Songul Kesen

Characterization of the Key Aroma Compounds in Turkish Olive Oils from Different Geographic Origins by Application of Aroma Extract Dilution Analysis (AEDA)

The aroma and aroma-active compounds of olive oils obtained from Nizip Yaglik (NY) and Kilis Yaglik (KY) cultivars and the effect of the geographical area (southern Anatolian and Aegean regions) on these compounds were analyzed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O). For this purpose, two oil samples were obtained from their native geographical area including NY from Nizip province and KY from Kilis province (southern Anatolian region of Turkey). Another two oils of the same cultivar, NY-Bornova (NY-B) and KY-Bornova (KY-B), were obtained from the Olive Oil Research Center-Bornova, Izmir province (Aegean region of Turkey) to compare geographical effect on aroma and aroma-active compounds. Simultaneous distillation and extraction (SDE) with dichloromethane was used for extraction of volatile components. SDE gave a highly representative aromatic extract of the studied olive oil based on the sensory analysis. Totals of 61, 48, 59, and 48 aroma compounds were identified and quantified in olive oils obtained from NY, NY-B, KY, and KY-B cultivars, respectively. The results of principal component analysis (PCA) showed that the aroma profile of native region oils was discriminately different from those of Bornova region oils. Aldehydes and alcohols were qualitatively and quantitatively the most dominant volatiles in the oil samples. Aroma extract dilution analysis (AEDA) was used for the determination of aroma-active compounds of olive oils. The number of aroma-active compounds in native region oils was higher than in Bornova region oils. Within the compounds, aldehydes and alcohols were the largest aroma-active compounds in all olive oils.

Comparative Study of Bioactive Constituents in Turkish Olive Oils by LC-ESI/MS/MS

The purpose of this research was to evaluate and compare the differences in the phenolic composition, antioxidant properties, and fatty acids of virgin olive oils from the Ayvalik, Gemlik, and Memecik olive varieties cultivated in their respective growing areas over two harvest years. The phenolic composition of olive oils was carried out by liquid chromatography coupled with diode array detection and electrospray ionization mass spectrometry analysis and the fatty acid composition was determined by gas chromatography analysis. Fourteen phenolic compounds were identified and, among these, the most dominant were elenolic acid, tyrosol, and hydroxytyrosol. For olives from both years, the highest total phenolic content was determined in Memecik followed by Ayvalik and Gemlik. 2,2-diphenyl-1-picryl hydrazyl and 2,2′-azino-bis- (3-ethyl-benzothiazoline-6-sulphonic acid) methods were used to determine the antioxidant capacity of the olive oil extracts. In both methods, the antioxidant capacity values were higher for oil from cv. Ayvalik. Thirteen fatty acids were identified and quantified in all samples. Oleic acid was the highest concentration and this acid was more dominant in Gemlik oils.

Bioactive compounds and antioxidant potential in tomato pastes as affected by hot and cold break process

The effects of hot and cold break industrial tomato paste production steps on phenolic compounds, carotenoids, organic acids, hydroxy methyl furfural (HMF) and other quality parameters of tomato pastes were investigated in this study. Phenolic compounds, carotenoids, organic acids, and HMF analyses were performed with LC-DAD-ESI-MS/MS and LC-DAD-RID was used for the sugar analyses. Furthermore, the antioxidant capacities of tomato pastes were assessed via the DPPH and ABTS methods. The increase of phenol acids at the processing steps of cold break production method was higher than the hot break production method. According to PCA analyses, phenolic acids characterized cold break tomato pastes while hot break tomato pastes were characterized by flavanols and flavanones. The total amount of organic acids decreased with processing and the loss of organic acids was lower in cold break pastes. Heating and evaporation were determined as the most important processing steps in which the amount of different quality parameters change.

GC-MS olfactometric and LC-DAD-ESI-MS/MS characterization of key odorants and phenolic compounds in black dry-salted olives: Characterization of odorants and phenolic compounds in black olives

BACKGROUND Olives are processed in different ways depending on consumption habits, which vary between countries. Different de-bittering methods affect the aroma and aroma-active compounds of table olives. This study focused on analyzing the aroma and aroma-active compounds of black dry-salted olives using gas chromatography-mass spectrometry-olfactometry (GC-MS-O) techniques. RESULTS Thirty-nine volatile compounds which they have a total concentration of 29 459 µg kg-1 , were determined. Aroma extract dilution analysis (AEDA) was used to determine key aroma compounds of table olives. Based on the flavor dilution (FD) factor, the most powerful aroma-active compounds in the sample were methyl-2-methyl butyrate (tropical, sweet; FD: 512) and (Z)-3-hexenol (green, flowery; FD: 256). Phenolic compounds in table olives were also analyzed by LC-DAD-ESI-MS/MS. A total of 20 main phenolic compounds were identified and the highest content of phenolic compound was luteolin-7-glucoside (306 mg kg-1 ), followed by verbascoside (271 mg kg-1 ), oleuropein (231 mg kg-1 ), and hydroxytyrosol (3,4-DHPEA) (221 mg kg-1 ). CONCLUSION Alcohols, carboxylic acids, and lactones were qualitatively and quantitatively the dominant volatiles in black dry-salted olives. Results indicated that esters and alcohols were the major aroma-active compounds.

Characterization of Volatile Compounds of Bulgur (Antep Type) Produced from Durum Wheat

Bulgur is enjoyed and rediscovered by many people as a stable food because of its color, flavor, aroma, texture, and nutritional and economical values. There is more than one type of bulgur overall the world according to production techniques and raw materials. The volatile compounds of bulgur have not been explored yet. In this study, Headspace Solid Phase Microextraction (HS-SPME) and Gas Chromatography–Mass Spectroscopy (GS-MS) methods were used to determine the volatile flavor compounds of bulgur (Antep type, produced from Durum wheat). Approaching studies were used and the results were optimized to determine the ideal conditions for the extraction and distinguish the compounds responsible for the flavor of bulgur. Approximately, 47 and 37 important volatile compounds were determined for Durum wheat and bulgur, respectively. The study showed that there was a great diversity of volatiles in bulgur produced using Durum wheat and Antep type production method. These can lead to a better understanding of the combination of compounds that give a unique flavor with more researches.

Characterization of the key aroma compounds in tomato pastes as affected by hot and cold break process

The popular flavor of tomato and its products are primarily due to a complex mixture of acids, sugars, amino acids, minerals, and volatile compounds. Within this mixture, the aroma of tomato and its products is an important attribute that greatly influences consumer acceptability and preference. In the present study, tomato and its two types of pastes, produced from hot and cold break methods, were subject to sensory profiling, aroma, and aroma-active compounds analysis. The key aroma compounds in tomato and its two types of pastes were characterized by application of direct solvent extraction with dichloromethane/solvent assisted flavor evaporation (SAFE), gas chromatography–mass spectrometry–olfactometry (GC–MS–O) technique and aroma extract dilution analysis (AEDA). Fresh tomato and its paste volatiles were composed of alcohols, aldehydes, lactones, carboxylic acids, ketones, furans, esters, volatile phenols, 13-C norisoprenoid, terpene, and pyrrols. Via AEDA application, a total of 21 and 13 key odorants were detected in tomato and its pastes, respectively. In tomato pastes, lower numbers of aroma-active compounds than in fresh tomato were determined. The most important difference of aroma-active compounds in tomato and its pastes was hexanal, (Z)-3-hexenal, 2,3-butanediol, (Z)-3-hexenol, (E)-2-octenal, benzaldehyde, (E,Z)-2,6-nonadienal, methyl salicylate, β-ionone, 5-penthyl-2-(5H)-furanone and eugenol was not detected in tomato paste samples. On the basis of flavor dilution (FD) factors obtained by AEDA, the most powerful aroma-active compounds were (Z)-3-hexenal (FD = 512; green-grassy), 4-methyl-(5H)-furan-2-one (FD = 512; fruity), β-ionone (FD = 512; floral-violet) in tomato; 6-methyl-5-hepten-2-one (FD = 1024; green-leafy) in cold break tomato paste and furfural (FD = 512; pungent) in hot break tomato paste. In the sensory analysis, the tomato paste produced with the cold processing method was more acclaimed in terms of color, smell, taste and fruity aroma than the paste produced via the hot processing method.

Characterization of Aroma-Active Compounds in Seed Extract of Black Cumin (Nigella sativa L.) by Aroma Extract Dilution Analysis

Turkish Nigella sativa L. seed extracts were used to detect the aroma and key odorant compounds of the spice using gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Volatile compounds were extracted by the purge and trap extraction (PTE) method. A total of 32 volatile compounds consisting of different chemical classes acids (13), alcohols (7), phenols (3), terpene (1), esters (2), ketones (2), aldehyde (1), lactone (1) and hydrocarbons (2) were determined. The amounts of volatile compounds were found to be 21,544 µg kg−1. The application of aroma extract dilution analysis (AEDA) revealed the presence of 13 odor-active compounds alcohols (2), carboxylic acids (4), phenols (2), terpene (1), ketone (1), hydrocarbon (1) and unknown compounds (2) in Nigella sativa L. extract. Flavor dilution (FD) factors of key odorants ranged between 4 and 1024, while odor activity values (OAV) were in the range of 1.0 to 170.8. Acetoin was the only aroma-active ketone detected in Nigella sativa L. seed extracts. It had the strongest aroma (FD = 1024) and provided a buttery odor. This compound represented the most abundant compound of overall aroma profile with a concentration of 9394 µg kg−1, followed by isobutanoic acid (FD = 512 with a concentration of 218 µg kg−1) and contributed a powerful aroma and a cheesy characteristic odor.