Distribution of Volatile Sulfur Compounds in an Interspecific Hybrid between Onion (Allium cepa L.) and Leek (Allium porrum L.)

Abstract

Volatile sulfur compounds of an interspecific hybrid between Allium cepa and Allium porrum were analyzed by gas chromatography (GC) and GC/mass spectrometry prior to isolation of the individual oils by a simultaneous distillation/extraxtion (SDE) method. Furthermore, the aroma profiles of various onion and leek cultivars were investigated. Major volatile components detected in onion were 2-methyl-2-pentenal, (E)-methyl 1-propenyl disulfide, methyl propyl trisulfide, and propanethiol, whereas dipropyl trisulfide, dipropyl disulfide, and (E)-propenyl propyl disulfide predominated in leek oils. According to the higher amount of leek chromosomes in the cell nucleus, the percentages of the measured sulfur volatiles in the hybrid material correspond more to the leek than to the onion flavor profile. Discrimination analysis was successfully applied to classify the three predefined Allium groups. It has been found that at minimum five of the most important aroma volatiles were necessary to receive sufficient differentiated clusters without any overlapping areas. This graphical display demonstrates very clearly the influence of the genetic background of the parent varieties on the sulfur volatile composition in the Allium hybrid. Keywords: Interspecific allium hybrid; onion; leek; GC analysis; volatile aroma compounds; discrimination analysis

HS-SPME-GC-MS Analysis of onion (Allium cepa L.) and shallot (Allium ascalonicum L.)

“…It is noteworthy that in previously published paper on Allium cepa L. and Allium porrum L. 2-methyl-2-pentenal was one of the main components found in the analyzed oil (Schulz et al, 1998). Probably, this observed difference depends on the extraction methodology used in the article where an aqueous blend was extracted with pentane for three hours.…”

Review. Sulfur-containing Volatile Compounds in Seafood: Occurrence, Odorant Properties and Mechanisms of Formation

“…These compounds undergo change to produce thiosulfinates which lead to polysulfides and thiosulfonates, both precursors of mono and polysulfides (Nielsen et al, 2003) (Figure 2). This pathway was put in evidence in S-containing plants such as cabbage (Chin and Lindsay, 1994), chives (Leino, 1992), leek (Schreyen et al, 1976;Nielsen et al, 2003), broccoli (Tulio et al, 2002) and onions (Schulz et al, 1998). Di-and higher sulfides are themselves reactive species and react with nucleophilic species, especially thiols, leading to disproportionation and rearrangements (Rowe, 1998).…”

Allium ampeloprasum

“…The major volatiles in leek oil were dipropyl trisulfi de, dipropyl disulfi de and ( E )-propenyl propyl disulfi de (Schulz et al 1998 ). According to the higher amount of leek chromosomes in the cell nucleus, the percentages of the measured sulfur volatiles in the interspecifi c hybrid between Allium cepa and Allium porrum material corresponded more to the leek than to the onion fl avour profi le.…”