Structure indices in FA chemistry. How relevant is the iodine value?

  title={Structure indices in FA chemistry. How relevant is the iodine value?},
  author={Gerhard Knothe},
  journal={Journal of the American Oil Chemists' Society},
  • G. Knothe
  • Published 1 September 2002
  • Chemistry
  • Journal of the American Oil Chemists' Society
Most common analytical methods in FA chemistry can be categorized as yielding either structure or quality indices. Quality indices often describe components in fats and oils arising from processing, storage, and naturally occurring, nonfatty materials. Common structure indices are the iodine value (IV), the saponification value, and the hydroxyl value. Although modern analytical methods yield more detailed and reliable information, structure indices are still widely used. The IV, which… Expand

Figures and Tables from this paper

Dependence of oil stability index of fatty compounds on their structure and concentration and presence of metals
During storage and use, vegetable oil-derived industrial products such as biodiesel and biodegradable lubricants can be subjected to conditions that promote oxidation of their unsaturated components.Expand
Potentiometric Titration as an Alternative Technique for the Determination of the Iodine Value in Biodiesel Matrix from Palm Oil
The specification of biodiesel is related to factors associated with its quality as a fuel. The iodine value as one of those quality parameters measures the degree of unsaturation present in aExpand
Oxidative Stability of Commodity Fats and Oils: Modeling Based on Fatty Acid Composition
Although fatty acid (FA) composition is known to be of fundamental importance to oxidative stability in lipids, consistent quantifications of the magnitude of this association have proved elusive.Expand
Graphical method to select vegetable oils as potential feedstock for biodiesel production
Chemical compositions of 80 vegetable oils were collected from literature and the properties of the obtainable biodiesel (methyl esters) have been predicted by empirical relationships. The purposeExpand
Simultaneous determination of six quality parameters of biodiesel through 1H NMR spectroscopy and partial least squares.
Hydrogen nuclear magnetic resonance (1H NMR) spectra were used to build multivariate models, from partial least squares (PLS), in order to perform simultaneous determination of six important quality parameters of biodiesel, significantly reducing analysis time, reagent and solvent consumption, and waste generation. Expand
Analyzing biodiesel: standards and other methods
Biodiesel occupies a prominent position among the alternatives to conventional petrodiesel fuel owing to various technical and economic factors. It is obtained by reacting the parent vegetable oil orExpand
Qualitative and quantitative analysis of the influence of biodiesel fatty acid methyl esters on iodine value
A preliminary conclusion is that biodiesel with a low percentage of both long-chain saturated and poly-unsaturated FAMEs can have solidifying point (SP) and OS in the proper range and is generally more combustible and efficient. Expand
Correlation between the chemical structure of biodiesel and its physical properties
Biodiesel is a renewable, biodegradable, environmentally benign, energy efficient, substitution fuel which can fulfill energy security needs without sacrificing engine’s operational performance. ThusExpand
Utilization of Cuttlefish Liver Waste for Oil Production: Evaluation of Quality Characteristics and Biological Activity
The ash, moisture, protein and carbohydrate content of the extracted oil were estimated as 4, 7, 4 and 1% respectively. The Vitamins A and E was found to be 59.14 and 17.4 mg/100 g. Nine fatty acidsExpand
5 – Analytical Methods
Publisher Summary Biodiesel is produced by transesterifying the parent oil or fat with an alcohol, usually methanol, in presence of a catalyst, usually a strong base such as sodium or potassiumExpand


Oxidative stability index of vegetable oils in binary mixtures with meadowfoam oil
Abstract The oxidative stability indices (OSI) of several vegetable oils were determined at 110°C. Meadowfoam oil, Limnanthes alba, was found to be the most stable oil with an OSI time of 67.3 h forExpand
Evaluating the oxidation stability of biodiesel. An experimental contribution
In this paper procedures and results obtained during the oxidation stability evaluation of biodiesel samples prepared from different vegetable oils, having a wide range of fatty acid composition andExpand
The Lipid handbook
Fatty acid structure. Lipid structure. Occurrence and characteristics of oils and fats. Separation and isolation procedures. Processing of fats and oils. Analytical methods. Synthesis. PhysicalExpand
Technical Performance of Vegetable Oil Methyl Esters With a High Iodine Number
The Federal Institute of Agricultural Engineering in Austria has been gaining more experience about the technical performance of biodiesel with a high iodine number. Long term tests were carried outExpand
The iodine number and the unsaturation number of fats
SummaryIn order to determine the degree of unsaturation of fats and to study the kinetics of their hydrogenation, it is proposed to use instead of the iodine number an index which is called theExpand
The effects of vegetable oil properties on injection and combustion in two different diesel engines
Four different vegetable oils, each in at least 3 different stages of processing, have been characterized according to their physical and chemical properties, their injection and atomizationExpand
Jojoba oil analysis by high pressure liquid chromatography and gas chromatography/mass spectrometry
Two analytical procedures for determining com-positions of jojoba liquid wax esters are described and compared. One, the more tedious, involves separation of wax ester homologs by high pressureExpand
A study of the effect of chemical structure on friction and wear: Part 2: Vegetable oils and esters
This paper continues the study of the effect of chemical structure on friction and wear characteristics of base stocks in the four-ball wear tester. The study compares friction and wear properties ofExpand
Biodiesel: the use of vegetable oils and their derivatives as alternative diesel fuels.
Vegetable oils and their derivatives (especially methyl esters), commonly referred to as {open_quotes}biodiesel{close_quotes}, are prominent candidates as alternative diesel fuels. They have advancedExpand
Injector-fouling propensity of certain vegetable oils and derivatives as fuels for diesel engines
The results of experiments specifically designed to study the propensity for certain vegetable oil candidates as fuels to foul the injectors of representative farm-type diesel engines are presented.Expand