Onion, crushed

Fiji. Oil is used externally to prevent hair loss. The oil is warmed with crushed onion and garlic and applied aurally for earache " . Water of the unripe fruit is taken orally for kidney problems " ". Ghana. Coconut milk is taken orally for diarrhea """. 

Onion oil is obtained by steam distillation of the crushed bulbs of the common onion. Allium cepa L. It is an amber-yellow to amber liquid with a strongly pungent, lasting, characteristic onion odor. 

These, like the isothiocyanates, are produced from precursors during cutting and cooking. While in the raw state, some members of this family - such as garlic and onion - exhibit on crushing... 

SH or -CH =S=0 in crushed onion is also associated with both lachrymatory and tongue tearing (itchy ) sensations. Careful evaluations of these compounds by threshold... 

Onion Oil. Obtained from crushed onion seeds, the seeds of Allium cepo L., Ltliaceae Loew, Ind. Quint. 10, 5 (1948) Phadnis er al., J. Univ. Bombay 17A, no. 24, 62... 

The volatiles from crushed neem seeds were purged with nitrogen, trapped onto Amberilte XAD-4 resin traps at room temperature, recovered and concentrated Into diethyl ether using a Kuderna-Danish evaporative concentrator at 30 "C, and analyzed by means of capillary gas chromatography/mass spectrometry (GC/MS). For comparative purposes, similar volatile concentrates were prepared from freshly chopped onion bulbs and garlic cloves, and blank controls were simultaneously prepared for each of the three test samples. 

ViRTANEN, A. I., and E. J. Matikkala The isolation of S-methyl-cysteinesulphoxide and S-n-propylcysteinesulphoxide from onion (Allium cepa) and the antibiotic activity of crushed onion. Acta Chem. Scand. 13, 1898 (1959). 

The flavor precursors, 5 -alk(en)yl-L-cysteine sulfoxides, themselves do not have any specific flavor. However, when garlic or onion cells are damaged by cutting or crushing and the 5 -alk(en)yl-L-cysteine sulfoxides meet the C-S lyase (alliinase), they are converted into various volatile sulfuric compounds. Stoll and Seebeck (1951) first proposed the production of diallyl thiosulfinate (allicin) from the 5 -allyl-L-cysteine sulfoxide (alliin) by the C-S lyase. Through the reaction catalyzed by the C-S lyase, 5 -alk(en)yl-L-cysteine sulfoxides yield alk(en)yl sulfenic acid and aminoacrylic acid, the latter being spontaneously degraded... 

Like onion, garlic is without odor until the tissues are cut or bruised, but once this occurs the odor is intensely strong and obnoxious (to some people). Garlic contains about 0.1 to 0.25% volatile constituents, formed enzymatically when garlic cloves are crushed in a manner similar to that of onion. This complex of aromatic sulfides can be recovered as so-called garlic oil by distillation. 

The lachrymating (tear-producing) principle in crushed or cut onion is thiopropanal 5-oxide (propanethial 5-oxide) produced from its precursor, tran5-5-(l-propenyl)-cpteine sulfoxide, by the action of alliinase. ... 

The Allium family includes garlic, onion, leek, and chive. All are composed of sulfur-containing character impact compounds. The aroma impact constituents of garlic are diallyl disulfide and the corresponding thiosulfinate derivative (al-licin), which are enzymatically released from a sulfoxide flavor precursor (alliin) during the crushing of garlic cloves (18). 

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