Quantitative Silver Ion Thin Layer Chromatography of Triacylglycerols from Sunflower Oils Differing in the Level of Linoleic Acid

Long echo time proton magnetic resonance spectroscopy for estimating relative measures of lipid unsaturation at 3 T

“…The olefinic/methylene peak area ratio and diallylic/methylene peak area ratio was calculated for all the oils from the TE = 200 msec spectra. The outcomes were compared with approximated mean values for number of olefinic/methylene protons and number of diallylic/methylene protons determined from compositions in the literature for almond (33, 34), canola or rapeseed (24, 35), cod liver (24), corn (35, 36), linseed (24, 35, 37, 38), peanut or groundnut (24, 35, 37), sesame (24, 35, 37), mid‐oleic sunflower (24, 35, 39), and walnut oil (24, 34, 35). The experimental values correlated well with deductions from the literature as shown in Fig.…”

Silver Ion TLC of Minor Triacylglycerol Components for Unambiguous Detection of Adulteration of Olive Oil With Vegetable Oils

“…Under the first set of conditions the TAG classes from S 3 to M 2 D are separated, while the most unsaturated classes (from SD 2 to T 3 ), which contained two and more dienoic and=or trienoic FA residues remain unseparated, grouped into one or more peaks expressed as a percentage of the total (denoted as Sum of the Polyunsaturated TAG (SPUTAG), depending on the oil. [18,[20][21][22] The second set of conditions is used to completely separate the individual components of the SPUTAG group. In olive oil these are minor components (SD 2 , MD 2 , SMT, M 2 T, D 3 , MDT and SDT), which are measured as part of SPUTAG (assumed to be 100%).…”

“…After analyzing a series of sunflower oils with decreasing content of linoleic acid, it was found that oils with down to 50% linoleic acid have a TAG composition, characteristical of typical sunflower oil. [22] We divided the studied virgin olive oils, according to their linoleic acid content, into three types, assigned as low linoleic olive oil, LLOO (<6% linoleic acid), typical olive oil, TOO (6-10% linoleic), and high linoleic olive oil, HLOO (>10% linoleic acid). [18] The mean content of SPUTAG was 4.5 AE 0.5 for LLOO, 6.2 AE 0.3 for TOO, and 12.1 AE 0.7 for HLOO.…”

“…Still, identification can be made by a characteristic marker: for cotton -SD 2 , for sunflower -D 3 , and for soy -D 2 T. In Table 3 the SPUTAG profile of the three types of olive oil and the four adulterants are compared with the SPUTAG components of eight sunflower oils with decreasing content of linoleic acid, which we analyzed in a previous study. [22] At low levels of adulteration, Sun1 to Sun4 oils will act as typical sunflower oils, Sun5 and Sun6 oils will cause change similar to that of corn oil. The linoleic acid content of samples Sun7 and Sun8 makes them similar to TOO and HLOO, respectively.…”

“…Strangely, the ECN42 value of corn oil was higher than that of sunflower oil, which indicates the occasional choice of the studied oils -typically sunflower oil has higher ECN42 than corn oil. [19] The aim of this work was, on the basis of the procedure recently developed in our laboratory for quantitative Ag-TLC analysis of highly unsaturated TAG classes in virgin olive oils [18] and common seed oils [20][21][22] to propose an analytical approach for unambiguous detection of adulteration of olive oil with most common vegetable oils. The variations in the TAG composition of samples caused by the natural variation of the component FA were considered, with special attention concentrated to the differences between olive oils with different linoleic acid content, in order to avoid erroneous assessment of sample's authenticity.…”