Vegetable heating

Nishibori S and Namiki K. 1998. Superoxide anion radical-scavenging ability of fresh and heated vegetable juices. J Jpn Soc Food Sci 45(2) 144-148. 

LaBorde, L.F. and von Elbe, J.H. 1990. Zinc complex formation in heated vegetable purees. J. Agric. Food Chem. 28 437-439. 

The aroma precursors have been selected by taking into account the significant role of the Maillard reaction. Indeed, most aroma compounds of this type are formed by the reaction of amino acids with sugars or their degradation products. So we have obtained roast beef, roast mutton and heated vegetable aromas after having treated a mixture of amino acids and glucose at different temperatures and for varied times. 

Cyclic Fatty Acids in Heated Vegetable Oils Structures and Mechanisms... 

Fig.1. Monomeric cyclic fatty acids derived from heated vegetable oils l-IV, cyclic dienes from o-linolenate V-XIV, cyclic monoenes from linoleate XV-XVIll, mono-cyclic saturated acids from oleate XIX-XXII, bicyclic saturated acids from linoleate (the dotted lines indicate that the positions of the bonds within the rings were not determined) XXIII-XXVI, cyclic dienes from y-linolenate.

It has been more than 25 years since the first attempt at proposing a mechanism for formation of cyclic fatty acids in heated vegetable oils was made (27). It was proposed that the diene system in linoleic acid underwent a thermal intramolecular re-... 

Cyclic Fatty Acids In Heated Vegetable Oils... 

Dobson, G., W.W. Christie, and J.-L. Sehedio, The Nature of Cyclic Fatty Acids Formed in Heated Vegetable Oils, Grasas Aceites 4 26-33 (1996). 

B. Group II Convensional Diets with Fresh or Heated Vegetable Oil... 

The analysis of cyclopropane acids was reviewed by Minnikin (1978) and by Christie (1970), who also covered cyclopropene acids. Subsequently, Sebedio and Grandgirard (1989) discussed naturally occuring cyclic acids and cyclic acids formed in heated vegetable oils. Cyclic acids were the subject of a recent review (Le Quere and Sebedio, 1996). Useful information on gas chromatography (GC), mass spectrometry (MS) and high-pressure liquid chromatography (HPLC) of cyclic fatty acids can be found in books by Christie (1987, 1989). In the present chapter the aim is to concentrate on the more recent literature and those publications considered to be particularly... 

Cyclic fatty acids formed in heated vegetable oOs... 

Figure 5.10 Scheme for characterization of cyclic fatty acid monomers (CFAMs) from heated vegetable oils. HPLC = high-pressure liquid chromatography GC = gas chromatography FTIR = Fourier transform infra-red (spectroscopy) MS = mass spectrometry DMOX = dismethyloxazoline. 

Table 5.1 Nature and properties of monomeric cyclic fatty acids in heated vegetable oils... 

Figure 5.13 Carbon atoms involved in cyclization of A, a-linolenic acid B, linoleic acid C, oleic acid. Redrawn from Dobson, G., Christie, W. W. and Sebedio, J.-L., The nature of cyclic fatty acids formed in heated vegetable oils, Grasas y Aceites, 4, 26-33, 1996.

Cyclopentyl and cyclohexyl fatty acid monomers are present in heated vegetable oils. Sebedio et al. (1989) have used GC/MS to identify the major products from heated linseed oil as a mixture of 1 1 cis and trans cyclopentyl and cyclohexyl isomers the products of heated sunflower oil were found to be mostly cyclopentyl isomers. The major cyclopentyl isomers were the cis and trans isomers of methyl 7-(2 -hexyl cyclopentyl)-heptanoates and methyl 10-(2 -propylcyclopentyl)-decanoates. The major cyclohexyl isomers were trans and cis methyl 9-(2 -propylcyclohexyl)-nonanoates and made up 50% of the cyclic fatty acid isomers of linseed oil. Dobson et al (1995) have used AgNOs and GC/MS for the structural analysis of cyclic diene fatty acids, and Mossoba et al (1996) have presented confirmatory MS data for cyclic fatty acid monomers by using deuteration. 

Cyclic monomers have received special attention because they are considered nutritionally harmful if they are present in sufficient quantities. However, the potential harmful effects of heated fats have been controversial, because many nutritional studies have been carried out under exaggerated conditions that do not represent actual home or commercial applications (Section F). A large number of cyclic fatty acids have been identified in heated vegetable oils containing linoleic and linolenic acids. Main stmctures include disubstituted five-membered (cyclopentyl) and six-membered (cyclohexyl) compounds with... 

Heated vegetable oils Dimeric fatty acids Not toxic Perkin and Taubold (1978)... 

Dobson G., Christie W.W., Sebedio J.L. The nature of cyclic acids formed in heated vegetable oils. Grasasy Aceites, 47 26-33 (1996). 

Ng, C.-Y., X.-F. Leong, N. Masbah, S. K. Adam, Y. Kamisah, and K. Jaarin. 2014. Heated vegetable oils and cardiovascular disease risk factors. Vase. Pharmacol. 

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