Feral Temelli

Bio: Feral Temelli is an academic researcher from University of Alberta. The author has contributed to research in topics: Supercritical fluid & Supercritical carbon dioxide. The author has an hindex of 47, co-authored 174 publications receiving 6483 citations. Previous affiliations of Feral Temelli include Autonomous University of Barcelona.

Microencapsulation of flax oil with zein using spray and freeze drying

Abstract: Microencapsulation of flax oil was investigated using zein as the coating material. Central Composite Design – Face Centered was used to optimize the microencapsulation with respect to zein concentration ( x 1 ) and flax oil concentration ( x 2 ) using spray drying. Also, freeze drying was carried out at two zein:oil ratios. The quality of microcapsules was evaluated by determining encapsulation efficiency, flowing properties (Hausner ratio), and evaluating the morphology with scanning electron microscopy. The response surface model for microencapsulation efficiency showed a high coefficient of determination ( R 2 = 0.992) and a non-significant lack of fit ( p = 0.256). The maximum microencapsulation efficiencies were 93.26 ± 0.95 and 59.63 ± 0.36% for spray drying and freeze drying, respectively. However, microcapsules prepared by spray and freeze drying had very poor handling properties based on the Hausner ratio. The bulk density decreased with an increase in zein concentration at the same flax oil concentration. The morphology of the flax oil microcapsules depended on the zein:flax oil ratio and the process used for microencapsulation. Flax oil microcapsules prepared by spray drying appeared to be composed of heterogeneous spheres of various sizes at high zein:flax oil ratios. Microcapsules prepared by freeze drying resulted in agglomerated small spheres. These microcapsules might find a niche as functional food ingredients.

Perspectives on supercritical fluid processing of fats and oils

Abstract: Over the past two decades, fats and oils processing using supercritical carbon dioxide (SC-CO2) has developed from focusing only on extraction to fractionation of complex lipid mixtures, conducting reactions in supercritical fluid media and particle formation techniques for the delivery of bioactive lipid components. Extraction of specialty oils and column fractionation of deodorizer distillates to concentrate tocopherols have reached commercial scale. Even though significant progress has been made in fundamental aspects, many challenges lie ahead to better understand the phase behavior and solubility of multicomponent lipid mixtures in SC-CO2 and to generate the much needed fundamental data, including transport properties, density and interfacial tension. Considering the increasing consumer demand for “natural” products and stricter government regulations on the use of organic solvents like hexane, the future of SC-CO2 processing of lipids is bright. Based on the know-how accumulated, integrated processes can be developed, targeting ingredients for both food and non-food industrial applications, which would fit well into a larger biorefinery approach.

Supercritical carbon dioxide extraction of carotenoids from carrot using canola oil as a continuous co-solvent

Abstract: The “natural” food colorants, carotenoids, are of great importance to human health. In an effort to enhance the efficiency of SC-CO 2 extraction of carotenoids from carrots, canola oil was investigated as a continuous co-solvent. The carotenoid content of the starting material was determined by traditional solvent extraction (TSE). Carrot samples with different particle size and moisture content were extracted with SC-CO 2 at different temperature, pressure, canola oil concentration and CO 2 flow rate for 4 h. Carotenoids were identified and quantified by HPLC analysis. α-Carotene, β-carotene, and lutein were the main carotenoids in the extracts. When canola oil was added as a co-solvent, the α- and β-carotene yields were improved more than twice and lutein yield was more than four times higher compared to those obtained with SC-CO 2 extraction alone. Both increasing temperature and increasing pressure had significant positive effects on the carotene yields except for that of lutein. Larger particle size had a negative effect on carotenoid yields. The α- and β-carotene yields decreased with moisture while the lutein yield increased. Higher carotenoid yields were achieved after 4 h of extraction at higher flow rate, while more carotenoids were solubilized in SC-CO 2 at lower flow rate. The highest carotenoid yields were obtained at 70 °C, 55.1 MPa, 5% canola oil concentration (w/w of CO 2 ), 0.25–0.5 mm particle size, 0.8% moisture content of feed material, and 2 L/min CO 2 flow rate. Employing canola oil as a continuous co-solvent in SC-CO 2 extraction is a novel and efficient technique for the recovery of carotenoids from natural materials.

Thermochemical biofuel production in hydrothermal media: A review of sub- and supercritical water technologies

Abstract: Hydrothermal technologies are broadly defined as chemical and physical transformations in high-temperature (200–600 °C), high-pressure (5–40 MPa) liquid or supercritical water. This thermochemical means of reforming biomass may have energetic advantages, since, when water is heated at high pressures a phase change to steam is avoided which avoids large enthalpic energy penalties. Biological chemicals undergo a range of reactions, including dehydration and decarboxylation reactions, which are influenced by the temperature, pressure, concentration, and presence of homogeneous or heterogeneous catalysts. Several biomass hydrothermal conversion processes are in development or demonstration. Liquefaction processes are generally lower temperature (200–400 °C) reactions which produce liquid products, often called “bio-oil” or “bio-crude”. Gasification processes generally take place at higher temperatures (400–700 °C) and can produce methane or hydrogen gases in high yields.

Bioactive compounds in seaweed: functional food applications and legislation

Abstract: Seaweed is more than the wrap that keeps rice together in sushi. Seaweed biomass is already used for a wide range of other products in food, including stabilising agents. Biorefineries with seaweed as feedstock are attracting worldwide interest and include low-volume, high value-added products and vice versa. Scientific research on bioactive compounds in seaweed usually takes place on just a few species and compounds. This paper reviews worldwide research on bioactive compounds, mainly of nine genera or species of seaweed, which are also available in European temperate Atlantic waters, i.e. Laminaria sp., Fucus sp., Ascophyllum nodosum, Chondrus crispus, Porphyra sp., Ulva sp., Sargassum sp., Gracilaria sp. and Palmaria palmata. In addition, Undaria pinnatifida is included in this review as this is globally one of the most commonly produced, investigated and available species. Fewer examples of other species abundant worldwide have also been included. This review will supply fundamental information for biorefineries in Atlantic Europe using seaweed as feedstock. Preliminary selection of one or several candidate seaweed species will be possible based on the summary tables and previous research described in this review. This applies either to the choice of high value-added bioactive products to be exploited in an available species or to the choice of seaweed species when a bioactive compound is desired. Data are presented in tables with species, effect and test organism (if present) with examples of uses to enhance comparisons. In addition, scientific experiments performed on seaweed used as animal feed are presented, and EU, US and Japanese legislation on functional foods is reviewed.