Rapeseed oil deodorization study using the response surface methodology

Hénon, G.; Vigneron, Pierre Yves; Stoclin, Bernard; Caigniez, Joël

doi:10.1002/1438-9312(200107)103:7<467::aid-ejlt467>3.0.co;2-i

Cited by 17 publications

(14 citation statements)

References 9 publications

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“…This increase of geometrical isomers could be due to the high temperature that may have been used during deodorization (7). However, the absence of di-trans isomers (∆9t,12t) seems to indicate that a moderate temperature, probably lower than 220°C, was used (7). During the bleaching step, a temperature of 110°C is used, but this is not sufficient to produce isomerization of PUFA.…”

Section: Resultsmentioning

confidence: 99%

“…Figure 3 shows the evolution of the modified FA (trans-18:2, CLA, and cyclic FA) as a function of the percentage of polar compounds. Temperature has been shown to be the critical parameter for the formation of cyclic FA (13) and trans isomers of linoleic acids (7). Above 200°C, cyclic FA appeared, and one of the cis double bonds of linoleic acid (9cis,12cis-18:2) changed to trans, i.e., 9cis,12trans-and 9trans,12cis-18:2 (trans-18:2 in Fig.…”

Section: Resultsmentioning

confidence: 99%

“…Sunflower oil (1 L) was heated while exposed to air in a glass flask with a temperature control system. Two temperatures were used: 180°C, which corresponds to what is usually recommended for frying foods (6), and 220°C, which corresponds to a temperature giving rise to isomerization products (7). Ten heating cycles were carried out.…”

Section: Methodsmentioning

confidence: 99%

“…The amount of polar compounds was determined by HPLC on two ChromSpher Si (100 × 3 mm i.d., 5 µm, Varian, les Ulis, France) and an ELSD IIA (Varex, France). Calibration was performed with standard solutions prepared with heated rapeseed oils on which the polar compounds were carefully determined using the ISO 8420 method (7).…”

Section: Methodsmentioning

confidence: 99%

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Influence of heat and refining on formation of CLA isomers in sunflower oil

Juanéda

Pérrière

Sébédio

et al. 2003

J Americ Oil Chem Soc

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The aims of this study were to determine whether CLA are formed during refining of vegetable oils and to study the level and composition of CLA during heating. The effects of three refining steps (neutralization, bleaching, and deodorization) were analyzed with respect to their effect on CLA content. Two temperatures (180 and 220°C) were used for heating; CLA appeared only after deodorization. The level of CLA was positively influenced by temperature. More CLA were present after treatment at 220°C than at 180°C (1.3 and 0.2% of total FA, respectively). The high temperature modified the relative proportions of the CLA isomers. The main CLA isomers in fresh or heated oils were the trans,trans ones (mainly 9,11 and 10,12 isomers).Paper no. J10494 in JAOCS 80, 937-940 (September 2003).CLA is a generic term to describe isomers of linoleic acid (9cis,12cis-18:2), which contains two conjugated double bonds in positions ∆7 to ∆15 and can be in cis,cis, cis,trans, trans,cis, or trans,trans configurations. Multiple biological effects attributed to CLA isomers were recently reviewed by Pariza et al.(1). CLA are naturally present in dairy products, but they also are produced by chemical isomerizations. In dairy products, 9c,11t-18:2 represents about 80-85% of the CLA isomers (2). Commercial CLA mixtures obtained by chemical processes contain mainly 9c,11t-, 10t,12c-, 8t,10c-, and 11c,13t-18:2, accompanied by smaller quantities of 8-10, 9-11, 10-12, and 11-13 isomers in cis,cis and trans,trans configurations (3). Sébédio et al. (4) detected some CLA in sunflower oil heated under harsh conditions. CLA are also present in margarine and in partially hydrogenated vegetable oils (1) as a result of catalytic hydrogenation. More recently, the levels and structures of CLA isomers in vegetable oils collected from restaurants have been described (5). But no information indicates whether CLA are naturally present in crude oil and what the influence is of heating on the structures and the levels of CLA isomers. The aims of this study were to determine whether CLA are present in crude sunflower oil and whether any step of the refining process (neutralization, bleaching, and deodorization) induces formation of CLA isomers, and to understand the effects of heating on the level and the composition of CLA. MATERIAL AND METHODSChemicals. All solvents were distilled before use. For HPLC, acetonitrile was of UV grade (SDS, Peypin, France). The chemical reagents were obtained from Sigma (L'Isle d'Abeau, France).Samples and heating conditions. Crude and processed sunflower oil samples (neutralized, bleached, and deodorized) were obtained from a European manufacturer. Each sample was collected during the industrial processing of a single batch.Sunflower oil also was purchased in a local supermarket. Sunflower oil (1 L) was heated while exposed to air in a glass flask with a temperature control system. Two temperatures were used: 180°C, which corresponds to what is usually recommended for frying foods (6), and 220°C, which corresponds to a temperatu...

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

See 2 more Smart Citations

Influence of heat and refining on formation of CLA isomers in sunflower oil

Juanéda

Pérrière

Sébédio

et al. 2003

J Americ Oil Chem Soc

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“…Under normally applied deodorization temperatures (220-260 7C), maximum 5% of tocopherols were thermally degraded. Another mathematical model based also on the same methodology was pub-lished by Hénon et al [4]. Deodorization temperature, pressure and their interaction were the most important factors influencing the total tocopherol content in refined rapeseed oil, while the sparging steam was found to be less important in contrast to the results of De Greyt [3].…”

Section: Introductionmentioning

confidence: 98%

Tocopherol retention in physically refined rapeseed oil as a function of deodorization temperature

Čmolík

Pokorný

Réblová

et al. 2008

Euro J Lipid Sci & Tech

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The effect of deodorization temperature (between 220 and 270 7C) on tocopherol retention in physically refined rapeseed oil during deodorization in a plant-scale semi-continuous tray-type deodorizer was investigated. Among the three tocopherol homologues detected in the samples of rapeseed oils under study, the a-and g-tocopherol homologues, with the latter predominating, constituted the most abundant part of total tocopherols, accompanied by a small amount of d-tocopherol. The retention values calculated for both total and individual tocopherols decreased linearly with increasing deodorization temperature. The retention of total tocopherols decreased considerably from 91.5% at 220 7C to 54.7% at 270 7C, approaching a value of about 80% in the main area of concern between 230 and 240 7C. The retention values of individual tocopherols as well as the slopes resulting from the equations relating these retentions to deodorization temperature were observed to decrease in the same order as their molecular weights. Since the retention of a-tocopherol is slightly higher than that of g-tocopherol, the average proportion of atocopherol during deodorization slightly increases at the expense of g-tocopherol.

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