scholarly journals Changes of free fatty acids during ripening of Niva cheese

2004 ◽  
Vol 22 (SI - Chem. Reactions in Foods V) ◽  
pp. S310-S313
Author(s):  
E. Vítová ◽  
J. Zemanová ◽  
Š. Bezděková ◽  
L. Babák ◽  
B. Loupancová ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Sample Preparation ◽  
Free Fatty Acids ◽  
Acid Content ◽  
Potassium Hydroxide ◽  
Methyl Esters ◽  
Flame Ionization Detection ◽  
Ripening Period ◽  
Flame Ionization

Changes in the concentrations of free fatty acids in Niva cheese were monitored over the ripening period. Fatty acids were analyzed as methyl esters using gas chromatography with flame ionization detection. Identification has been carried out by comparison of the retention times with those of standard substances. Methanol esterification method using potassium hydroxide catalysis was used for preparing the sample of the fatty acids. The method is simple in respect to instrumentation and chemicals. It can be applied directly to the cheese matrix, which significantly decreases the time for sample preparation. There were total of 30 fatty acids identified in the cheese. Capric, myristic, palmitic, stearic and oleic acids represented the largest proportion of acid content and the most significant changes during ripening.

scholarly journals Evaluation of Major Fatty Acids Determination in Palm Oil by Gas Chromatography-Flame Ionization Detection

2016 ◽  
Vol 36 (03) ◽  
pp. 308 ◽  
Author(s):  
Moh Taufik ◽  
Hanifah Nuryani Lioe ◽  
Nancy Dewi Yuliana
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Fatty Acid ◽  
Palm Oil ◽  
Methyl Esters ◽  
Coefficient Of Determination ◽  
Flame Ionization Detection ◽  
Ionization Detection ◽  
Flame Ionization ◽  
Fatty Acids Analysis

The fatty acid composition of palm oil is the major factor influencing its physical and chemical properties. The purpose of this research was to evaluate the analytical performance of major fatty acids (palmitic acid, stearic acid, oleic acid, and linoleic acid) analysis in palm oil. Triglycerides of palm oil were derivatized to fatty acid methyl esters (FAMEs) by using boron trifluoride (BF3) in methanol. FAMEs were determined by gas chromatography-flame ionization detection (GC-FID) using DB-23 capillary column as stationary phase. The studied parameters were instrument performance analysis, the efficiency of fatty acid derivatization, stability of derivatized analytes, accuracy, repeatability, intra-lab reproducibility, ruggedness, and method uncertainty. The evaluation results showed the instrument linearity at a working range of 5 to 40 mg/mL marked by coefficient of determination (R2) between 0.991-0.995. Instrument limits of detection (LOD) and instrument limits of quantification (LOQ) for 4 major fatty acids analysis were 26-35 µg/mLand 86-128 µg/mL, respectively. The increase of fatty acid concentration led to the decrease of derivatization efficiency in the fatty acids analysis. The result also showed that derivatized analytes were stable during 24 h storage at freeze temperature. The average recovery values by spiking method with the spiking concentration at 50 and 90 mg/g sample were at 75-94 % for stearic and linoleic acids analysis, however those for palmitic and oleic acids analysis were considered very low (<40 %), due to their low derivatization efficiency. Repeatability and intra-lab reproducibility of 4 major fatty acids analysis were at acceptable ranges, 0.45-1.38 % and 1.15-2.03 %, respectively. Determination by varying the volume of derivatizing agent showed the rugged method. Uncertainty of repeatability (Ur) and uncertainty of reproducibility (Ur) were ranged at 1.84-9.02 mg/g and 1.40-10.65 mg/g, respectively. This method was considerably reliable for the analysis of less abundance fatty acids in palm oil, stearic and linoleic acids.

Determination of selected fatty acids in dried sweat spot using gas chromatography with flame ionization detection

2016 ◽  
Vol 39 (22) ◽  
pp. 4377-4383 ◽  
Author(s):  
Roman Kanďár ◽  
Petra Drábková ◽  
Lenka Andrlová ◽  
Adam Kostelník ◽  
Alexander Čegan
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Flame Ionization Detection ◽  
Ionization Detection ◽  
Flame Ionization

Changes in free fatty acids during the ripening of Idiazabal cheese: influence of brining time and smoking

1994 ◽  
Vol 61 (2) ◽  
pp. 281-288 ◽  
Author(s):  
Ana I. Nájera ◽  
Luis J. R. Barron ◽  
Yolanda Barcina
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Free Fatty Acid ◽  
Free Fatty Acids ◽  
Free Fatty Acid Content ◽  
Acid Content ◽  
Lipolytic Activity ◽  
Fatty Acid Content ◽  
Ripening Period ◽  
Cheese Ripening

SummaryThe effect of brining time and smoking on the free fatty acid content of Idiazabal cheese during ripening was examined. The main free fatty acids considered underwent at least some increase during the first stage of ripening before day 90 and tended to level off around a constant value towards the end of the ripening period. There were significant differences in free fatty acid levels during ripening among cheeses with different brining times and between smoked and unsmoked cheeses. Brining time and smoking exerted marked effects on lipolytic activity during cheese ripening, depending upon the free fatty acid involved and ripening time. In general, brining and smoking led to increases in free fatty acid levels at the end of the ripening period; the different behaviour of butyric acid may be due to a specific lipolytic activity.

Development of headspace–gas chromatography–flame ionization detection procedure to determine volatile fatty acids in zoo organic waste leachates

2011 ◽  
Vol 63 (12) ◽  
pp. 2873-2877 ◽  
Author(s):  
Anna Banel ◽  
Marta Wasielewska ◽  
Monika Felchner-Żwirełło ◽  
Bogdan Zygmunt
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Organic Waste ◽  
Volatile Fatty Acids ◽  
Sample Introduction ◽  
Flame Ionization Detection ◽  
Monocarboxylic Acids ◽  
Ionization Detection ◽  
Flame Ionization ◽  
Headspace Gas

In order to determine volatile fatty acids (short chain monocarboxylic acids with 2 to 6 carbon atoms in a molecule) in leachates formed in organic waste piles a procedure based on static headspace (HS) coupled with gas chromatography (GC) have been proposed and optimized. The conditions of HS extraction and sample introduction into a gas chromatograph as well as of chromatographic separation were considered. Using flame ionization detection LODs were of the order of 0.02– 0.37 mg/L. The analyzed leachate collecting on and close to a zoo organic waste pile contained VFAs (Volatile Fatty Acids) at a concentration ranging from 5.5 mg/L to 0.88 g/L and from below LOD to 10.1 mg/L for pool water at some distance from the pile, respectively.

scholarly journals DETERMINATION OF FATTY ACIDS IN SOLANUM SURATTENSE BURM. F. BY USING GAS CHROMATOGRAPHY

2017 ◽  
Vol 10 (8) ◽  
pp. 60 ◽  
Author(s):  
Raman Preet ◽  
Raghbir Chand Gupta
Keyword(s):  
Fatty Acids ◽  
Gas Chromatography ◽  
Fatty Acid ◽  
Methyl Esters ◽  
Basic Research ◽  
Fatty Acid Analysis ◽  
Operating Conditions ◽  
Solanum Surattense ◽  
Flame Ionization

  Objective: This study aims to document the fatty acid composition of Solanum surattense Burm. f. collected from hot desert of India, Rajasthan.Methods: The fatty acid analysis was performed by gas chromatography-flame ionization detector (GC-FID). The operating conditions used to examine methyl esters of fatty acids are as follows. Fatty acids were converted into methyl esters (FAMEs) before GC analysis according to the standard methods by Ranganna (1986). Quantitative determinations of FAMEs were conducted using GC-FID and capillary column HP-88 Agilent Technologies.Results: The most abundant fatty was palmitic acid (13.2%), oleic acid (22.9%), and linoleic acid (11.9%). This plant is good source of important fatty acids including all the groups of saturated, monounsaturated, and polyunsaturated fatty acids (MUFAs and PUFAs) and can be used as a commercial source of fatty acids especially MUFAs and PUFAs.Conclusion: The plant is well studied for various pharmacological activities such as antiasthmatic, anticancer, cardiovascular, and hepatoprotective. Determination of fatty acid profiles in nutritional and clinical research with precision and fastness has become popular for human health and basic research.

scholarly journals Composition Characterization of Fatty Acid Zinc Salts by Chromatographic and NMR Spectroscopic Analyses on Their Fatty Acid Methyl Esters

2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Kwang Seo Park ◽  
Yun Ju Kim ◽  
Eun Kyung Choe
Keyword(s):  
Mass Spectrometry ◽  
Fatty Acids ◽  
Gas Chromatography ◽  
Fatty Acid ◽  
Free Fatty Acids ◽  
Fatty Acid Methyl Esters ◽  
Methyl Esters ◽  
Gas Chromatography Mass Spectrometry ◽  
Acid Methyl ◽  
Zinc Salts

To implement EU REACH- (Registration, Evaluation, and Authorization of Chemicals-) like chemical legislations in various countries of which the purpose is human and environment safety, the first step is substance identification followed by the hazard and risk assessments. Although both structural and composition identifications are required, the latter can more importantly result in the essential data to fill out the required substance information such as purity and concentrations of constituents, as well as impurities. With fatty acid zinc salts (FAZSs) as an exemplary industrial chemical of which chromatographic and nuclear magnetic resonance (NMR) analyses were impossible due to their insolubility in water and any organic solvents, the composition characterization was tried by preparing their fatty acid methyl esters (FAMEs) using the conc. HCl/methanol/toluene method. This acid-catalyzed methyl esterification was optimized with zinc stearate as a surrogate substance. Gas chromatography-mass spectrometry (GC-MS) and NMR analyses on methyl-esterified products revealed that the optimum conditions were at 90°C for 10 min or 45°C for 30 min with two equivalent HCl as well as at 45°C for 10 min with five equivalent HCl. Almost all zinc stearates were converted into the corresponding fatty acids with 97–99% conversion rates. Free fatty acids (FFAs) were detected in extracted ion chromatograms of pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) in the methyl-esterified products with incomplete conversions of 73∼79%. The optimized conc. HCl/methanol/toluene method of direct one-step reaction from FAZSs was compared with the two-step NaOH saponification/BF3-methanol method after acidic hydrolysis of FAZSs. The mechanism of fatty acid zinc salts into free fatty acids and fatty acid methyl esters was suggested with the evidence of the formation of Zn(OH)2.

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