Journal of the American Oil Chemists' Society

The influence of the oxidation level on the phase transition behavior of sunflower oil was evaluated by differential scanning calorimetry (DSC) and synchrotron X-ray diffraction (XRD) at both small and wide angles. The crystallization was monitored at a cooling/heating rate of 2 °C/min from 20 to −80 °C and vice versa applying both techniques. The triacylglycerols organize in two double-chain length structures: α 2L (61.87 Å) and β′ 2L (82.89 Å). The crystalline structure changes upon oxidation. In particular, the intensity of the XRD peak associated with the double-chain structure of β′, as well as its crystallization and melting enthalpy, significantly decreases as the oxidation level increases.

The sardine canning industry produces vast quantities of effluents that need expensive reprocessing. Their oily component contains valuable n−3 polyunsaturated fatty acids, namely EPA (5,8,11,14,17-eicosapentaenoic acid) and DHA (7,10,13, 16,19-docosahexaenoic acid), up to 10% each. Our aim was to develop a process allowing the recovery of these fatty acids. After removing solid particles, proteins, and peptides from the crude effluent, the obtained oil was hydrolyzed. EPA and DHA were enriched from the recovered free fatty acid fraction by selective enzymatic esterification. Lipases were used as biocatalysts: LipozymeTM allowed up to 80% DHA enrichment but gave no EPA enrichment. By immobilizing Candida rugosa lipase on Amberlite IRC50 cation-exchange resin, a 30% EPA enrichment was obtained.

Extract of purple sunflower hulls is a potential red food colorant; however, suitable process conditions must still be identified. Selected process variables were studied using bench-scale units to prepare, clarify, concentrate and spray dry extracts. Concentration by evaporation at 32°C and addition of maltodextrin to 15% (wt/dry wt) prior to drying largely eliminated pigment degradation during those steps. Relative to water extracts, extracts prepared with 5 to 15% ethanol in water generally yielded more pigment with similar levels of degradation and loss during subsequent processing. Use of 5% ethanol/2% citric acid reduced yield by about half relative to water, but gave a powder with a lower degradation index and wetting time. Percentage recovery of pigment during concentration and drying was not greatly affected by solvent type or extraction temperature.

Triglyceride compounds isolated from jojoba seed oil by column chromatography were composed predominantly of C18′ C20′ C22′ and C24 n−9 fatty acids with minor amounts of saturated C16. Chain length and double-bond positions were determined by gas-liquid chromatography and gas-liquid chromatography-mass spectrometry of the corresponding methyl ester and picolinyl ester derivatives. Triglyceride structures were analyzed directly by ion trap mass spectrometry. The analysis of minor compounds, can provide highly specific information about the identity of an oil.

As much as 20% of soil humus occurs in the form of lipids. High values are characteristic of Podzol soils and highmoor peats. Lipids of the following types are known to be present: paraffin hydrocarbons, phospholipids, fats, waxes, fatty acids, and terpenoids. A long list of compounds have been reported; the identification of many of them require confirmation using modern analytical techniques. Some of the lipids known to occur in soil have phytotoxic properties; these may have a depressing effect on seed germination and on root and shoot growth. Waxes and similar materials may be responsible for the difficultly wettable condition of certain sands.