.

In this study, a method was developed for quantitative determination of seven phenolic compounds in scotch whisky. Two different whisky brands were analyzed by Stir Bar Sorptive Extraction (SBSE), based on novel EG-Silicone Twisters, combined with thermal desorption-gas chromatography-mass spectrometry (TDGC- MS). Direct Large Volume Injection (LVI) -GC-MS was used as reference method. Optimized methods for LVI-GC-MS and SBSETD- GC-MS analysis were used for quantitative determination of the target compounds: phenol, o-,m-, and p-cresol, guaiacol, 4-ethylguaiacol, and 4-ethylphenol.

Direct injection for gas chromatographic profiling of alcoholic beverages is usually preferable, but where spirits and liquors contain appreciable amounts of non-volatile material, some mode of pre-treatment may be required to avoid both inlet and column contamination. This consideration applies in particular to products aged for extended periods in wooden barrels and especially products containing added sugar, as volatile artefacts from sugar decomposition in the hot injection port can also complicate the chromatogram.

Static (equilibrium) headspace sampling is commonly used for GC determination of volatiles in solid and liquid samples. Since this technique relies on the analyte partitioning between the sample and headspace and uses a fixed injection volume it may not provide adequate detection limits, particularly for higher molecular weight, higher boiling analytes, and for polar analytes in aqueous samples.

In this study, Thin Film Solid Phase Microextraction (TF-SPME) with a divinylbenzene/polydimethylsiloxane coating (DVB/PDMS) was used to extract off-odor compounds from paper product samples. The use of gas chromatography-mass spectrometry directly coupled with olfactory detection (GC-MS/O) enabled simultaneous detection of off-odor regions of the chromatogram and mass spectral identification of off-odor compounds. Identification of off-odor compounds in consumer goods is crucial for the manufacturer in order to identify the cause, take corrective action, and thereby maintain brand acceptance and success.