Identification of Characteristic Aroma Components of Thai Fried Chili Paste

Abstract

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.

Characterization of potent odorants in Thai chempedak fruit (Artocarpus integer Merr.), an exotic fruit of Southeast Asia

“…The solvent phase was separated by centrifugation at 1200 ×g for 30 min. Volatile and non-volatile compounds were separated from the pooled supernatant using solvent assisted flavor evaporation (SAFE) according to the procedure described by Engel, Bahr, and Schieberle (1999) and Rotsatchakul, Chaiseri, and Cadwallader (2008). Briefly, this technique is operated by connecting a compact and distillation vessel for rapid and high yields isolation of volatile from solvent extracts.…”

“…The column effluent was split at the ratio of 1:5 between the FID and the sniffing port using fused silica tubing with moist air supplied. The final temperature of both detectors was held at 250°C (Cadwallader, Potts, Brisske-be Vier, & Mirarefi, 2011;Rotsatchakul et al, 2008).…”

“…The mass spectrometric data was collected from m/z 35 to 350 amu at a scan rate of 5.27 scan/s. Ionization voltage was 70 eV (Rotsatchakul et al, 2008).…”

“…Duplicate analyses were performed, and the average values were reported. The concentration was calculated according to Rotsatchakul et al (2008) as following:…”

Detection of poultry spoilage markers from headspace analysis with cryoadsorption on a short alumina PLOT column

“…Interestingly, this compound has also been identified in melon, strawberry, passion fruit, onions, cheese, beer, wine, whiskey, coffee, and cooked meats, and is used as a flavouring agent (IPCS INCHEM, 2001;Yannai, 2004). Allyl methyl sulphide is a reported antioxidant found in chopped garlic and has also been identified by other groups in the headspace above Thai fried chili pastes (Amorati & Pedulli, 2008;Lawson & Gardner, 2005;Rotsatchakul, Chaiseri, & Cadwallader, 2008). Thus, whilst methyl thiolacetate and allyl methyl sulphide occur naturally in some foods, these compounds, in addition to the other potential marker compounds identified, may still be indicators for chicken spoilage.…”