Title              : Comparison of aroma active and sulfur volatiles in three fragrant rice cultivars using GC–Olfactometry and GC–PFPD 

Researcher       : Kanjana Mahattanatawee*, Russell L. Rouseff

Department     : *Food Technology Department, Faculty of Science, Siam University

E-mail                : *kanjana@siam.edu

Abstract   : Aroma volatiles from three cooked fragrant rice types (Jasmine, Basmati and Jasmati) were characterised and identified using SPME GC–O, GC–PFPD and confirmed using GC–MS. A total of 26, 23, and 22 aroma active volatiles were observed in Jasmine, Basmati and Jasmati cooked rice samples. 2-Acetyl-1-pyrroline was aroma active in all three rice types, but the sulphur-based, cooked rice character impact volatile, 2-acetyl-2-thiazoline was aroma active only in Jasmine rice. Five additional sulphur volatiles were found to have aroma activity: dimethyl sulphide, 3-methyl-2-butene-1-thiol, 2-methyl-3-furanthiol, dimethyl trisulphide, and methional. Other newly-reported aroma active rice volatiles were geranyl acetate, β-damascone, β-damascenone, and ɑ-ionone, contributing nutty, sweet floral attributes to the aroma of cooked aromatic rice. The first two principal components from the principal component analysis of sulphur volatiles explained 60% of the variance. PC1 separated Basmati from the other two cultivars and PC2 completely separated Jasmine from Jasmati cultivars.

Keywords: PCA, Cooked rice, Headspace SPME

Link to Publication: Food Chemistry/ in Sopus

Bibliography     :    Mahattanatawee, K., & Rouseff, R. L.(2014). Comparison of aroma active and sulfur volatiles in three fragrant rice cultivars using GC–Olfactometry and GC–PFPD. Food Chemistry, 154, 1-6.

Title              :  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 

Researcher       : Kanjana Mahattanatawee, Torsak Luanphaisarnnont, Russell Rouseff

Department     : Food Technology Department, Faculty of Science, Siam University

E-mail                : kanjana@siam.edu

Abstract   : 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.

Link to Publication: Journal of Agricultural and Food Chemistry, Vol.66 Issue 10 March 2018

Bibliography     :    Mahattanatawee, K., Luanphaisarnnont, T., & Rouseff R. (2018). 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. Journal of Agricultural and Food Chemistry, 66(10), 2480-2484.