Methyl Propyl Disulfide Research Articles

Characterization of Key Odorants in Scallion Pancake and Investigation on Their Changes during Storage.

To characterize key odorants in scallion pancake (SP), volatiles were extracted by solvent extraction-solvent assisted flavor evaporation. A total of 51 odor-active compounds were identified by gas chromatography-olfactometry (GC-O) and chromatography–mass spectrometry (GC-MS). (Z/E)-3,6-Diethyl-1,2,4,5-tetrathiane was detected for the first time in scallion food. Application of aroma extract dilution analysis to extracts showed maltol, methyl propyl disulfide, dipropyl disulfide and 2-pentylfuran had the highest flavor dilution (FD) factor of 4096. Twenty-three odorants with FD factors ≥ 8 were quantitated, and their odor active values (OAVs) were calculated. Ten compounds with OAVs ≥ 1 were determined as the key odorants; a recombinate model prepared from the key odorants, including (E,E)-2,4-decadienal, dimethyl trisulfide, methyl propyl disulfide, hexanal, dipropyl trisulfide, maltol, acetoin, 2-methylnaphthalene, 2-pentylfuran and 2(5H)-furanone, successfully simulated the overall aroma profile of SP. The changes in odorants during storage were investigated further. With increasing concentrations and OAVs during storage, hexanal became an off-flavor compound.

In-Vitro Evaluation of the Antioxidant and Anti-Inflammatory Activity of Volatile Compounds and Minerals in Five Different Onion Varieties

Onions contain high antioxidants compounds that fight inflammation against many diseases. The purpose was to investigate some selected bioactive activities of onion varieties (Yellow, Red, Green, Leek, and Baby). Antioxidant assays and anti-inflammatory activities such as NO production with the addition of some bioactive components were determined and analyzed by using a spectrophotometer. Gas chromatography and mass spectrometry (GC–MS) was used for the volatile compounds, while an Atomic absorption spectrometer was used for mineral determinations. Red variety achieved the highest antioxidant activities. The total flavonoids were between (12.56 and 353.53 mg Quercetin/gin dry weight) (dw) and the total phenol was (8.75–25.73 mg/g dw). Leek, Yellow and Green extracts achieved highly anti-inflammatory values (3.71–4.01 μg/mL) followed by Red and Baby extracts, respectively. The highest contents of sodium, potassium, zinc, and calcium were established for Red onions. Furfuraldehyde, 5-Methyl-2-furfuraldehyde, 2-Methyl-2-pentenal, and 1-Propanethiol were the most predominant, followed by a minor abundance of the other compounds such as Dimethyl sulfide, Methyl allyl disulfide, Methyl-trans-propenyl-disulfide, and Methyl propyl disulfide. The results recommend that these varieties could act as sources of essential antioxidants and anti-inflammatories to decrease inflammation and oxidative stresses, especially red onions that recorded high activities.

Multi-element (13C, 2H and 34S) bulk and compound-specific stable isotope analysis for authentication of Allium species essential oils

Pure and natural essential oils of Allium species are primarily used in the food industry, but due to their low yield, production quantities can be difficult to achieve and thus can be highly expensive. Due to these problems, adulterations are a reality in this field. The purpose of this research is to develop a multi element stable isotope analysis methodology for authentication of the essential oils of leek, onion, shallot, and chive. Naturalness of these essential oils was achieved by assessment of compound specific δ13C and δ34S: an addition of 5% of synthetic compound can be detected. Chemometric models were undertaken to assess purity by distinction of the Allium samples according to their species origin using bulk stable and compound specific δ13C, δ2H, δ34S, and compositions of their major metabolites dipropyl disulfide, dipropyl trisulfide, methyl propyl disulfide, and methyl propyl trisulfide.

Chinese onion (Allium chinense), an evergreen vegetable: A brief review

The history of using medicinal herbs and plant dates back to the ancient times. Chinese onion (Allium chinense) is fa­mous as a plant for both food and medicinal purposes. It is wi­dely cultivated as a vegetable and native to China. Its bulbs are commonly processed into pickles and spices. The bulb is anthel­mintic, anti-inflammatory, antiseptic, antispasmodic, carminati­ve, diuretic, expectorant, febrifuge, hypoglycaemic, hyptensive, lithontripic, stomachic and tonic. It can be also used to prevent oral infection and tooth decay. The most important chemical con­stituents of the essential oil derived from Allium chinense are: dimethyl disulfide, diallyl sulfide, allyl isothiocyanate, methyl allyl disulfide, methyl propyl disulfide, α-pinene, dimethyl trisul­fide, β-pinene, 1,3-dithiane, limonene, diallyl disulfide, linalool, methyl allyl trisulfide, methyl propyl trisulfide, dimethyl tetra­sulfide, diallyl trisulfide, diallyl thiosulfinate, and allyl methyl tetrasulfide.

Pollution status of volatile organic sulfur compounds causing odor in Xi River and factors influencing spatial distribution

Abstract This study investigated the pollution status of volatile organic sulfur compounds (VOSCs) and the factors influencing their spatial distribution in the Xi River in Shenyang, China. A method for simultaneous determination of 14 VOSCs that cause odor in water samples was developed by using purge and trap coupled with gas chromatography and a flame photometric detector. The results indicated that each target compound could be identified from 15 sampling sites, and the total concentration of 14 VOSCs ranged from 2.575 to 52.981 μg L−1. Dimethyl sulfide (DMS) was the most important contaminant with an average concentration of 4.029 μg L−1, a detection rate of 93.33% and a variation coefficient of 0.72. The VOSCs were primarily distributed in suburban and rural sections, and the suburban section was the worst in regard to pollution by VOSCs. Dimethyl trisulfide was primarily distributed in urban and suburban sections of the Xi River due to industrial emissions. Ethanethiol, DMS, and ethyl methyl sulfide, which are typical by-products of microbial anaerobic decomposition from domestic wastewater, were found in abundance in the suburban section. Diethyl sulfide, diethyl disulfide, methyl propyl disulfide, and 1-propyl disulfide representing agricultural nonpoint source pollution were mostly distributed in the rural section.

Evaluation of the Perceptual Interaction among Sulfur Compounds in Mango by Feller's Additive Model, Odor Activity Value, and Vector Model.

The volatile compounds found in mangoes (Mangifera indica L.) obtained from three cultivars (TN, Tainong no. 1; KT, Keitt; and ZL, Zill; grown in China) were comprehensively analyzed by gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and GC-flame photometric detection (GC-FPD) analyses. The results showed that 42, 35, and 45 compounds were identified in the TN, KT, and ZL samples, respectively. From these compounds, 19, 14, and 20 compounds were identified as important odorants with odor activity values (OAVs) greater than 1. Of these, 5, 7, and 5 sulfur compounds were respectively identified in the three samples by FPD. Importantly, methanethiol, ethanethiol, 1-propanethiol, methyl propyl disulfide, and 3-mercapto-1-hexanol were detected for the first time in mango. Five sulfur compounds were selected to study interactions using Feller's additive model, OAV, and Vector model. Among these mixtures, six mixtures exhibited a masking effect, three mixtures presented an additive effect, and one mixture showed a synergistic effect.

Responses to Host Plant Volatiles and Identification of Odorant Binding Protein and Chemosensory Protein Genes in Bradysia odoriphaga

The chive maggot Bradysia odoriphaga Yang et Zhang (Diptera: Sciaridae) is a devastating agricultural pest that feeds on liliaceous vegetables and edible mushrooms. The shared host plant volatiles and chemosensory genes of B. odoriphaga may together play crucial roles for insects to identify their host. However, the responses of B. odoriphaga to host volatiles remain unclear. Electroantennography (EAG) and behavioral bioassays were performed on 12 volatiles shared in Allium and Pleurotus. Hexanal evoked in both male and female adults extremely significant EAG responses. In behavioral assays, 3rd-instar larvae and female adults can be significantly repelled by methyl propyl disulfide, 1-octen-3-ol, or hexanal at the concentration of 100 mg/mL. Third-instar larvae and female adults were significantly attracted by limonene with a concentration of 10 and 100 mg/mL, respectively. In addition, 57 chemosensory genes, including 51 odorant binding proteins (OBPs) and 6 chemosensory proteins (CSPs), were identified...

Cyclic sulfur-containing compounds from Allium fistulosum 'Kujou'.

Sulfur-containing compounds, allicin and ajoene, etc., were isolated from Allium species. In a recent study, some sulfur-containing cyclic compounds were isolated from A. sativum, A. cepa, and A. fistulosum. Four new compounds with multiple rings with methyl disulfide or propyl disulfide at the side chain of the 7-position, kujounins A3 (1), B1 (2), B2 (3) and B3 (4), and two new thiolane type compounds with methoxy and methyl sulfoxide moiety at the 2- and 5-positions, and allium sulfoxides A2 (5) and A3 (6), were isolated from the acetone extract of the fresh white parts of Allium fistulosum 'Kujou' with three known compounds, kujounin A1 (7) and A2 (8), and allium sulfoxide A1 (9). The chemical structures of the new compounds were elucidated on the basis of physicochemical evidence. The kujounins had a rare molecular skeleton, which was tetrahydro-2H-difuro[3,2-b:2',3'-c]furan-5(5aH)-one.

Impact of Pulsed Electric Fields on the Volatile Compounds Produced in Whole Onions (Allium cepa and Allium fistulosum).

The objective of this research was to investigate the effect of pulsed electric field (PEF) processing on the volatile compounds produced in onion cultivars. The changes in the volatile compounds of onions were assessed comparing results observed while measured immediately and 24 h after PEF treatment using headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS). Significant increases in the concentrations of propanethial S-oxide, propenyl propyl thiosulfinate, 2-methyl-2-pentenal, dipropyl disulfide, propenyl propyl disulfide, methyl propyl disulfide, and methyl propenyl disulfide were observed immediately after PEF treatment. The concentrations of propenyl propyl thiosulfinate, dipropyl disulfide, methyl propyl disulfide, dipropyl trisulfide, methyl propyl trisulfide, and propenyl propyl trisulfide increased after 24 h compared to initial concentrations. It is postulated that these changes are due to PEF-induced cell permeabilisation that facilitates enzyme-substrate reactions after the PEF treatment.

Fresh and grilled eel volatile fingerprinting by e-Nose, GC-O, GC–MS and GC × GC-QTOF combined with purge and trap and solvent-assisted flavor evaporation

Fresh and grilled eel were investigated with respect to their volatile compounds and different fingerprinting techniques. An electronic nose (e-Nose) was applied to distinguish the odor between fresh and grilled eels. Purge and trap (P&T) and solvent-assisted flavor evaporation (SAFE) method were used to extract volatile compounds and further analyzed by a gas chromatographic combined with quadrupole mass spectrometry (GC–MS) and a two-dimensional gas chromatographic combined with hybrid quadrupole time-of-flight mass spectrometry (GC × GC-QTOF). SAFE extracted more ketone, alcohol and high boiling volatiles in eels than P&T. Considering some distinct compounds extracted by P&T, a P&T and SAFE combined method was chosen. There were 155 volatiles detected in fresh and grilled eels, 93 volatiles were identified. Due to the higher peak capacity, GC × GC-QTOF detected 39 compounds more than GC–MS. The key characteristic volatiles of grilled eel were methyl propyl disulfide, dimethyl trisulfide, heptane, octane, and camphene. Volatile fingerprinting can be a reference benchmark for identification and quality appraisal of fresh and grilled eel products.

FAIMS based volatile fingerprinting for real-time postharvest storage infections detection in stored potatoes and onions

Field asymmetric ion mobility spectrometry (FAIMS) was evaluated towards rapid and non-destructive detection of storage infections under varied storage conditions. Potato tubers and onion bulbs were inoculated with P. carotovorum subsp. carotovorum (causing soft rot) and B. cepacia (causing sour skin), respectively; and were incubated at room (around 25°C) and reduced temperature condition (4°C). Additional tubers and bulbs were inoculated with sterile water, which served as healthy controls. At room temperature, FAIMS could detect potato soft rot and onion sour skin pertinent volatile organic compounds (VOCs) as early as 1 and 3day(s) after inoculation (DAI) for potato tubers and onion bulbs, respectively. At a reduced temperature (4°C), the respective detection time frames were 11 and 16 DAI. Principal component analysis (PCA) based contribution analysis on FAIMS dispersion field data revealed a significant range of dispersion field (DF) intensity (52%–72%) and compensation voltage (CV) (−1.30V to −0.90V) that can potentially be used to train FAIMS for triggering an alarm during real-time monitoring of soft rot pertinent VOCs. This critical range was 47%–77% DF and −0.24V to 0.48V CV for sour skin pertinent VOCs. Naïve Bayes (NB) and linear discriminant analysis (LDA) classifiers tested on PCA datasets reported overall accuracies in the range of 71–100% and 69–100% for soft rot and 63–97% and 58–100% for sour skin, respectively. Higher accuracies were reported as days after inoculation progressed. Baseline sensing of different VOCs using FAIMS revealed that ethanol, acetone, 2-butanone and ethyl acetate were specifically contributing to P. carotovorum subsp. carotovorum caused soft rot peaks whereas pentane and 1-butanol were associated with healthy as well as inoculated tubers. Dimethyl disulfide, dipropyl disulfide, methyl propyl disulfide, undecane and 2-undecanone were found to be associated with healthy controls as well as with sour skin infected onion bulbs.

Phytosterols in onion contribute to a sensation of lingering of aroma, a koku attribute

We aimed to examine the substance in a precipitate of heat-treated onion concentrate (HOC) that contributes to a sensation of lingering of aroma, a koku attribute induced by the sensing of richness and persistence in terms of taste, aroma and texture. Adding precipitate, separated from HOC, to consommé enhanced the lingering sensation of aroma in the consommé more than adding the supernatant from HOC. After the precipitate was washed with hot water and ethanol its enhancing effect disappeared. Analysis of the HOC precipitate showed that it contained phytosterols, such as beta-sitosterol and stigmasterol. Tests of binding to aroma compounds showed that both sterols, as well as the washed precipitate, were able to bind methyl propyl disulfide and N-hexanal. Thus phytosterols in the HOC precipitate seemed to bind and hold the aroma compounds and gradually release them, inducing a lingering sensation of aroma under the koku concept during consumption.

Evaluation of insecticidal activity of the essential oil of Allium chinense G. Don and its major constituents against Liposcelis bostrychophila Badonnel

Water-distilled essential oil from the dried bulbs of Allium chinense (Liliaceae) was analyzed by gas chromatography–mass spectrometry (GC–MS). Eighteen compounds, accounting for 98.4% of the total oil, were identified and the main components of the essential oil of A. chinense were methyl allyl trisulfide (30.7%), dimethyl trisulfide (24.1%), methyl propyl disulfide (12.8%) and dimethyl disulfide (9.6%) followed by methyl allyl disulfide (3.4%) and methyl propyl trisulfide (3.6%). The essential oil exhibited contact toxicity against the booklice (Liposcelis bostrychophila) with an LC50 value of 441.8μg/cm2 while the two major constituents, dimethyl trisulfide and methyl propyl disulfide had LC50 values of 153.0μg/cm2 and 738.0μg/cm2 against the booklice, respectively. The essential oil of A. chinense possessed strong fumigant toxicity against the booklice with an LC50 value of 186.5μg/l while methyl allyl trisulfide (LC50=90.4μg/l) and dimethyl trisulfide (LC50=114.2μg/l) exhibited stronger fumigant toxicity than methyl propyl disulfide (LC50=243.4μg/l) and dimethyl disulfide (LC50=340.8μg/l) against the booklice. The results indicated that the essential oil and its major constituents have potential for development into natural insecticides or fumigants for control of insects in stored grains.

Evaluation of larvicidal activity of the essential oil of Allium macrostemon Bunge and its selected major constituent compounds against Aedes albopictus (Diptera: Culicidae).

BackgroundDuring the screening programme for new agrochemicals from Chinese medicinal herbs and local wild plants, the essential oil of dried bulbs of Allium macrostemon Bunge (Liliaceae) was found to possess larvicidal activity against mosquitoes. The aim of this research was to determine the larvicidal activity of the essential oil and its major constituent compounds against the larvae of the Culicidae mosquito, Aedes albopictus.MethodsEssential oil of A. macrostemon was obtained by hydrodistillation and analyzed by gas chromatography (GC) and gas chromaotography-mass spectrometry (GC-MS). The activity of the essential oil and its two major constituents were evaluated, using World Health Organization (WHO) procedures, against the fourth instar larvae of Ae. albopictus for 24 h and larval mortalities were recorded at various essential oil/compound concentrations ranging from 9.0 - 150 μg/ml.ResultsThe essential oil of A. macrostemon exhibited larvicidal activity against the early fourth instar larvae of Ae. albopictus with an LC50 value of 72.86 μg/ml. The two constituent compounds, dimethyl trisulfide and methyl propyl disulfide possessed strong larvicidal activity against the early fourth instar larvae of Ae. albopictus with LC50 values of 36.36 μg/ml and 86.16 μg/ml, respectively.ConclusionThe results indicated that the essential oil of A. macrostemon and its major constituents have good potential as a source for natural larvicides.

On-line mass spectrometric analysis of sulfur compounds in hydrothermal process of durian and vegetables

In this work is presented online monitoring of gasification of durian (Durio zibethinus), onion (Allium cepa L.) and garlic (Allium sativum L.) as real biomasses containing sulfuric compounds, in sub and near critical water (250, 300 and 350°C) by Lithium Ion Attachment Mass Spectrometry. Seven sulfuric compounds were detected in the resulting gas phase: H2S, ethanethiol, 1-propanethiol, methyl phenyl disulfide, propyl disulfide, diethyl trisulfide and dipropyl trisulfide gases. Allicin and alliin were successfully detected from onion and garlic samples. The effect of the subcritical conditions used on the release of sulfur heteroatomic compounds from real biomass was examined. Ca(OH)2 was adopted as an alkali reagent to suppress the emission of sulfuric compounds to the gas phase. Extraction was promoted and decomposition processes were observed for durian when Ca(OH)2 was added. For onion and garlic samples the decomposition process was prevailing with the addition of Ca(OH)2.

시판 흑양파추출액의 휘발성 향기성분

Volatile flavor compounds of 3 commercial products of black onion extract (produced in Changnyeong, Muan and Jeungpyeong) purchased in the online/offline markets were analyzed. A total of 51 compounds were detected in samples by solid phase microextraction (SPME)/GC/MSD, consisting mainly of carbonyl compounds (15), sulfur-containing compounds (8), aromatic compounds (6), furans (6), nitrogen-containing compounds (3), alcohols (2), acids (2) and miscellaneous compounds (10). Among carbonyls, 4 compounds including 2-methylbutanal, 3-methylbutanal, nonanal and benzaldehyde were detected in all samples, while two sulfur containing compounds, dimethyl disulfide and dimethyl trisulfide, were detected in high amounts and considered to be key flavors in black onion extracts. Particularly, thiophenes and 3 sulfur containing compounds (methylpropyl disulfide, methyl-(Z)-propenyl disulfide and methyl-(E)-propenyl disulfide) were detected only in two products. With acetic acid, furfural and pyrazines that formed through Maillard reaction during black onion aging were detected in high amounts in all samples. This also contributed to characteristic flavors such as roasted, sweet, and sour, in the flavor of black onion extracts.

양파추출농축액(오니웰TM)의 저장 중 휘발성 향기성분 변화

양파추출농축액(오니웰<TEX>$^{TM}$</TEX>)의 저장 유통과정 중 품질유지를 위한 척도로서 관능적요소 중 가장 중요한 휘발성 향기성분을 저장기간(<TEX>$30^{\circ}C$</TEX>, 150일) 동안 분석하였다. 총 23종의 휘발성화합물이 동정되었는데, 이는 함황 화합물류 9종, 카르보닐 화합물류 5종, 퓨란류 4종, 방향족 화합물류 2종 및 기타 화합물류 3종이었다. 함황 화합물류는 전체함량의 80.3~62.6%로 중요한 향기성분임을 알 수 있었다. 이 중 dimethyl trisulfide가 50.1~42.1% 범위로 함황 화합물류 중에서 가장 높은 함량을 차지하였다. 총 함황 화합물류의 함량은 저장기간과 함께 증가하였는데, 특히 신선한 양파향의 dimethyl disulfide와 마늘향의 methyl propyl disulfide 함량이 유의적으로 증가하였다(p<0.05). 가열반응에 의해 생성된 4종의 퓨란류(furfural, 2-acetylfuran, 5-methyl-2-furfural, furfurylalcohol)가 동정되었는데, 함량면에서 함황 화합물 다음으로 많았다(14.2~12.9%). 이 중 furfural이 전체 퓨란류의 61.9~49.4%를 차지하였고, 저장기간과 함께 유의적으로 증가하였다. 카르보닐 화합물에서는 알데히드류가 4종, 케톤 1종으로 총 5종이 검출되었다. 함량면에서는 6.2~4.8% 범위로 퓨란류 다음으로 많았으며, 가열에 의한 지방산화 분해에 의해 생성된 화합물로 동정되었다. 따라서 이들 가열반응에 의해 유도된 퓨란류나 알데히드류가 양파 특유의 함황 화합물과 함께 양파추출농축액(오니웰<TEX>$^{TM}$</TEX>)의 풍미에 기여할 것으로 추정되었다. The study was conducted to identify volatile flavor compounds in concentrated onion extracts (<TEX>$Oniwell^{TM}$</TEX>) during storage at <TEX>$30^{\circ}C$</TEX> for 150 days. A total of 23 compounds was detected in samples by solid phase microextraction (SPME)/GC/MSD, consisting mainly of 9 sulfur-containing compounds, 5 carbonyl compounds, 4 furans, 2 aromatic compounds and 3 miscellaneous compounds. The sulfur-containing compounds were major compounds with ranges of 75.8~67.3% of total volatiles. In particular, dimethyl trisulfide, with a cooked cabbage-like odor, was 50.1~42.1% of the total amount of sulfur-containing compounds. Two compounds, dimethyl disulfide (fresh garlic/green onion-like) and methylpropyl disulfide (garlic salt-like), were significantly increased with longer storage periods (p<0.05). Four furans (furfural, 2-acetylfurn, 5-methyl-2-furfural, furfurylalcohol), known as thermally generated flavors, ranged from 14.2~12.9% of total volatiles, and the amounts of 4 aldehydes (2-, 3-methylbutanal, benzaldehyde, phenylactaldehyde) derived from lipid oxidation during heat treatment were followed in that order. Accordingly, it was estimated that these 3 groups including sulfur-containing compounds, furans and aldehydes played key roles in flavors in concentrated onion extracts (<TEX>$Oniwell^{TM}$</TEX>) during storage.

초임계 이산화탄소를 이용한 살균방법이 동치미의 품질에 미치는 영향

Here we studied the changes on quality characteristics of Dongchimi by supercritical carbon dioxide to manufacture Dongchimi of high quality. There were no distinctive changes of acidity, pH, color difference, free sugar and organic acid of the Dongchimi treated with supercritical , compared to the control. The content of vitamin C in Dongchimi, which was treated with supercritical (at 25 MPa, ) was 0.826 mg/mL, and was similar to that of 0.1 MPa. Unpleasant volatile compounds such as dimethyl disulfide, metyl trisulfide and methyl propyl disulfide in Dongchimi were decreased by supercritical ; also, treatment of supercritical was useful to improve flavor of Dongchimi. Polygalacturonase activity was decreased 40.3% after supercritical carbon dioxide treatment at 25 MPa and .

Alternative Reagents for Chemical Noise Reduction in Liquid Chromatography–Mass Spectrometry Using Selective Ion–Molecule Reactions

Reduction of ionic chemical background noise based on selective gas-phase reactions with chosen neutral reagents has been proven to be a very promising approach in liquid chromatography-mass spectrometry (LC-MS). In this study further investigations on alternative reagents including the disulfides (dimethyl disulfide, diethyl disulfide, methyl propyl disulfide), dimethyl trisulfide, ethylene oxide, and butadiene monoxide, for example, have been carried out. Tandem mass spectrometric studies of ion/molecule reactions indicate that-besides dimethyl disulfide-ethylene oxide and butadiene monoxide also exhibit very efficient reactions with background ions. Furthermore, it is confirmed that the reactions are very selective according to the test with some analyte ions. In contrast to its rapid reactions with background ions, ethylene oxide does not react, or reacts much less, with these analytes. Therefore, it can be used as an alternative reagent for noise reduction. Although reactions of the other tested neutral reagents with background ions are evaluated, they are generally not suitable as reagents for this purpose because of lack of reactivity or dramatic ion losses during reactions.

Identification of Characteristic Aroma Components of Thai Fried Chili Paste

Three forms of Thai fried chili pastes (CP) were prepared, consisting of an unheated CP (UH-CP), a CP heated at 100 degrees C for 25 min (H25-CP, typical product), and a CP excessively heated for 50 min (H50-CP). The potent odorants in the CPs were investigated by two gas chromatography-olfactometry methods: dynamic headspace dilution analysis (DHDA) and aroma extract dilution analysis (AEDA). DHDA revealed that the predominant odorants in heated CPs were mainly sulfur-containing compounds, followed by lipid-derived compounds, Strecker aldehydes, and Maillard reaction products. Dimethyl sulfide, allyl mercaptan, 2- (or 3-) methylbutanal, ally methyl sulfide, 2,3-butanedione, 3,3'-thiobis(1-propene), and methyl propyl disulfide were among the most potent headspace odorants detected by DHDA. By AEDA, 2-vinyl-4 H-1,3-dithiin and diallyl trisulfide had the highest FD factors in H25-CP. On the basis of their high FD factors by both GCO methods, the predominant odorants in H25-CP were 3-vinyl-4 H-1,2-dithiin, allyl methyl disulfide, and allyl methyl trisulfide. Furthermore, dimethyl trisulfide and diallyl disulfide had the highest odor activity values in H25-CP, suggesting that these were also potent odorants in CP. In addition, methional, 3-methylbutanoic acid, 4-hydroxy-2,5-dimethyl-3-(2 H)-furanone, and 3-hydroxy-4,5-dimethyl-2( 5H)-furanone (sotolon) were indicated as potent thermally derived odorants of H25-CP.