Abstract
Cucumber and bitter gourd in the melon family are mostly salt-squeezed before cooking. Sensory tests have shown that a salt-free sample had a green note which was replaced by a mild note in a 1%-salt-squeezed sample. Aroma concentrates of salt-squeezed cucumber and bitter gourd prepared from brewed extracts were analyzed by GC-MS. Fifty-two compounds were identified as contributing to the cucumber aroma, the ratio of (E)-2,(Z)-6-nonadienal, the most important fresh cucumber aroma component, being most influenced by salt-squeezing. The salt-free sample contained higher levels of (Z)-6- nonenol and (E)-2,(Z)-6-nonadienol, while the 3%-salt-squeezed sample contained higher levels of (E)-2, (Z)-6-nonadienal, 8-nonenoic acid, and 8,11-heptadecadienal. Although the ratios of these three components and (E)-2,(Z)-6-nonadienol were lower, the ratios of (Z)-8-heptadecenal, (Z)-8,(Z)-11-heptadecadienal and (Z)-8,(Z)-11,(Z)-14-heptadecatrienal were higher in the strongly squeezed and homogenized samples. Twenty-six components containing (Z)-3-hexenol (50%) and myrtenol (16%) were identified as the characteristic aroma compounds of bitter gourd, their quantities being higher in the 1%- and 2%-saltsqueezed samples.
