Page 16 - Shimadzu Journal vol.3 Issue2

Flavor Release Evaluation

Development of GC-MS analysis methods for
essential oil distributed nonuniformly in foods

Takehiko Sagawa, Ph.D, Research and Analysis Center, Research and Product Development Divsion, Development and
Manufacuturing Group, S&B Foods Inc.
Keywords: DMI-GC/MS, thyme, coriander, essential oil

Abstract
The quality control of aroma in spices and herbs is essential for the development of food products in companies dealing with spices and
herbs. Product development in food companies involves quality control; it is also important for providing information about spices and
herbs, which are required in several recipes or for marketing purposes to explain their significance in cooking. In this study, we focus on
essential oils localized in foods, which affect their flavor. Furthermore, the role and possibility of chemical analysis for improving good
flavor are examined.

Introduction
analysis of a non-purified sample with direct introduction of the
A flavor influencing the gusto of the foods is constructed in sample. The device has a component with a programmed
“aroma” and “taste”. Recently, the importance of the effects of temperature vaporizing (PTV) injector and a specialized glass liner
aroma on gusto has been attracting significant attention. Hence, with space for a microvial holding the solid sample.
odor-active compounds in foods have been examined by chemical Several studies using the DMI device have reported the analysis of
analysis because the understanding and control of food aroma are pesticide residues and the combination with the quick, easy, cheap,
essential for the development of food products. A previous study effective, and rugged method, a known simple purification
utilizes a different approach involving the sensory analysis of foods method. One case described a method in which nonvolatile
3,4
using uniform and non-uniform model food products containing compounds were kept in a specific microvial during analysis to
odor-active compounds. However, with this approach, food avoid instrument and capillary GC column contamination, in which
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product developers could not correlate the results obtained from volatile compounds were drained into the split vent before starting
6
chemical analyses with those obtained from the sensory GC/MS analysis for cleanup in a glass liner. In another case,
evaluations of foods. One way to solve this issue is to use screening analysis for polycyclic aromatic hydrocarbons was
homogeneous analytical samples for chemical analysis. However, performed using a DSI device. A small amount of atmospheric
7
food products are complex as well as non-homogeneous from both aerosols was collected directly into a glass liner for analysis. The
physical and chemical viewpoints. Herein, we report two examples efficacy of this method for microchemical screening analysis was
for the measurement of odor-active compounds localized in foods. also reported in this study.
The first example describes the measurement of an aroma DMI-GC/MS has been used with plant tissue to evaluate the quality
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compound in herbs involving the migration of thymol from fresh of herbal medicine with chemical fingerprinting and to analyze
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thyme to cod fish in the case of “foil-roasted cod fish with fresh methyl salicylate in plants infected with the tobacco mosaic virus.
thyme”. The second example describes the measurement of an A DMI device allows various introductions for GC analysis. In this
odor-active compound (E)-2-dodecenal localized in coriander leaves study, we developed a DMI-GC/MS analysis technique for
and roots. In both cases, direct sample introduction-gas extraction of volatile compounds from small tissues of a food and
chromatography–mass spectrometry (DMI-GC/MS) analysis was analysis of the quality of the essential oil in foods.
employed. This analytical method permits the GC/MS measurement of volatile
The DMI device reported by Amirav et al. performed well in the compounds using milligram amounts of sample.
1,2

1. Thyme flavor in the case of foil-roasted cod fish with fresh thyme
– Measurement of thymol localized in the case of prepared cod fish –
We employed DMI-GC/MS for analyzing the aroma of prepared foods. For example, we confirmed the migration of thymol
from thyme to a slice of cod fish in foil-roasted cod fish with fresh thyme.

Sample preparation
Fig. 1 shows the preparation of DMI-GC/MS analysis of the cod fish following which GC/MS analysis was performed.
tissues. The tissue section was inserted into the specialized microvial We subjected the samples thus prepared to DMI-GC/MS analysis to
(30 µL) carefully to avoid breakage (Fig. 1). The vial was then set in investigate the migration of thymol from a micro viewpoint.
the glass liner of the Optic4 (DMI liner, ATAS GL International B.V.),

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