Monitoring Fatty Acid and Sterol Profile of Nizip Yaglik Olive Oil Adulterated by Cotton and Sunflower Oil.

In this study virgin olive oil obtained from cv. Nizip Yaglik (NY) was adulterated with different proportions (5 and 10%, v/v) of cotton (CO) and sunflower (SO) oils. Fatty acid and sterol profiles of olive oil were analyzed by using gas chromatography (GC). Also, difference of Equivalent Carbon Number 42 values (ΔECN42) of oil samples were determined by using GC and HPLC. Due to results of fatty acids analysis, the percentage of oleic acid was decreased when CO and SO were added. Palmitic acid was increased over the addition of CO, and decreased with the addition of SO. The ΔECN42 values were increased in adulterated oils. These values showed further increase in adulterated oils with SO. Beta-sitosterols decreased to 91.06 and 88.54% when mixed with 5 and 10% SO, respectively. On the other hand, decline was negligible when mixed with CO. According to principal component analyses (PCA), pure NY and adulterated oils were clearly separated in different parts of screen plot according to fatty acids, triacylglycerol (TAGs) and sterol profile. The outcomes of this first investigation provide valuable information for about the differences of fatty acids, ΔECN42 values and sterol compounds between Turkish olive oil from Nizip Yaglik cv. and its adulteration with cotton and sunflower oil. It was observed that fatty acids are not very effective in detecting adulteration of NY oil, but ΔECN values, sterols and Rmar values can be used to detect adulteration of NY olive oil.

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.

GC-MS olfactometric and LC-DAD-ESI-MS/MS characterization of key odorants and phenolic compounds in black dry-salted 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. © 2018 Society of Chemical Industry.

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.

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.