In the present study, neutral oil loss (distillative and mechanical carry-over) during physical refining of coconut oil was quantified. Neutral oil loss seems to depend on both the crude oil quality and the process conditions during deodorization. The distillation of volatile glyceridic components (monoand diglycerides), originally present in the crude oil, was confirmed as the major cause for the neutral oil loss. The amount of these volatile components in crude coconut oils cannot be derived as such from the initial free fatty acid content. A lower deodorization pressure with less sparge steam resulted in a larger neutral oil loss than a higher pressure with more steam. A "deodorizability" test on a laboratory scale under standardized conditions (temperature = 230°C, pressure = 3 mbar, time = 60 min, sparge steam = 1%), to evaluate crude oil quality and to obtain a more accurate prediction of the expected neutral oil loss and free fatty acid content in the fatty acid distillate, is described.

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The aim of this study was to determine whether substituting enzymatically interesterified butter for native butter in the usual diet affects lipid and lipoprotein levels in man. Parameters studied were serum total cholesterol, LDL-cholesterol, HDL-cholesterol, free cholesterol, phospholipids, triglycerides, apoA1 and apoB and the fatty acid composition of serum triglycerides, free fatty acids, phospholipids and cholesterol esters. Subjects were healthy volunteers and a controlled design was used. The only mathematically significant difference found when interesterified butter was substituted for butter was an about 7% lower fraction of oleic acid in the serum cholesterol esters (p = 0.005). In contrast to an earlier study where chemically interesterified butter fat was substituted for native butter, no indications are found in this study that replacing native butter by enzymatically interesterified butter, in amounts normally consumed, may have any beneficial effect on health.

High‐pressure size‐exclusion chromatography (HPSEC) was used in combination with column chromatography on silica to determine the polymeric and oxidized triglyceride content of 19 refined vegetable oil samples of different origin (corn, sun, soy, peanut, rapeseed, palm and olive oil). The evolution of these compounds during the labscale physical refining of corn oil was also studied. Dimeric and oxidized triglyceride levels of the refined oils ranged between 0.32–2.01% (mean = 1.07%) and 1.53–4.83% (mean = 3.11%), respectively. A major increase of polymeric triglycerides was observed during the deacidification‐deodorization step, while the oxidized triglycerides increased mainly during bleaching. Further studies to determine the exact influence of refining conditions on the formation of polymeric and oxidized triglycerides are necessary.

Analyse von Tocopherolen mittels Gas-Flüssigkeits-und Hochleistungsflüssigchromatographie: eine vergleichende Untersuchung. Ausgewählte Normalphasen-HPLC-und gaschromatographische Methoden wurden für die Analyse von Tocopherolen in pflanzlichen Ölen untersucht. Wiederholbarkeit, Genauigkeit und/oder Wiederfindung wurden für beide Methoden bestimmt und mit Daten der offiziellen Methodik verglichen. Die größte Genauigkeit wurde mittels der Normalphasen-HPLC-Technik, basierend auf der AOCS-Methode Ce 8-89, erzielt, was wahrscheinlich durch die kurze und einfache Probenaufbereitung erklärt werden kann. Es wurden Tocopherolgehalte von sechzehn voll raffinierten Pflanzenölen mit sowohl GLC als auch HPLC bestimmt. Die Regressionsanalyse zeigte, daß Tocopherolgehalte, die mittels GLC ermittelt worden sind, um 6,1% höher waren als die vergleichbaren HPLC-Daten. Obwohl die ermittelte Wiederfindungsrate der GLC-Methode gut ist, scheint es, daß bei der Probenaufbereitung zusätzlich eine Auftrennung mittels Dünnschichtchromatographie eingeführt werden sollte, um eine Überlappung der Peaks zwischen Tocopherolen und einigen störenden Substanzen der unverseifbaren Fraktion zu vermeiden.a Department of Food Technology and Nutrition, University of Ghent, Gent, Belgium. b De Smet Engineering N. V., Edegem, Belgium.vents and reagents used were analytical or HPLC grade and purchased from Acros Organics (Geel, Belgium). Gas liquid chromatographySample preparation: The selected GLC procedure was based on the AOCS official method Ce 3-74 [6]. 5-7 g of oil were saponified in the presence of 0.15 % butylhydroxytoluene as antioxidant [5]. Tocopherols and sterols were not separated by thin-layer chromatography prior to GLC analysis. Derivatization was accomplished by the addition of 1 ml acetic acid anhydride, keeping the mixture 10 min at 140 °C. After cooling, 1 µl was injected in the gas chromatograph.Gas-chromatographic conditions: Analyses were carried out on a Carlo Erba 4160 chromatograph equipped with a flame-ionization detector (FID) and a split injector (split ratio 1:40) (Carlo Erba, Milano, Italy). A fused silica capillary column coated with a nonpolar stationary phase (CP TM Sil 5CB, 25 m × 0.25 mm internal diameter; 0.25 µm film thickness, Chrompack, The Netherlands) was selected. The oven temperature was kept constant at 290 °C. Injector and detector were maintained at 340 °C. All tocopherol homologues eluted within 15 min. The total analysis time was set at 30 min to assure the elution of all sterols.Identification of the individual tocopherols was realized with pure standards as reference compounds.Quantification: Correction factors were determined for all tocopherols by analyzing different mixtures of the tocopherol standards and an internal standard (3-octadecyloxy-1,2-propanediol). Quantitative analyses were performed with a Shimadzu RC3A integrator. High-performance liquid chromatographyPrinciple: The selected NP-HPLC procedure was based on the previously mentioned IUPAC method 2.432 [5] and the AOCS official method Ce ...