The flavor profile of young shoots, flower buds, and unripe fruits of capers growing wild in Turkey

Abstract

The purpose of this study was to establish the chemical composition of the essential oils obtained from different parts such as young shoot, flower bud, and fruit of C. spinosa and C.ovata plants growing wild in Turkey. Young shoots, flower buds, and unripe fruits of caper plants were gathered from C. spinosa and C. ovata growing wild in Mersin (Mut) and Konya (Selcuklu) in Turkey in August 2003. The essential oils of all samples were hydrodistilled in portions in a circulatory Clevenger’s all glass apparatus for 4 hours. For identification of components, we used an analytical Hp 5890 gas chromatograph equipped with an FID (GC) and a DELSI 121 C apparatus fitted with a flame ionization detector and a CP WAX 51 fused silica column (25 m × 0.3 mm; 0.25 μm film thickness). Temperature was programmed from 50°C for 5 min and programmed to reach 220°C at the rate of 3°C per min. An ACP WAX 51 fused silica WCOT column (60 m × 0.3 mm) for GC/MS was used with helium as carrier gas. For GC/MS a CPWAX 52 fused silica CB column (50m × 0.25 mm) was used with helium as carrier gas (flow rate 1 mL/min) and coupled to a HP mass spectrometer: ionization energy 70 eV. Temperature programming was from 50‐240°C at the rate of 3°C/min. The samples were injected at injector temperature 240°C. The constituents of essential oils of young shoots, flower buds, and unripe fruits of Capparis spinosa var. spinosa and Capparis ovata Desf. var. canescens growing wild in Turkey were identified by GC-MS. The constituents identified in the essential oils are listed in Table 1. The yields of the essential oils of fresh young shoots, flower buds, and unripe fruits from C. spinosa and C. ovata were 0.064% and 0.081%, 0.02 % and 0.071%, and 0.075% and 0.064% (v/w), respectively. The major components in all samples were methyl isothiocyanate, octasulfur, and ethyl linoleate. Where as methyl isothiocyanate, ( E)-hexan-2-en. (Z)-hexan-3-en-1ol, and 3,4-bis(methylthio)-1,2,5-thiadiazidine are important components of young shoots of C. spinosa, methyl isothiocyanate and octasulfure were identified as major constituents of C. ovata young shoot oil. It was previously reported that the extract of C. spinosa contained methyl isothiocyanate, acetonitrile, benzaldehyde, dimethyl trisulfide, octan-3-ol, octanoic acid, cyclooctasulfure, and furfural [10]. In addition to sulfides, isothiocyanates, and other flavor molecules, elemental sulfur was identified for the first time in a non-processed food. Our results were generally similar to the literature findings with regard to the components. The observed differences are probably due to different environmental and climatological factors that can influence the oil composition.