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[en] As commendable as all the efforts maybe to supply our society and industry with environmental energy, they will not nearly suffice. This is most easily seen in the quantities of imported primary energy, i.e. gas and oil, and increasingly electricity too. There is an occasional flattening or a dent, but the increase is obvious. Considering the needs for more comfort, communication, mobility, it quickly becomes clear that an increase rather than a decrease is to be expected - despite all efforts to save.
[en] The rooting ability of hardwood cuttings from six selected non- edible oilferous plant species with potential for biodiesel production namely Telfairia pedata, Jatropha curcas, Excoecaria bussei, Croton macrostachyus, Croton megalocarpus and Ricinus communis was assessed on 4 different potting media i.e. forest top soil, sandy, clay and loamy soil. The proportion of cuttings that rooted were evaluated for the root numbers, root length, root dry weight, sprouting and callus formation. Complete randomized design (CRD) was adopted for the experiments and each of the species was replicated 4 times using 5 hardwood cuttings per plot (5 L capacity pots). An ANOVA was computed to test for the significance of variations between all treatments while Tukey-Kramer Multiple Comparisons test was used to test for the differences between treatment means. Jatropha curcas rooted well both in a non-mist propagator and open nursery pots, Telfairia pedata rooted only in the nursery pots, Excoecaria bussei sprouted in both non-mist propagator and open nursery pots but did not root throughout the entire experimental period of 3 months. Croton macrostachyus, Croton megalocarpus and Ricinus communis neither sprouted nor rooted calling for propagation methods other than using hardwood cuttings. Possibly all Excoecaria bussei cuttings which callused would have eventually differentiated into roots had the experiment been allowed to run for more than 3 months. (author)
[en] Density is one of the most important physical properties and its accurate measurement is important to almost all processes. Its knowledge in different temperature and pressure conditions is not only necessary in many industrial applications, but is also essential for calculating properties such as solubility or viscosity. Excess molar enthalpy represents, besides these properties, an important thermo-dynamic tool for exploring the behaviour of liquid mixtures. The thermodynamic manifestation of orientation order between vegetable oils and solutions (n-hexan) has been extensively studied from excess properties of n-hexan mixture. We have performed density measurements for all compounds up to 50 MPa int he temperature range 293-476 K. The measurements were carried out using, oils hydrostatic methods specially designed for high pressure measurements, with 0,1% accuracy. (author)
[en] This work aimed to determine the major and minor compounds of avocado oils. Mono-varietal oils from the Bacon, Fuerte, Hass, and Pinkerton cultivars were obtained by means of an Abencor® system, while commercial oils from Brazil, Chile, Ecuador and New Zealand were purchased locally. The content of triacylglycerols, fatty acids, aliphatic and terpenic alcohols, desmethyl- methyl- and dimethyl-sterols, squalene and tocopherols were determined. The main triacylglycerols were those with ECN48. In addition, the oleic, palmitic and linoleic acids prevailed. Desmethyl-sterols were the principal minor compounds. Low amounts of aliphatic and terpenic alcohols were also found. Squalene concentrations were higher in Bacon, Fuerte and Pinkerton oils than in the other oils. The most abundant tocopherol was α-tocopherol. Partial least squares discriminant analysis made it possible to express the differences among the samples. To summarize, this work brings a different approach to the complete characterization of avocado oil.
[es]El objetivo de este trabajo ha sido la determinación los componentes mayoritarios y minoritarios del aceite de aguacate. Los aceites monovarietales de las variedades Bacon, Fuerte, Hass y Pinkerton se obtuvieron mediante un sistema Abencor®, mientras que los aceites comerciales de Brasil, Chile, Ecuador y Nueva Zelanda se compraron en la localidad. Se determinó el contenido de triacilgliceroles, ácidos grasos, alcoholes alifáticos y terpénicos, desmetilmetil, metil y dimetil esteroles, escualeno y tocoferoles. Los principales triacilgliceroles fueron aquellos con ECN48. Además, prevalecieron los ácidos grasos oleico, palmítico y linoleico. Los desmetil esteroles fueron los compuestos minoritarios principales. También se encontraron bajas cantidades de alcoholes alifáticos y terpénicos. Las concentraciones de escualeno fueron más altas en los aceites de las variedades Bacon, Fuerte y Pinkerton que en las otras variedades. El tocoferol más abundante fue el α-tocoferol. El análisis discriminante de mínimos cuadrados permitió expresar las diferencias entre las muestras. En resumen, este trabajo aporta un enfoque diferente a la caracterización completa del aceite de aguacate.
[en] The topics are discussed briefly. Acrylated palm oil is prepared through acrylation process, whereby, acrylic acid is introduced into oxirane group of the EPOP (epoxidised palm oil products), EPOLA (epoxidised palm oil products acrylate) was found curable when subjected to UV (ultrviolet) light giving soft coatings. EPOLA is used as radiation curable filler/sealer, radiation curable pressure sensitive adhesives and satisfactorily be coated on wood substrates (rubberwood parquets)
[en] Capsicum annuum L. (Chipotle chili) is a natural source of bioactive metabolites with antioxidant properties. The objective of this research was to obtain and characterize the oxidative stability under storage of Chipotle chili oleoresins extracted with cold-pressed avocado oil. The most efficient conditions obtained to extract carotenoids and phenolic compounds were at 1:3 ratio (chipotle chili: avocado oil; w:v) at room temperature in darkness during 48 h. At the end of the harshest conditions (45 °C, 30 days), the extracts were stable to lipid oxidation with a final Totox value of 27.34, a carotenoid preservation of 85.6%, antioxidant activity retention of 80.66% and a color change (ΔE) of 1.783. The kinetic constants obtained were higher for peroxide formation than for carotenoid degradation. The oleoresins obtained could be considered an economic and sustainable alternative to extract carotenoids with good oxidation stability that could be used in foodstuffs.
[es]Capsicum annuum L. (chile Chipotle) es una fuente natural de metabolitos bioactivos. El objetivo de esta investigación consistió en evaluar la estabilidad oxidativa durante el almacenamiento de aceites de aguacate extraído en frio en presencia de oleorresinas de Chile Chipotle. Las condiciones más eficientes obtenidas para la extracción de carotenoides se dieron a una concentración 1:3 (p/v: chipotle chile/aceite de aguacate) durante 48 h en oscuridad a temperatura ambiente. Al final de las condiciones de almacenamiento más severas (45 °C, 30 días) los extractos fueron estables a la oxidación lipídica con un v r de Totox de 27.34, una conservación de carotenoides del 85.6%, una retención de la actividad antioxidante del 80.66% y un cambio de color (ΔE) de 1.783. Las constantes cinéticas obtenidas fueron mayores para la formación de peróxidos que en la degradación de carotenoides. En conclusión, las oleorresinas obtenidas bajo las condiciones anteriores pueden considerarse como una alternativa económica y sustentable para la extracción de carotenoides con una buena estabilidad oxidativa
[en] Surplus cereal production in the EEC and decreasing product prices, mainly for cereals, has prompted considerable interest for new earnings in arable farming. The objective was to examine whether suggested new crops (fibre, oil, medicinal and alternative grains crops) could be considered as real alternatives. Whether a specific crop can compete economically with cereals and whether there is a market demand for the crop is analyzed. The described possibilities will result in ca. 50,000 hectares of new crops. It is expected that they would not immediately provide increased earnings, but in the long run expected price developments are more positive than for cereals. The area for new crops will not solve the current surplus cereal problem as the area used for new crops is only 3% of that used for cereals. Preconditions for many new crops is further research activities and development work as well as the establishment of processing units and organizational initiatives. Presumably, it is stated, there will then be a basis for a profitable production of new crops for some farmers. (AB) (47 refs.)
[en] The worldwide expansion in the production of oil crops, the increase of the production of edible vegetable oils and of oil cake or meal in the past 50 years is presented. It is noted also that the imports of edible oil increased markedly, especially in developing countries. Plant breeding efforts have been the key to the tremendous increase in the production of oil crops. The need to devote more research and development efforts to the wide range of oil crops, to domesticate and develop species which can serve as new sources for existing or new requirements is emphasized. 9 refs, 7 tabs
[en] The aim of the present work was to evaluate the effect of rosemary extract (Rosmarinus Officinalis L.) on the 3-MCPD and glycidyl ester contents during deep-fat frying. Firstly, the potato samples were soaked in different concentrations of NaCl and they were fried in sunflower oils containing different concentrations of rosemary extract. Subsequently, repeated frying was carried out with sunflower oil enriched with rosemary extract. The frying oil and the oil extracted from potato samples were analyzed in terms of the contents of 3-MCPD and glycidyl esters according to DGF C VI 18 (10) method. The results demonstrated that the content of 3-MCPD and glycidyl esters in frying oil was not significantly affected by different NaCl and rosemary extract concentrations during short term frying; however, the amount of 3-MCPD esters was found to be lower for the potato crisps enriched with rosemary extract during repeated frying cycles.
[es]El objetivo del presente trabajo fue evaluar el efecto del extracto de romero (Rosmarinus Officinalis L.) sobre los contenidos de 3-MCPD y ésteres de glicidol durante la fritura. En primer lugar, muestras de patatas se remojaron en diferentes concentraciones de NaCl y se frieron en aceites de girasol que contienen diferentes concentraciones de extracto de romero. Posteriormente, se realizaron frituras repetidas con aceite de girasol enriquecido con extracto de romero. El aceite de fritura y el aceite extraído de las muestras de patatas se analizaron en términos de los contenidos de 3-MCPD y ésteres de glicidol de acuerdo con el método DGF C VI 18. Los resultados demostraron que el contenido de 3-MCPD y ésteres de glicidol en el aceite de fritura no se vieron afectados significativamente por las diferentes concentraciones de NaCl a corto plazo, sin embargo, la cantidad de ésteres de 3-MCPD fue menor para las patatas fritas enriquecidas con extracto de romero durante los ciclos de fritura repetidas.
[en] The aim of this work is to inform about the development of a simple and reliable off-line method for the determination of saturated hydrocarbons (SH) in vegetable oils. SH can be used as markers for fuel or for mineral oil contamination in edible oils and fats. The method consists of the isolation of the fraction by LC on deactivated silver-silica gel and subsequent on-column GC-FID analysis. This stationary phase was prepared avoiding any kind of activation. The method was developed and validated through the participation in both a proficiency test organized by the Joint Research Centre of the European Commission, and a collaborative trial carried out with trained Spanish laboratories according to the standard ISO 5725. Results showed acceptable repeatability and reproducibility values, and Horrat index, being this protocol in use with satisfactory results ever since. The method’s LOQ is 15 mg·kg–1 and its LOD 5 mg·kg–1, which make it suitable to quantify the 50 mg·kg–1 limit established by the EU, and to detect mineral oil content within the 10–500 mg·kg–1 range. Although other procedures with lower LOD have been developed throughout the years, the use of just regular laboratory equipment such as GC-FID makes the proposed method appropriate for application on a routine basis. (Author)