Additional neutral volatiles from litchi ( Litchi chinensis sonn.) fruit

Odor volatiles in three major lychee cultivars (Mauritius, Brewster, and Hak Ip) were examined using gas chromatography-olfactometry, gas chromatography-mass spectrometry, and gas chromatography-pulsed flame photometric detection. Fifty-nine odor-active compounds were observed including 11 peaks, which were associated with sulfur detector responses. Eight sulfur volatiles were identified as follows: hydrogen sulfide, dimethyl sulfide, diethyl disulfide, 2-acetyl-2-thiazoline, 2-methyl thiazole, 2,4-dithiopentane, dimethyl trisulfide, and methional. Mauritius contained 25% and Brewster contained 81% as much total sulfur volatiles as Hak Ip. Cultivars were evaluated using eight odor attributes: floral, honey, green/woody, tropical fruit, peach/apricot, citrus, cabbage, and garlic. Major odor differences in cabbage and garlic attributes correlated with cultivar sulfur volatile composition. The 24 odor volatiles common to all three cultivars were acetaldehyde, ethanol, ethyl-3-methylbutanoate, diethyl disulfide, 2-methyl thiazole, 1-octen-3-one, cis-rose oxide, hexanol, dimethyl trisulfide, alpha-thujone, methional, 2-ethyl hexanol, citronellal, (E)-2-nonenal, linalool, octanol, (E,Z)-2,6-nonadienal, menthol, 2-acetyl-2-thiazoline, (E,E)-2,4-nonadienal, beta-damascenone, 2-phenylethanol, beta-ionone, and 4-vinyl-guaiacol.

Section: Resultsmentioning

confidence: 91%

“…Other investigators (3,4) have described its odor/aroma as sweet, rose-floral, and citrus-like. Previous studies identified many of the free or neutral volatiles in this fruit (3)(4)(5)(6). Johnston and co-workers (3) identified 42 volatiles in freshly macerated lychee from Florida.…”

Section: Introductionmentioning

confidence: 97%

Comparison of Three Lychee Cultivar Odor Profiles Using Gas Chromatography−Olfactometry and Gas Chromatography−Sulfur Detection

Mahattanatawee

Pérez‐Cacho

Davenport

et al. 2007

“…Johnston et al (1980) were the first to report on the volatiles of lychee, suggesting the citrus flavor was due to the presence of compounds such as geranial and neral and its floral note was due mainly to 2-phenylethanol. Two other papers, subsequently published, reported headspace and neutral volatiles in this fruit (Toulemonde and Beauverd, 1985;Froehlich and Schreier, 1986). Among the volatiles identified, limonene, rose oxide, nonanal, decanal, citronellol, and geraniol were considered to be significant for the fruityfloral and citrus notes of the fruit.…”

Section: Introductionmentioning

confidence: 81%

Gas Chromatography/Olfactory Analysis of Lychee (Litchi chinesis Sonn.)

Ong

Acree

1998

102

Volatile compounds from lychee (Litchi chinesis Sonn.), a tropical fruit native to China, were extracted using both Freon 113 and ethyl acetate solvents. The odor-active compounds present in the fruit were isolated and characterized using gas chromatography/olfactory (GC/O), chromatography, and mass spectrometry. Authentic standards were used to determine mass spectral, retention index, and odor match. GC/O analysis detected at least 60 odor-active volatiles in the fruit extract. More odor-active volatiles were detected in the ethyl acetate extract than in the nonpolar Freon extract. Among the compounds that had significant odor activity, geraniol, guaiacol, vanillin, 2-acetyl-2-thiazoline, 2-phenylethanol, unknown (58), (Z)-2-nonenal, β-damascenone, 1-octen-3-ol, Furaneol, and linalool were found to be the most odor-active. On the basis of their calculated odor activity values (OAV), isobutyl acetate, guaiacol, cis-rose oxide, 2-acetyl-2-thiazoline, β-damascenone, Furaneol, linalool, (E)-2-nonenal, geraniol, and isovaleric acid were determined to significantly contribute to the aroma of this fruit. GC/O analysis confirmed that 2-phenylethanol was probably responsible for the floral character and that the citrus-fruity aroma is due to the presence of many odor-active terpenes, particularly geraniol. Although cis-rose oxide was only 30% as active in GC/O as the most potent odor, its high OAV indicates its importance to the character of lychee odor. An unknown sesquiterpene-like compound (58), with a lychee-like odor characteristic of the fresh fruit, was identified by GC/O as being a highly odor potent compound. Taken together, the aroma of lychee was determined to be due to the interaction between compounds with floral, nutty, citrus, and fruity aromas. Keywords: Aroma; GC/O; lychee; volatiles

“…Several previous studies have explored the volatile composition of fresh litchi fruit, as well as frozen litchi , , dried litchi , and canned litchi . However, some of these researches did not cover the cultivar of litchi ,, , and some investigated only a few cultivars ,,, or only performed qualitative identification of volatiles . It remains unclear which volatile components are similar and which are unique, and what the volatile profile characters are among different commercially cultivated litchi cultivars.…”

Section: Introductionmentioning

confidence: 99%

Comparison of Volatile Profiles of Nine Litchi (Litchi chinensisSonn.) Cultivars from Southern China

Wu¹,

Pan²,

Qu³

et al. 2009

Volatile components of nine litchi cultivars (10 samples) with high commercial value from Southern China were investigated by means of gas chromatography-mass spectrometry combined with headspace solid phase microextraction. A total of 96 volatiles were detected, of which 43 were identified. Seventeen common volatiles in all the samples included linalool, cis-rose oxide, alpha-terpineol, beta-citronellol, geraniol, p-cymene, ethanol, 3-methyl-3-buten-1-ol, 3-methyl-2-buten-1-ol, 1-hexanol, (E)-2-hexen-1-ol, 2-ethyl-1-hexanol, 1-octen-3-ol, 1-octanol, ethyl acetate, p,alpha-dimethylstyrene and 3-tert-butyl-4-hydroxyanisole. Although the volatile composition and concentration varied between these cultivars, the components with the highest OAVs in most cultivars were still cis-rose oxide, trans-rose oxide, 1-octen-3-ol, and geraniol. Two Huaizhi samples from two producing areas exhibited similar volatile profiles, and significantly different from other cultivars according to cluster analysis performed on amounts of major volatile components.