Comparison of Aroma Character Impact Volatiles of Thummong Leaves (Litsea petiolata Hook. f.), Mangdana Water Beetle (Lethocerus indicus), and a Commercial Product as Flavoring Agents in Thai Traditional Cooking

Article abstract of DOI:10.1021/acs.jafc.7b01499

Thummong (Litsea petiolata Hook. f.) is a tree native to southern Thailand. The leaves of this tree are highly aromatic and used to flavor Thai dishes in place of the traditional water beetle Mangdana (Lethocerus indicus) for religious and cultural reasons. Total and aroma-active volatiles from both flavoring materials were compared using gas chromatography-olfactory (GC-O) and gas chromatography-mass spectrometry (GC-MS). The volatiles from Thummong leaves and the Mangdana water beetle were collected and concentrated using headspace solid-phase microextraction. A total of 23 and 25 aroma-active volatiles were identified in Thummong leaves and Mangdana, respectively. The major aroma-active volatiles in Thummong leaves consisted of 7 aldehydes, 5 ketones, and 3 esters. In contrast, the aroma-active volatiles in the water beetle consisted of 11 aldehydes, 3 esters, and 2 ketones. Both had (E)-2-nonenal as the most intense aroma-active volatile. The water beetle character impact volatile (E)-2-hexenyl acetate was absent in the leaves, but its aroma character was mimicked by 11-dodecen-2-one in the leaves, which was absent in the beetle. In addition, a commercial Mangdana flavoring was examined using GC-O and GC-MS and found to contain only a single aroma-active volatile, hexyl acetate. All three flavoring sources exhibited similar aroma characteristics but were produced from profoundly different aroma-active volatiles.

Full text of DOI:10.1021/acs.jafc.7b01499

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Article
Comparison of aroma character impact volatiles of Thummong leaves
(Litsea petiolata Hook. f.), Mangdana water beetle (Lethocerus indicus)
and a commercial product as flavoring agents in Thai traditional cooking
Kanjana Mahattanatawee, Torsak Luanphaisarnnont, and Russell Rouseff
J. Agric. Food Chem., Just Accepted Manuscript • DOI: 10.1021/acs.jafc.7b01499 • Publication Date (Web): 06 Jul 2017
Downloaded from http://pubs.acs.org on July 7, 2017
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Page 1 of 19
Journal of Agricultural and Food Chemistry
Comparison of aroma character impact volatiles of
Thummong leaves (Litsea petiolata Hook. f.),
Mangdana water beetle (Lethocerus indicus)and a
commercial product as flavoring agents in Thai
traditional cooking
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Kanjana Mahattanatawee *, Torsak Luanphaisarnnont and Russell Rouseff
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Department of Food Technology, Faculty of Science, Siam University, 38 Petchkasem Road, Phasiꢀ
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charoen, Bangkok 10160, Thailand; Department of Chemistry and Center of Excellence for Innovation
in Chemistry, Faculty of Science, Mahidol University, 272 Rama VI Road, Ratchathewi, Bangkok,
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0400, Thailand; Citrus Research Institute of Southwest University , Chinese Academy of Agricultural
Sciences, National Citrus Engineering Research Center, Xiema, Beibei, Chongqing, China
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AUTHOR EMAIL ADDRESS kanjana@siam.edu Tel/Fax 662 867 8026
TITLE RUNNING HEAD : Character impact volatiles in Thummong and Mangdana
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Comparison of aroma character impact volatiles of Thummong leaves (Litsea petiolata
Hook. f.), Mangdana water beetle (Lethocerus indicus)and a commercial product as
flavoring agents in Thai traditional cooking
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ABSTRACT
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Thummong (Litsea petiolata Hook. f.) is a tree native to southern Thailand. The leaves of this tree are
highly aromatic and used to flavor Thai dishes in place of the traditional water beetle Mangdana
(Lethocerus indicus) for religious and cultural reasons. Total and aroma active volatiles from both
flavoring materials were compared using GCꢀO and GCꢀMS. The volatiles from Thummong leaves and
the Mangdana water beetle were collected and concentrated using headspace SPME. Twentyꢀthree and
twentyꢀfive aroma active volatiles, were identified in Thummong leaves and Mangdana respectively.
The major aroma active volatiles in Thummong leaves consisted of seven aldehydes, five ketones, and
three esters. In contrast, the aroma active volatiles in the water beetle consisted of 11 aldehydes and
three esters, and two ketones. Both had (E)ꢀ2ꢀnonenal as the most intense aroma active volatile. The
water beetle character impact volatile (E)ꢀ2ꢀhexenyl acetate was absent in the leaves, but its aroma
character was mimicked by 11ꢀdodecenꢀ2ꢀone in the leaves which was absent in the beetle. In addition,
a commercial Mangdana flavoring was examined using GCꢀO and GCꢀMS and found to contain only a
single aroma active volatile, hexyl acetate. All three flavoring sources exhibited similar aroma
characteristics but produced from profoundly different aroma active volatiles.
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KEYWORDS: Thai food flavoring, plant volatiles, insect volatiles
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INTRODUCTION
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One of the natural flavoring sources in traditional Thai foods comes from the volatile compounds of a
water beetle Mangdana (Lethocerus indicus). This edible insect is used for both flavoring and a source
of protein. In Thailand, villagers in the rural northeast and north, use a local water beetle as both a food
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and a flavoring . Only the male water beetle produces the desired aroma. The aroma from this beetle is
an important flavoring material in Thai cuisine, especially in “nam prig” or chili sauce dishes.
Previously (E)ꢀ2ꢀhexenyl acetate was reported as the character impact compound in Mangdana water
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beetle . This was subsequently confirmed by omission studies using an aroma reconstitution model .
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Thummong (Litsea petiolata Hook. f.) is a tree native to southern Thailand. The leaves of this tree are
highly aromatic and have been used in Thai cooking in place of the water beetle Mangdana as they have
a similar sensory character. There is also a cultural/religious reason for this substitution as the
population in southern Thailand is predominantly Muslim and insects are considered unclean. Both the
leaf and the insect are popular, natural flavoring agents in Thai traditional dishes but they have limited
availability in some areas and the beetle is only available during certain times of the year. A commercial
artificial Mangdana flavoring has been produced to replace the natural sources. Since all three sources of
flavoring are used for the same purpose in Thai traditional dishes there was a question if the similar
sensory characteristics were the result of the same character impact aroma active volatiles. The purpose
of this study was to compare and contrast the aroma active volatiles in these flavoring substances. The
resulting GCꢀolfactory profiles (based on the grouping of aroma active volatiles with similar character)
of both flavoring materials will be compared with each other as well as with the results from classical
sensory profiling (quantitative descriptive analysis).
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MATERIALS AND METHODS
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Chemicals
Hexanal, octanal, 1ꢀoctenꢀ3ꢀone, nonanal, methional, (E)ꢀ2ꢀnonenal, (Z)ꢀ2ꢀnonenal, octanol, (E,E)ꢀ2,4ꢀ
decadienal, decanal, (E,Z)ꢀ2,6ꢀnonadienal, (E,E)ꢀ2,4ꢀnonadienal, (E,Z)ꢀ2,4ꢀdecadienal, βꢀionone, ethyl
2ꢀmethylbutanoate, (Z)ꢀ3ꢀhexenal, ethyl pentanoate, (E)ꢀ2ꢀhexenal, ethyl hexanoate, (E)ꢀ2ꢀheptenal, 2ꢀ
methylꢀ3ꢀfuranthiol, cisꢀrose oxide, (E)ꢀ2ꢀheptenyl acetate, 1ꢀhexanol, dimethyl trisulfide, (E)ꢀ2ꢀhexenol,
(Z)ꢀ3ꢀhexenꢀ1ꢀol, cisꢀlinalool oxide, (E,E)ꢀ2,4ꢀoctadienal, butanoic acid, (E)ꢀ2ꢀdecenal, hexanoic acid,
2ꢀhexenoic acid, and guaiacol were obtained from SigmaꢀAldrich Co. LLC. Rꢀ(ꢀ)ꢀcarvone, βꢀ
damascenone, and acetaldehyde were gifts from Huangshan Kehong Bioꢀflavors Co. Ltd. China. Acetic
acid was purchased from Fisher. 2ꢀAcetylꢀ2ꢀthiazoline, (E)ꢀ2ꢀhexenyl acetate, (E)ꢀ2ꢀhexenyl butyrate,
and 2ꢀundecanone were gifts from Givaudan (Thailand) Ltd. 11ꢀDodecenꢀ2ꢀone was not commercially
available and was synthesized in the lab.
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Synthesis of 11-dodecen-2-one
To a solution of undecꢀ10ꢀenal (3.0 mL, 15 mmol) in THF (15 mL) at 0˚C under inert nitrogen
atmosphere, was added dropwise a solution of 3M methylmagnesium bromide in THF (5.5 mL, 16.5
mmol, 1.1 equiv.). The reaction was allowed to warm to room temperature. After 12 h, methanol (2 mL)
was slowly added dropwise. Saturated aqueous NH Cl (20 mL) was added. The reaction was diluted
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with EtOAc (20 mL) and poured into a separatory funnel. The layers were separated and the aqueous
layer was extracted with EtOAc (3 × 20 mL). The combined organic extracts were washed with brine
(60 mL), dried over Na SO , and concentrated. The crude dodecꢀ11ꢀenꢀ2ꢀol was used without further
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purification. To a solution of chromium (VI) oxide, toxic! (1.5 g, 15 mmol, 1 equiv.) in 4 M sulfuric
acid (95 mL) at 0˚C, was added a solution of crude dodecꢀ11ꢀenꢀ2ꢀol in acetone (15 mL) dropwise over
15 min. The reaction mixture was allowed to warm to room temperature. After 6 h, the reaction
mixture was diluted with EtOAc (100 mL) and poured into a separatory funnel. The layers were
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separated and the aqueous layer was extracted with EtOAc (3 × 80 mL). The combined organic extracts
were washed with brine (200 mL), dried over Na SO , and concentrated. Flash column
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chromatography (5% EtOAc in hexane) gave the desired product as colorless oil (1.85 g, 68% over two
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steps). The observed NMR spectra of the synthesized dodecꢀ11ꢀenꢀ2ꢀone consisted of: H NMR (400
MHz, CDCl ) δ 5.80 (dd, 1H, J = 10, 17 Hz); 4.90−5.00 (m, 2H); 2.41 (t, 2H, J = 7.5 Hz); 2.13 (s, 3H);
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1.90−2.10 (m, 2H); 1.54−1.59 (m, 2H); 1.25−1.38 (m, 10H). C NMR (100 MHz, CDCl ) δ 209.3,
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139.2, 114.1, 43.8, 33.8, 29.8, 29.3, 29.2, 29.1, 29.0, 28.9, 23.8. The observed spectral data matched
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that of the published NMR spectra of dodecꢀ11ꢀenꢀ2ꢀone . H NMR (CDCl ): d = 1.19–1.56 (m, 10 H),
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1.95–2.42 (m, 7 H), 2.38 (t, 2 H, J = 7.3 Hz), 4.87–5.00 (m, 2 H), 5.67–5.87 (m, 1 H). C NMR
(CDCl ): d = 23.8, 28.8, 29.0, 29.1, 29.2, 29.3, 29.8, 33.7, 43.7, 114.0, 139.0, 209.2.
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Sample and Headspace Sampling
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Thummong leaves were cut into 0.5 cm small pieces within three days of being harvested. One gram of
cut leaves was placed into a 40 mL glass vial (LaꢀPhaꢀPack, Germany). The vial headspace was purged
with nitrogen before sealing with a Teflonꢀcoated septum. The sample was equilibrated at 40 °C for 15
min in a water bath and a 2 cm 50/30 µm divinylbenzene/Carboxen/ꢀpolydimethylsiloxane
(DVB/Carboxen/PDMS) Stable Flex fiber (Supelco, Bellefonte, PA) was exposed to the leaf headspace
volatiles for 30 min. The sorbed leaf volatiles were introduced into the GC injector set at 200 °C. Fresh
frozen water beetle Mangdana was purchased from a local market. The sample preparation of the beetle
was the same as the leaf except using only five grams of the cut up water bug. A commercial liquid
Mangdana flavoring was purchased from a local supermarket in Bangkok, Thailand and a100 µL aliquot
analysed in the same manner as the leaf and bug.
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Gas Chromatography-FID/Olfactometry
Volatiles were separated and evaluated using an Agilent GC 7890 equipped with a sniffing port.
Samples were run separately on both a polar (DBꢀwax, J&W Scientific, Folsom, CA; 30 m. × 0.32 mm.
i.d. × 0.5 µm film thickness) and a 5% phenyl, 95% dimethylꢀpolysiloxane nonpolar column (Zebron
ZBꢀ5, Phenomenex, Torrance, CA; 30 m. × 0.32 mm. i.d. × 0.5 µm film thickness,). Oven temperature
was programmed from 40 to 220 °C at 7 °C/min for both columns. Helium was used as carrier gas at a
flow rate of 1.5 mL/min. Injector and detector temperature were 200 °C and 250 °C, respectively. A 0.75
mm. injector liner was employed to improve peak shape and chromatographic efficiency. Injections
were splitless. The column effluent was split, 1/3rd of the flow was conducted to the FID and the other
2/3rds to the olfactory port for sniffing with previously mixed humid air. Two assessors, trained in a
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similar way to Dreher and coworkers , evaluated each sample in triplicate on both ZBꢀ5 and DBꢀWax
columns. Odor descriptors and retention times were recorded for every sample. Assessors rated odor
intensity continuously throughout the chromatographic separation process using a linear potentiometer
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as previously described . Intensities of all odorꢀactive compounds of each GCꢀO run were normalized so
the highest intensity from each assessor was given a score of 10. The normalized intensities of all the
runs were then averaged. A peak was considered odorꢀactive only if at least half of the panel responses
found a similar odor quality at the same retention time. Identification of volatiles was determined by
comparing standard Linear Retention Index (LRI) values from both FID and MS data from samples with
those from authentic standards. MS fragmentation patterns were also used to aid identification when
available. Identifications were confirmed by comparing odor quality of standards and unknowns at the
same retention time. Since the primary goal of this study was to determine character impact volatiles, the
aroma character of the unseparated SPME extract was compared to that of the initial samples. The
sorbed SPME volatiles were introduced to GC injection port and carried to the sniffer using a short (1
m.) fused silica column to confirm the similarity to the original sample.
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15 Mass Spectrometry
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GCꢀMS was employed to confirm the identities of the odorꢀactive volatiles identified in the GCꢀO
experiments. Headspace SPME volatiles were separated and analyzed using an Agilent GC 7890
quadrupole mass spectrometer and a DBꢀWax capillary column (30 m. × 0.25 mm. i.d. × 0.50 µm film
thickness). The carrier gas was helium in the constant flow mode of 2 mL/min. The source was set at
200 °C, the transfer line was maintained at 260 °C, and the injector was at 200 °C. The oven
temperature program consisted of a linear gradient from 40 to 220 °C at 7 °C/min with a 2 min final
hold. Electron ionization in the positive ion mode was used (70 eV), either scanning a mass range from
m/z 25 to 300 or acquiring data in the selected ion mode. Mass spectra matches were made by
comparison with NIST 2005 version 2.0 standard spectra (NIST, Gaithersburg, MD). Only those
compounds with spectral fit values ≥ 800 were considered positive identifications. Authentic standards
were also used to confirm identifications whenever available.
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27 Sensory Aroma Profile Analysis
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The aroma attributes for Thommong leaf and Mangdana beetle were evaluated using panels from
Thailand who have had lifeꢀlong experiences with both samples. One gram of chopped leaf and 3 grams
of Mangdana beetle were separately presented to the panel in 40 ml screw cap glass vials at room
temperature. The panel consisted of fifteen experienced panelists (age 22ꢀ50 years, 13 females and 2
males) and employed consensus sensory description. The eight consensus attributes consisted of: “sweet
herbaceous”, “metallic”, “green”, “sweet”, “cheesy”, “creamy”, “cooked” and “savory”. Eight reference
solutions for each of the aroma attributes were prepared at 50ꢀfold greater than their odor thresholds in
water: 2ꢀhexenyl acetate (sweet herbaceous), (E)ꢀ2ꢀnonenal (metallic), hexenal (green), vanillin (sweet),
butanoic acid (cheesy), cream milk powder (creamy), methional (cooked) and chicken stock (savory).
The panelists were asked to rate the intensity of eight attributes in each sample on a scale from 0 to 5 (0
stands for not perceivable and 5 for very high intensity).
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39 RESULTS AND DISCUSSION
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40 GC-O Aroma Active Volatiles
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As shown in Table 1, a total of 23 aroma active volatiles were observed in Thummong leaves and 25
aroma volatiles in the Mangdana water beetle using GCꢀOlfactometry, GCꢀO. Although a total of 43
aroma active volatiles were observed from both samples, only five volatiles were common to both
samples. Aldehydes constituted the major aroma active functional group (17) listed in Table 1, followed
by equal numbers of esters, alcohols, and ketones (six each).
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The overall intense, sweet, herbaceous character of both samples was due to completely different
volatiles. In the case of Thummong leaves the intense herbaceous aroma was due to 11ꢀdodecenꢀ2ꢀone,
but in the case of the Mangdana water beetle, the same aroma character was produced by (E)ꢀ2ꢀhexenyl
acetate. Both of these character impact volatiles were confirmed by matching sensory descriptors using
GCꢀO as well as matching retention times of standards as well as corresponding MS spectral matches.
A commercial source of (E)ꢀ2ꢀhexenyl acetate was used as a standard but 11ꢀdodecenꢀ2ꢀone had to be
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synthesised as no commercial source was available. Both compounds were described as intensely
sweet herbaceous which is surprising as they differ profoundly in terms of general structure and
functional group (ester versus a ketone). The character impact volatile in Mangdana water beetle has
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been previously reported as (E)ꢀ2ꢀhexenyl acetate and was later confirmed as the only character impact
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volatile in omission studies of an aroma reconstitute model . This volatile also occurs naturally in many
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fruits such as strawberry, and yellow passion fruit .
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The five aroma volatiles common to both samples consisted of (Z)ꢀ3ꢀhexenal, methional, (E)ꢀ2ꢀnonenal,
guaiacol, and βꢀionone. Both samples had a strong metallic/fatty aroma component due to (E)ꢀ2ꢀ
nonenal. The lower molecular weight (Z)ꢀ3ꢀhexenal produced a stronger (8 versus 2 intensity) green
aroma in the water beetle than the leaf. The remaining three common aroma volatiles, methional,
guaiacol and βꢀionone where all about twice as intense in the water beetle as in the leaf. In fact, the
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sum of all the aroma active intensities in the water beetle were almost twice as high as the total
intensities from the leaves (176 versus 97).
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As seen in Table 1, the functional group composition was somewhat different between the leaf and the
beetle. The leaves were characterized by fewer aldehydes (seven versus eleven) and more ketones (five
versus two). Both samples contained the same number of alcohols and esters (three and three). The
water beetle contained three volatile acids whereas the leaf contained none.
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In an attempt to compare the overall aroma impressions of the Thummong leaf and the Mangdana water
bug using GCꢀO data, the individual aroma attributes and their corresponding aroma intensities were
classified into eight categories. Those aroma volatiles with similar sensory descriptors were placed in
the same group. The categories consisted of: fatty/waxy, metallic, green, sweet/herbaceous, cheesy,
fruity/floral, cooked, and meaty/sulfur. These aroma quality groupings were chosen to match as closely
as possible to the consensus aroma descriptors developed in a parallel sensory study which will be
discussed later. These GCꢀO category results are shown in the radar or spider web graphics in Figure
2A.
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Both samples were characterized by having strong fatty/waxy, metallic, green, and fruity/floral
characteristics as determined by summing the aroma intensities in each category. Both character impact
compounds were major contributors to the sweet herbaceous category and accordingly rated either 9 or
10. However, the relative contribution of the character impact compound was greater in the leaf because
it contained less aroma active volatiles in other categories. Both samples contained similar total aroma
intensities in the metallic, green, and cooked aroma categories. The water beetle exhibited greater
fatty/waxy and cheesy total intensities compared to the leaf. On the other hand the leaf had stronger
fruity/floral and meaty/sulfur relative intensities. Overall, the summarized aroma category profiles were
reasonably similar for both products.
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86 Sensory Panel Aroma Descriptive Analysis
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Average sensory panel descriptive analysis scores for the eight consensus attributes are shown in Figure
2B. There were similar panel scores for only two attributes, sweet herbaceous and sweet. The similar
intense sweet herbaceous scores were probably due to the respective character impact volatiles observed
in the GCꢀO studies. The panel indicated that the leaf contained strong green, sweet herbaceous, and
metallic aroma attributes. However, the leaf exhibited very weak creamy, cooked, and savory scores. In
contrast, the water beetle possessed strong aroma intensities in these same categories, namely; cooked,
savory, creamy, and cheesy attributes. These scores on the left hand side of the spider web diagram are
so profoundly different between the two samples, suggesting that the panel found these two flavor
sources to be different even though the major character sensory attribute was very strong in both cases.
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In comparing the GCꢀO patterns with the sensory patterns (Figures 2A and 2B), it is important to keep in
mind that the aroma values are evaluated in very different ways. In GCꢀO, aromas are evaluated
individually whereas sensory analysis evaluates mixtures of aroma compounds. It is probably the reason
why some of the sensory panel aroma attributes such as “creamy” or “savory” were not observed in the
GCꢀO study. These attributes were probably not due to a single volatile, but rather combinations of
aroma volatiles. Therefore, where there is agreement of GCꢀO summary data with such sensory
attributes as “green”, “metallic”, and “sweet herbaceous”, it is because these sensory attributes are
largely due to single components rather than mixtures.
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04 GC-MS Chromatograms
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GCꢀMS was carried out to evaluate all of the major volatiles in the three samples and to confirm the
identities of the character impact compounds in the three samples tentatively identified in the GCꢀO
studies. The total ion chromatograms, TIC, of the three samples are shown in Figure 3 with major peaks
identified in the figure caption. It can be seen from the relative peak heights that the character impact
volatiles for both Thummong leaves (11ꢀdodecenꢀ2ꢀone) and Mangdana water beetle (Eꢀ2ꢀhexenyl
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acetate) were also the dominant peaks. They represent a rare example where the character impact
volatile is also the single largest peak in the chromatogram (Fig. 3). The fragmentation patterns of the
character impact volatile from Mangdana (A), (E)ꢀ2ꢀhexenyl acetate, Thummong leaf (B) matched both
those in the spectral library and standards, thus confirming their identifications. They have similar
smells but are produced from totally different chemical compounds. There are limited reports of the
aroma active volatile, 11ꢀdodecenꢀ2ꢀone, but it has been reported as a specific ketone volatile in
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Changyu XO (a Chinese brandy) comparable to Hennessy XO (a wellꢀknown French liquor) .
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17 Commercial Mangdana flavoring
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A commercial Mangdana flavoring was also evaluated using GCꢀO and GCꢀMS. In the case of GCꢀO,
only a single aroma active peak was observed at a retention time different than either of the other two
character impact volatiles. The TIC chromatogram shown in Figure 3C is also very simple, consisting
of essentially one peak. The fragmentation pattern of this peak matched almost perfectly with hexenyl
acetate. Standard hexenyl acetate produced the same GCꢀO retention time and sensory response. Thus
the commercial product is not natural nor nature identical. From a chemical point of view it is
interesting in that it uses a chemical analogue of the water beetle character impact volatile, (E)ꢀ2ꢀ
hexenyl acetate, without the double bond which is probably a more stable and/or a less expensive
material.
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ACKNOWLEDGMENT
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We are grateful to Givaudan (Thailand) Ltd., and Huangshan Kehong Bioꢀflavors Co. Ltd. China for the
generous gift of authentic aroma standards. We also express our sincere thanks to the panelists from the
laboratory Department of Food Technology, Siam University. The work has been financially supported
from Siam University.
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REFERENCES
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(1) Pemberton, R. W. The use of the Thai giant waterbug, lethocerusꢀindicus (hemiptera,
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(2) Mahattanatawee, K.; Rouseff, R. L. Character impact volatiles of Thai water bugs “Mangda”
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(Lethocerus indicus). In: Proceedings of the 9 Wartburg symposium on flavour chemisty and
biology: Advances and challenges in flavor chemistry and biology. Freising, Germany 2010,
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(3) Kiatbenjakul, P.; Intarapichet, K.; Cadwallader, K.R. Characterization of potent odorants in male
giant water beetle (Lethocerus inducus Lep. And Serv.), an important edible insect of Southeast
Asia. Food Chem. 2015, 168, 639ꢀ647.
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(4) Schulze, A.; Giannix, A. Oxidation of alcohols with catalytic amounts of IBX. Synthesis 2006, 2,
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(5) Dreher, J. G.; Rouseff, R. L.; Naim, M. GCꢀolfactometric characterization of aroma volatiles
from the thermal degradation of thiamine in model orange juice. J. Agric. Food Chem. 2003, 51,
3097ꢀ3102.
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(6) Bazemore, R.; Goodner, K.; Rouseff, R. Volatiles from unpasteurized and excessively heated
orange juice analysed with solid phase microextraction and GCꢀOlfactometry. J. Food Sci. 1999,
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(7) Schieberle, P.; Hofmann, T. Evaluation of the character impact odorants in fresh strawberry
juice by quantitative measurements and sensory studies on model mixtures. J. Agric. Food
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(8) Werkhoff, P.; Guntert, M.; Krammer, G.; Sommer, H.; Kaulen, J. Vacuum headspace method in
aroma research: flavor chemistry of yellow passion fruits. J. Agric. Food Chem. 1998, 46, 1076ꢀ
1093.
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(9) Zhao, Y.P.; Wang, L.; Li, J.M.; Pei, G.R.; Liu, Q.S. Comparison of volatile compounds in two
brandies using HSꢀSPME coupled with GCꢀO, GCꢀMS and sensory evaluation. S. Afr. J. Enol.
Vitic. 2011, 32, 9ꢀ20.
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FIGURE CAPTIONS
Figure 1 Synthesis of 11ꢀdodecenꢀ2ꢀone
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Figure 2 (A) Spider graph of GCꢀO aroma active compounds from Table 1 which have been grouped
according to similar odor. The group values are graphed as percent of total intensity from each product
for each category. Mangdana beetle (ꢀꢀꢀ) and Thummong leaves (ꢀꢀꢀ) (B) Average sensory panel
Quantitative Descriptive values comparing scores from Mangdana beetle (ꢀꢀꢀ) and Thummong leaves (ꢀ).
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Figure 3 Comparison of the character impact volatile from Mangdana beetle (A), Thummong leaves (B)
and commercial Mangdana flavoring (C). a = hexanal, b = (E)ꢀ2ꢀhexenal, c = (E)-2-hexenyl acetate, d =
(E)ꢀ2ꢀhexenol, e = (E)ꢀ2ꢀhexenyl butyrate, f = 2ꢀhexenoic acid, g = (E)ꢀ2ꢀheptenal, h = cisꢀrose oxide, i
= nonanal, j = (E)ꢀ2ꢀnonenal, k = 2ꢀundecanone, l = 11-dodecen-2-one, m = carvone, n = (E,Z)ꢀ2,4ꢀ
decadienal, o = hexyl acetate
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Table 1 Aroma active volatiles in Mangdana water beetle and Thummong leaves
LRI MS
Wax DBꢀ5 Ident.
Intensity
Lea
Aroma
Group
Identification
Odor Descriptors
Bug
f
1
2
3
4
5
6
7
8
9
Acetaldehyde
ethyl 2ꢀmethylbutanoate
Hexanal
(Z)ꢀ3ꢀhexenal
ethyl pentanoate
(E)ꢀ2ꢀhexenal
ethyl hexanoate
Octanal
(E)ꢀ2ꢀheptenal
1ꢀoctenꢀ3ꢀone
(E)ꢀ2ꢀhexenyl acetate
2ꢀmethylꢀ3ꢀfuranthiol*
718
1063
1076
1128
1142
1215
1244
1279
1284
1292
539 TIC solvent like
847 TIC fruity
795 TIC green
795 EIC green
899 TIC fruity
855 EIC green, metallic, sweet
998 TIC fruity
982 EIC citrusy
954 TIC green
2
2
F
C
C
F
C
F
6
8
2
1
9
8
2
2
F
C
B
D
G
1
1
1
0
1
2
977 EIC mushroom
6
9
1323 1020 TIC sweet herbaceous
1326 861 cooked, meaty
1363 1157 TIC floral
*
4
3
1
3
cisꢀrose oxide
F
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
(E)ꢀ2ꢀheptenyl acetate
1ꢀhexanol
1366
1393
1400
1403
1407
TIC green, fatty
865 TIC green, leaf
985 sulfury, cabbageꢀlike
8
6
C
C
H
C
C
C
E
7
dimethy trisulfide*
*
10
880 TIC green, leafy
(
E)ꢀ2ꢀhexenꢀ1ꢀol
(Z)ꢀ3ꢀhexenꢀ1ꢀol
nonanal
847 TIC fresh, green, grassy
3
1
1410 1100 TIC green, soapy
acetic acid
1439
1442
680 TIC vinegar
909 cooked potato
10
8
methional*
*
4
4
G
F
F
cisꢀlinalool oxide
(E)ꢀ2ꢀhexenyl butanoate
Decanal
(Z)ꢀ2ꢀnonenal
(E)ꢀ2ꢀnonenal
1ꢀoctanol
(E,Z)ꢀ2,6ꢀnonadienal
(E,E)ꢀ2,4ꢀoctadienal
butanoic acid
2ꢀundecanone
(E)ꢀ2ꢀdecenal
11ꢀdodecenꢀ2ꢀone
(E,E)ꢀ2,4ꢀnonadienal
Rꢀ(ꢀ)ꢀcarvone
2ꢀacetylꢀ2ꢀthiazoline*
(E,Z)ꢀ2,4ꢀdecadienal
(E,E)ꢀ2,4ꢀdecadienal
hexanoic acid
Guaiacol
1467 1214 TIC floral, green
1471 1193 TIC floral
1501 1201 TIC fresh mint, citrusy
1519 1149 EIC fatty, metallic, geranium
1529 1161 TIC metallic, fatty
1578 1078 EIC fatty
5
5
9
10
7
C
A
B
A
C
A
E
A
C
D
A
C
G
A
A
E
10
5
1594 1161 TIC green, metallic
1607 1110 EIC fatty
4
8
1617 1609 TIC cheesy, sweaty
1618 1300 TIC waxy, fatty sweet
1665 1250 EIC green, fatty
1676 1287 TIC sweet herbaceous
1710 1220 EIC fatty
1745 1245 TIC minty
1750 1109
1796 1313 TIC fatty, green
1806 1284 EIC fatty , cooked grain
1837 1085 TIC sweaty, cheesy
1851 1091 EIC smoke, medicine
1855 1395 EIC sweet honey
1934 1496 EIC raspberry, floral
1958 1614 EIC musty, fatty, sweaty
9
10
2
5
5
6
*
cooked jasmine rice
4
4
9
4
2
3
5
G
D
F
βꢀdamascenone
βꢀionone
2ꢀhexenoic acid
9
8
A
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Volatile compounds identified by matching: retention characteristics on both wax and DBꢀ5 columns,
their sensory aroma characteristics, and their MS spectra with those of authentic standards.
TIC = full spectrum identification match, EIC = extraction ion chromatograms retention time match
using a single base ion. * Tentatively identified on the basis of aroma descriptors and retention time
matches with literature values. Aroma group categories: A = fatty/waxy, B = metallic, C = green, D =
sweet/herbaceous, E = cheesy, F = fruity/floral, G = cooked, H = meaty/sulfur.
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Figure 1.
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Figure 2.
sweet
fatty/waxy
herbaceous
3
2
2
1
1
0
5
0
5
0
5
0
5
.0
4
.0
meaty/sulfur
cooked
metallic
savory
metallic
3
.0
.0
2
1.0
0.0
green
cooked
green
sweet/herba
ceous
creamy
sweet
fruity/floral
cheesy
cheesy
A
B
3
3
18
19
3
3
3
3
3
3
3
3
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21
22
23
24
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Figure 3.
e
f A
b
c
c
d
(
E)-2-hexenyl acetate
a
l
B
C
l
k
1
1-dodecen-2-one
j
m
i
h
g
n
o
o
Hexyl acetate
0
2
4
6
8
10
12
14
16
18
20
Time – Minutes (Wax)
3
3
29
30
3
31
3
3
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33
3
3
3
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TOC graphic
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