bluuebunny/crossref_metadata_2025 huggingface dataset:
Orthodox Diaspora and Mission in South Africa
Authors: Hayes Stephen
Published: November 2010

The Orthodox diaspora has, paradoxically, spread Orthodox Christianity throughout the world, but has not contributed much to Orthodox mission. Even after the third or fourth generation of immigrants, church services are generally held in the language of the countries from which the immigrants came. This is certainly true of South Africa, where most of the Orthodox immigration has been from Greece and Cyprus, with smaller groups of Russians, Serbs, Bulgarians, Lebanese and Romanians. Though there were immigrants from these countries in southern Africa in the middle of the nineteenth century, it was only at the beginning of the twentieth century that Orthodox clergy arrived and churches were built, first in Cape Town and then in Johannesburg. It was only in the twenty-first century that clergy began to be ordained locally in any numbers. The churches therefore tended to be ethnic enclaves, and apathetic towards, or even opposed to, mission and outreach to other ethnic communities.
Geostatistics for Mapping Leaf Area Index over a Cropland Landscape: Efficiency Sampling Assessment
Authors: Martinez Beatriz , Cassiraga Eduardo , Camacho Fernando , Garcia-Haro Javier
Published: November 2010

This paper evaluates the performance of spatial methods to estimate leaf area index (LAI) fields from ground-based measurements at high-spatial resolution over a cropland landscape. Three geostatistical model variants of the kriging technique, the ordinary kriging (OK), the collocated cokriging (CKC) and kriging with an external drift (KED) are used. The study focused on the influence of the spatial sampling protocol, auxiliary information, and spatial resolution in the estimates. The main advantage of these models lies in the possibility of considering the spatial dependence of the data and, in the case of the KED and CKC, the auxiliary information for each location used for prediction purposes. A high-resolution NDVI image computed from SPOT TOA reflectance data is used as an auxiliary variable in LAI predictions. The CKC and KED predictions have proven the relevance of the auxiliary information to reproduce the spatial pattern at local scales, proving the KED model to be the best estimator when a non-stationary trend is observed. Advantages and limitations of the methods in LAI field predictions for two systematic and two stratified spatial samplings are discussed for high (20 m), medium (300 m) and coarse (1 km) spatial scales. The KED has exhibited the best observed local accuracy for all the spatial samplings. Meanwhile, the OK model provides comparable results when a well stratified sampling scheme is considered by land cover.
DEM Development from Ground-Based LiDAR Data: A Method to Remove Non-Surface Objects
Authors: Sharma Maneesh , Paige Ginger B. , Miller Scott N.
Published: November 2010

Topography and land cover characteristics can have significant effects on infiltration, runoff, and erosion processes on watersheds. The ability to model the timing and routing of surface water and erosion is affected by the resolution of the digital elevation model (DEM). High resolution ground-based Light Detecting and Ranging (LiDAR) technology can be used to collect detailed topographic and land cover characteristic data. In this study, a method was developed to remove vegetation from ground-based LiDAR data to create high resolution DEMs. Research was conducted on intensively studied rainfall–runoff plots on the USDA-ARS Walnut Gulch Experimental Watershed in Southeast Arizona. LiDAR data were used to generate 1 cm resolution digital surface models (DSM) for 5 plots. DSMs created directly from LiDAR data contain non-surface objects such as vegetation cover. A vegetation removal method was developed which used a slope threshold and a focal mean filter method to remove vegetation and create bare earth DEMs. The method was validated on a synthetic plot, where rocks and vegetation were added incrementally. Results of the validation showed a vertical error of ±7.5 mm in the final DEM.
Halide exchanged Hoveyda-type complexes in olefin metathesis
Authors: Wappel Julia , Urbina-Blanco César A , Abbas Mudassar , Albering Jörg H , Saf Robert , Nolan Steven P , Slugovc Christian
Published: November 2010

The aims of this contribution are to present a straightforward synthesis of 2nd generation Hoveyda-type olefin metathesis catalysts bearing bromo and iodo ligands, and to disclose the subtle influence of the different anionic co-ligands on the catalytic performance of the complexes in ring opening metathesis polymerisation, ring closing metathesis, enyne cycloisomerisation and cross metathesis reactions.
Cross-metathesis of allylcarboranes with O-allylcyclodextrins
Authors: Šnajdr Ivan , Janoušek Zbyněk , Jindřich Jindřich , Kotora Martin
Published: November 2010

Cross-metathesis between allylcarboranes and O-allylcyclodextrins was catalyzed by Hoveyda–Grubbs 2nd generation catalyst in toluene. The corresponding carboranyl-cyclodextrin conjugates were isolated in 15–25% yields.
Physico-chemical studies concerning miscelies of vegetable oils XIV. Molar volume, molar refraction and viscosity for methyl stearate solutions in cyclohexane, hexane, tetrachloroethylene or trichloroethylene
Authors: Muñoz Cueto María J. , Galán Vallejo M. , Flores Luque V.
Published: November 2010

In the miscelies studied, molar volume and molar refraction values show linear dependence with the molar fraction of methyl stearate.
Viscosity values fit Hildebrand's modified equation, where the "Vo" parameter is a linear function of the molar fraction of methyl stearate.
Regarding with this three physico-chemical properties, the mixtures studied behave like ideal mixtures of two organic liquids without ionization.
Epoxidation of refined soy-bean oil by molecular oxygen. Influence of the variables. Kinetic study
Authors: Martínez de la Cuesta P. J. , Rus Martínez E. , Román Cortés V.
Published: November 2010

The influences of temperature, concentration of catalyst and initial concentration of unsaturation on epoxide formation and esters from oleic and linoleic acids disappearance in liquid phase epoxidation reaction by molecular oxygen of soy-bean oil using molibdenyl-acetylacetonate as catalyst, has been studied.
From experimental data obtained by a complex factorial design, an equation for epoxide formation reaction rate as a function of temperature, catalyst concentration and unsaturation initial concentration were deduced.
A kinetic model is proposed too and using a calculation program based on 4th Order Runge-Kutta numerical procedure to simulate the reactions that took place, the kinetic coefficients and activation energies that best fitted the calculated data to the experimental data were determined.
Alimentation Influence in the characteristics of compounds related with fat of ham from iberic pigs
Authors: Melgar J. , Cid C. , Astiasarán I. , Bello J.
Published: November 2010

Alimentation influence (acorn, acorn-bait mixed, bait) over characteristics fat and their degradation products, that are in part, responsible of the aroma of ham, has been studied. Influence over the naturation degree has been observed. Relation oleic/linoleic+linolenic acids are different In the three types of hams. Also water activity, salinity index and redox potential show differences that affect to the relative percentage of satured and unsatured free fatty acids. Fat of bait hams suffer more oxidation. Acorn and mixed acornbait hams offer a higher level of pentanal and acetaldehyde. Whereas bait hams have higher level of hexanal, heptanal and octanal. The percentage of cetonic compounds are similar in all then.
Influence of microwave heating on the stability of processed samn
Authors: Farag Radwan S. , Taha Soad H.
Published: November 2010

Butter was converted to samn by microwave and conventional heating. The quality of the processed samn by the two methods was followed by determining the acid, peroxide and TBA values over a period of six weeks at 60°C. The fatty acid composition of samn samples was determined by gas-liquid chromatographic technique. The data show that butter conversion to samn by microwave heating was accomplished in about one half of the time that conventional heating requires. Microwave heating obviously increased the development of samn rancidity compared with the conventional heating. The parameters used for measuring lipid rancidity indicated that the main cause of samn rancidity under the present conditions is an oxidation mechanism.
Assays for physical refining of shea butter
Authors: Ruiz Méndez M. V. , Huesa Lope J. , Pereda J. , Dobarganes M. C.
Published: November 2010

Assays for physical refining of shea butter.
The best conditions for the refining of shea butter used-in cosmetic industries are defined. The objective is to obtain a bleached, deodorized fat, with a 3% maximum free acidity and a high amount of unsaponifiable matter having minimal losses with respect to the initial sample.
The following variables have been studied: phosphoric acid proportion in degumming, bleaching clays and active carbon percentages in bleaching, and temperature/time in the stage of deodorization.
The results demonstrate that good quality shea butter can be obtained by physical refining if the level of free fatty acid in the initial sample is lower than 5%. Otherwise, a neutralization is necessary, which should be partial in order to reduce the loss of unsaponifiable matter.
Composition and oil characteristics of apricot, peach and cherry kernel
Authors: Lazos Evangelos S.
Published: November 2010

Se han obtenido huesos de albaricoque, melocotón y cereza de vegetales procesados y se han separado y analizado las pepitas después de eliminar las cascaras. El aceite crudo, extraído con éter de petróleo, fue 38’4, 48’0 y 26’0% de materia seca de pepitas de albaricoque, melocotón y cereza respectivamente; el contenido en proteina cruda fue 21’2, 26’7 y 25'3%; fibra bruta 5'0, 5’4 y 9’5%; hidratos de carbono totales 32'4, 16'0 y 34’5% de los cuales 9’3, 7’1 y 11’3% fueron azúcares reductores: y ceniza 3’0, 4’0 y 4’6% respectivamente. Se han encontrado en las pepitas cantidades considerables de K, P, Mg y Ca; se han tabulado valores para 15 minerales. Las características del aceite fueron: índice de iodo 105, 97, 116; índice de saponificación 195, 201, 198; materia insaponificable 0’95, 1’60, 3’12%; índice de refracción (40°C) 1’4635, 1’4622, 1’4693; y gravedad específica (20°C) 0’9227, 0’9158, 0’9419 para aceite de pepita de albaricoque, melocotón y cereza respectivamente. El ácido graso dominante fue el oleico (68’0, 69’0, 46’0% respectivamente) seguido por el linoleico (24’2, 22’0, 41’6% respectivamente). Se han encontrado también en concentraciones traza C12:0, C14:0, C14:1, C15:0, C15:1, C16:0, C16:1, C17:0, C17:1, C18:0, C18:3, C20:0 y C20:1. El esterol principal fue el β-sitosterol alcanzando alrededor del 90%, seguido por el campesterol. Se han encontrado asimismo colesterol, estigmasterol, Δ5-avenasterol. Δ7-estigmasterol y Δ7-avenasterol.
Characterization of foods merging relational and lineal decision rules. An application to virgin olive oil of Malaga
Authors: Aparicio R. , Ferreiro L. , Rodríguez J. L.
Published: November 2010

The chemical compounds of a food, quantified by GC, can be used to build relational and lineal decision rules, which merged by mathematical algorithms, could allow its characterization.
The paper describes the methods applied to design and evaluate those rules, which are kept in the knowledge base of a deductive expert system, and the procedure applied to know the similarity between an unidentified sample and the food defined by the rules.
The characterization of virgin olive oil of Malaga province has been used to explain the methodology. Thus, 54 chemical compounds belonging to five different series, fatty acids, methylsterols, sterols, aliphatic and triterpernic alcohols, and aliphatic and terpenic hydrocarbons, besides a group composed by a hydroxi-aldehid-triterpenic, phytol, and erytrodiol, were identified and quantified in each of the 172 samples collected over Andalusia. Their chromatograms, which were redrawn by computers, allowed to build seventeen rules among lineal and relational ones. These relational rules (10) show linguistic interrelations, such less, great, equal, etc., among two or more chemical compounds of the same or different series. On the other hand, statistical programs of discriminant analysis allowed to get the lineal rules (7) whose coefficients were taken from each one of the series, plus a rule where they were reached in the whole set of chemical compounds.
Finally, twenty-six samples collected in different zones, provinces or countries, or in the same area but from different crops, were used to measure the performance of the methodology.
Changes in white tuna (Thunnus alalunga) fat due to cannig process and storage preserve
Authors: García Arias María T. , Castrillón A. María , Navarro María P.
Published: November 2010

Modifications in fatty acid composition in white tuna (Thunnus alalunga) ocurring at each stage of the cannig process, boiling and sterilization in soybean oil, were studied. Boiling was performed in brine and two sterilization times (55 and 90 minutes) as well as the effects of storage for one year were tested. Boiling had no effect on fatty acid composition or the n-3/n-6 ratio. However canned tuna absorbed soybean oil during sterilization, causing an increase of the percentage of C18:1, C18:2 and C18:3 and a decrease in C20:5 and C22:6. Therefore, unsaturated fatty acids to saturated fatty acids (PS/S) ratio changed and the n-3/n-6 ratio declined from 7.03 to 0.59 compared with raw tuna. Due to the whole fat enrichment, canned fish showed a slight loss of PUFA (C20:5 and C22:6) and a increase of C18:1, C18:2 and C18:3. The latter effect was more marked in the preserves as a consequence of one year storage. The convenience of using for cannig an oil containing a lower amount of polyunsaturated fatty acid in order to remain the original n-3/n-6 ratio of the raw tuna is discussed.
A comparative study on the deterioration of oils by microwave and conventional heating
Authors: Parag Radwan S. , Hewedi Fawzy M. , Abo-Raya Salah H. , El-Baroty Gamal S. A.
Published: November 2010

Refined cottonseed oil and hydrogenated palm oil were heated by two methods, i.e., conventionally by gas-cooker and microwaves. Quality assurance methods such as refractive index, color, diene content, acid value, peroxide value, TBA value, iodine value, petroleum ether insoluble oxidized fatty acid content and degree of polymerization were determined. Exposing the oil samples to various heating times and microwave oven power caused some hydrolysis to free fatty acids, accelerated the formation of hydroperoxides and secondary oxidation products. The values from each test increased with both the power settings of microware oven and time of heating. In general, the development of rancidity for refined cottonseed oil heated by microwaves was twice faster than that produced by conventional heating. Also, the chemical values for refined cottonseed oil were much higher than that of hydrogenated palm oil in all cases.
Evaluation of date kernel oils and their effects on wheat flour characteristics
Authors: Elsakr A. S.
Published: November 2010

Date kernels constitute about 13% of the whole date fruit, and cotain moderate amounts of oils with relatively high caloric values. Agwa soft and Aprimi dry date kernel oils were used in this work. Results showed that Aprimi date kernel oils have high levels of both caproic acid and stearic acid of 23.04 and 18.40% respectively, while Agwa kernel oils have high levels of caprylic acid and capric acid of 22.31 and 12.20%. Moreover Agwa oils achieved higher amounts of unsaponifiable matters, sterols and tocopherols.
The addition of soft and dry date kernel oils did not improve the wheat flour strength but raised its resistance to extensibility.
Biochemical changes of lipids in plant foods and feeds. II. Lipid hydroperoxides metabolism
Authors: Zamora R. , Hidalgo F. J. , Alaiz M.
Published: November 2010

The enzymes of the lipoxygenase pathway in plant foods are reviewed. This part analyzes the enzymes related to the descomposition or transformation of the lipidic hydroperoxides. Lipoxygenase, hydroperoxide lyase, enal isomerase, alcohol dehydrogenase, aldehyde dehydrogenase, hydroperoxide dehydrase, alene oxide ciclase and 12-Oxo-phytodienoic acid reductase in plants are described. Posible control mechanisms of the lipoxygenase pathway are also considered.
Instrumental methods for NaCl analysis in olive brines
Authors: García García P. , Brenes Balbuena M. , Garrido Fernández A.
Published: November 2010

Aplicability of flame photometric and ion selective (sodium or chloride) methods to determinate NaCI concentration in olive brines in comparison with the official one (Volhard), which uses AgNO3, is studied.
According to the results using standard solutions or fermentative olive brines without previous lye treatment, no proportional systematic or constant systematic errors are detected and the percentaje of NaCl is evaluated by them with the same accuracy as by the reference. However, when the flame photometric or sodium ion-selective methods are used to determine this compound in Spanish olive brines, there is a deviation in comparison with the values obtained by the official one (Volhard) that is correlated with the combine acidity concentration of the solution. This fact is due to the presence of sodium organic salts, called combined acidity, that are formed during the lye treatment or "cocido" that these fruits are given before fermentation. Nevertheless, is does not represent any problem as there is a good correlation between such combined acidity and the magnitude of the deviation, that permit to calculate the corresponding correction factor. In addition these problems can be solved using the chloride selective ion method.
Transesterification of fatty acid esters with arylaminoalcohols. Synthesis of mono- and diacylderivatives of 3-phenylamino- 1,2-propanediol
Authors: Gómez Gómez R. , Vázquez Roncero A.
Published: November 2010

In this paper the synthesis of acylderivatives of 3-phenylamino- 1,2 propanediol has been studied. These compounds are prepared by transesterification of fatty acids methyl esters with the amino-alcohol and sodium methoxide as catalyst. The reaction was carried out with mechanical stirring under vacuum.
The effect of temperature, molar relation of reactives, time and concentration of catalyst on the reaction yield has been investigated. Yield increases with temperature and ester concentration until the optimun reaction temperature is reached.
This temperature depend on molar relation ester/aminoalcohol (140 °C for 1/1 and 2/1 values and 120 °C for 4/1 value).
The composition of reaction mixture was evaluated from the mono/di relation. This relation decrease when temperature and molar relation increase.
Preparation and characterization of fibre fractions in olives (Hojiblanca, var.)
Authors: Guillén R. , Heredia A. , Felizón B. , Jiménez A. , Fernández Bolaños J.
Published: November 2010

Acid detergent fibre (ADF), neutral detergent fibre (NDF), insoluble fibre (IF) and soluble fibre (SF) were isolated from the flesh of Hojiblanca variety fresh green olives.
Composition and recovery of polysaccharides, expressed as neutral sugars content, were studied for each one of these fractions.
Variation of the quality parameters of sunflower grain and oil (H. annus) stored at different relative environmental humidities
Authors: Motta A. , Eguiazu G. M.
Published: November 2010

Commercial samples of sunflower were exposed to different relative humidities (75%, 80%, 84%, 92% and 98%) for two months. In addition to the kinetic rehydratation in standard and treated samples, the following parameters were measured: humidity, fat content, germinative power, acidity index, iodine number and fatty acids composition.
Fatty acids composition, iodine number and fat content, did not change significantly. Only the acidity index and the germinative power were an index of the damage.
Dynamic viscoelasticity of commercial mayonnaise: influence of temperature and oil content
Authors: Berjano M. , Gallegos C.
Published: November 2010

The linear dynamic viscoelasticity of two commercial foodstuffs, oil in water emulsions with very different oil contents, has been studied. Temperature ranged between 10 and 40°C. From the experimental results it can be deduced that less oil content produces a significant decrease in the linear viscoelastic functions, as well as an enhanced temperature sensitivity.
A regression analysis on the green olives debittering
Authors: Kopsidas Gerassimos C.
Published: November 2010

In this paper, a regression model, which gives the debittering time t as a function of the sodium hydroxide concentration 0 and the debittering temperature T, at the debittering of medium size green olive fruit of the Conservolea variety, is fitted. This model has the simple form t=aoCa1 ∙ ea2/T, where ao, a1, and a2 are constants. The values of ao, a1, and a2 are determined by the method of least squares from a set of experimental data. The determined model is very satisfactory for the conditions in which Greek green olives are debittered.
Correlation among fat, reducing sugars and moisture contents in the fresh pulp of olives
Authors: Sánchez Gómez A. H. , Fernández Díez M. J.
Published: November 2010

Statistical analysis of the results obtained for fat, reducing sugars, and moisture, in the fresh pulp of olives from two Spanish varieties, Gordal and Zorzaleña, and one of Greek origin, Conservolea, during the growth and ripening period, gives rise to a multiple regression equation, which is valid for the three considered varieties.
No significant differences, related to variety, crop, and culture region, were found in this study.
Thin layer chromatographic detection of some common antioxidants
Authors: Komaitis M. E.
Published: November 2010

A method is described for the qualitative determination of butylated hydroxyanisole, butylated hidroxytoluene, propyl gallate, octyl gallate and dodecyl gallate in edible fats and oils. The method is based on the development of a specific colour derived from the reaction of the antioxidants with N,N-dimethyl-p-phenylenediamine in the presence of a mild oxidizing agent in alkaline solution.
The method gave good results and can be carried out easily with facilities existing in most analytical laboratories.
Kinetic study of biomethanation of condensed water from the thermal concentration process of olive mill wastewater
Authors: Borja Padilla R. , Martín Martín A. , Durán Barrantes María M.
Published: November 2010

A kinetic study of biomethanation has been carried out by using condensed water from the thermal concentration process of olive mill wastewater, which contained an organic load (6 g/l COD) that prevented it from reusing or spillage.
Two fluidized-bed bioreactors were used, one of them containing suspend biomass for reference, and the other with biomass supported on Sepiolite for the immobilization of microorganisms effecting anaerobic digestion.
The Chen-Hashimoto model of methane production has been applied, obtaining the values of the kinetic parameters μmax and K for each case studied.
The results showed an increase in the kinetic constants for the reactor with Sepiolite in relation to the one used as reference, and the value for K kinetic constant was duplicated.
Measurement of the degree of unsaturation of oils and fats using infra-red spectroscopy and its relationship with iodine value
Authors: Muniategui S. , Paseiro P. , Simal J.
Published: November 2010

An spectroscopy method to fast determination of the degree of unsaturation of oils and fats is described by measurement of intensity of the olefinic band at 3007 cm-1 Using SNGLE program, the peak heigt and peak area and also 1st derivate and 2nd derivate at 3007 cm-1 are calculated and relationships between these parameters and iodine values are studied. The best relationships were obtained with the measurements of net absorbance (r=0,9992: error index=1,75%) and area (r=0,9992; error index= 1,77%).
Aerobic purification of the effluents produced in the olive mill wastewater biomethanation process
Authors: Borja Padilla R. , Durán Barrantes María M. , Luque González M.
Published: November 2010

A study of aerobic treatment in batch regime of the effluents produced in the olive mill wastewater biomethanation process was carried out.
An 83% of effluents organic substances was removal after the third day of fermentation.
The substrate removal rate follows a zero-order kinetic for high concentrations, and a first-order kinetic for low organic matter concentration, during the last days of fermentation.
The kinetic parameters (qmáx and K) were obtained from Michaelis- Menten model.
Evaluation of the displacement of the superfatting agent in soft soaps
Authors: Crespo González N. , Preda Rodríguez D.
Published: November 2010

The metathesis that occurs in soaps superfatted with fatty acids is studied, verified and evaluated. The analysis deals with soaps in solution (shaving creams), in which the problem is showed clearly due to the hydrolysis of the soap. The study is concern on the main fatty acids of the analyzed samples. Knowing the fatty acids distribution, the expected theoretical concentrations of the fatty acids were estimated and were compared with those found by Gas Chromatography.
The family Euphorbiaceae, source of vegetable oils for the technochemical industry
Authors: Pascual Villalobos M. J. , Correal Castellanos E.
Published: November 2010

The family Euphorbiaceae includes a huge number of species some of which provide important raw materials such as rubber, cassava, waxes and oils.
In this study, the general botanical and chemical characteristics of this family are described firstly together with the chemical composition of their seed oils and a comparison with those of other families. Secondly, other chemical constituents of economic interest are reviewed and compared with the species already used for food, industry and medicine purposes.
A further revision is included on some of its genus with potential interest and on current industrial oil crops such as Ridnus, Euphorbia, Aleurites, Sapium, Jatropha, etc.
Finally, from an economic point of view, future prospects of some of these oils as raw materials for the chemical industry are given.
Kinetic study of the biomethanization of olive mill wastewater previously subjected to aerobic treatment with Geotrichum candidum
Authors: Borja Padilla R. , Martín Martín A. , Durán Barrantes M. M.
Published: November 2010

The apparent kinetic constant was determined for the anaerobic digetion of olive mill wastewater (OMW) which comes from clasical press factory previously subjected to aerobic digestion with Geotrichum candidum in view of his high content in organic matter. The results obtained revealed it to markedly decrease (from 1 to 0,2 days-1) with increase in its COD (from 6 to 11 g/l) in the presence of both free and supported on Sepiolite (Pansil) biomass. This shows the existence of an inhibition process which is determined by using the Levenspiel kinetic model.
Anaerobic digestion allowed up to 80% of the COD present to be removed with an average yield coefficient of 315 ml CH4 STP/g COD.
Influence of the amount, quality and composition of dietary fat on the composition and distribution of fatty acids in rat adipose tissue
Authors: Salgado A. , Márquez-Ruiz G. , Dobarganes M. C.
Published: November 2010

In this paper the effect of the 3 most important variables (quantity, quality and composition) of dietary fat on the distribution and composition of fatty acids in rat adipose tissue, is studied.
From the results obtained after feeding 11 groups of rats, the following conclusions stand out:
1 . - Fatty acid composition of rat adipose tissue is very variable.
Nevertheless, when the percentage of fat in the diet is higher than 12%, the fatty acid composition of the adipose tissue is similar to that of the ingested fat.
2.- The level of alteration of the fat in the diet clearly modifies the fat composition In adipose tissue. This fact might be due to the lower digestibility.
3.- Fatty acid distribution in adipose tissue is independent of the distribution in the ingested fat.
Study of effectivenness of octadecyl C18 extraction columns in the evaluation of the bitter taste (K225) in virgin olive oil. Error and analytical scheme of method the evaluation
Authors: Gutiérrez Rosales F. , Perdiguero Camacho S.
Published: November 2010

The present study developed two objetives: 1) to study the possibility of repeatedly using disposable C18 columns 2) to determine an appropriate analytical scheme and the inherent systematic error in the method to evaluate bitter substances in virgin olive oil.
The results confirmed that we were able to recover the principles of olive oil without reducing the effectiveness of the C18 a columns with repeated uses at least ten times. The evaluation method errors of the bitter taste have been determined, in order to determine it precision. The confidence limits calculated for defined work schemes have given sufficient precision.
Modifications produced in food proteins following interactions with oxidizing lipids. III. Nutritional and toxicological consequences
Authors: Hidalgo F. J. , Zamora R. , Girón J.
Published: November 2010

The nutritional and toxicological consequences of oxidizing lipid-protein interactions are reviewed in this part. Influence on protein quality and on the availability and metabolic transit of several amino acids as measured in animal assays are used to discuss the real importance of these reactions.
Determination of the induction period of soybean oil - Correlation between the Rancimat and various analytical tests
Authors: Rauen-Miguel A. M. O. , Esteves W. , Barrera-Arellano D.
Published: November 2010

The objective of this research work was to follow the evolution of peroxide, anisidine, totox. iodine and acid values and refractive index during the oxidation of soybean oil using the Rancimat method. Various temperatures were used in this case (110°, 120°, 130° and 140°C) and the oxidation curves obtained through the Rancimat were compared with those obtained by the variation of the traditional values above mentioned, against the time. It was observed that the correlation coefficients were high for all methods (0,849<r<0,997) but the induction periods obtained with the Rancimat were generally higher than those obtained with the other analytical tests.
Quantitative determination of antimicrobial preservatives in cosmetics called "dermoprotectors"
Authors: Crespo González N. , Preda Rodríguez D.
Published: November 2010

A rapid, easy and reproducible method is described for the quantitative determination of the usual antimicrobial preservatives used in the cosmetic industry in the Spanish market with a dermoprotector claim.
The method is also useful for soap bars and for surfactant solutions, in this last case the method of extraction is the only change.
Gas Chromatography has been chosen as the analytical process for the set up of this method because it is a rapid and available technique, and it allows the simultaneous resolution of all the studied preservatives.
Physico-chemical properties and the microflora of Moroccan black table olives
Authors: Asehraou A. , Faid M. , Jana M.
Published: November 2010

Eleven samples of Moroccan black table olives were analyzed for their microflora and the physico-chemical factors. A survey of the most frequent microorganisms including standard plate count (SPC), counts of the indicator microorganisms (total and fecal coliforms and enterococci), staphylococci. Salmonella, sporeforming bacteria (Clostridium and Bacillus) and yeasts and molds was determined. The physico-chemical factors grouped pH, aw, NaCl concentration and the ADV (Acid degree value) of the fatty matter. Results reported hereby showed a low microbial load except for the yeasts and molds. The values found for the physico-chemical factors (low for the pH and the aw and high for the ADV and salt content) would suggest an inhibitory effect on the initial microflora charge of the black table olives.
Influence of Dacus Oleae infestation on flavor of oils, extracted from attacked olive fruits, by HPLC and HRGC analyses of volatile compounds
Authors: Angerosa F. , Giacinto L. Di , Solinas M.
Published: November 2010

The authors have examined the influence of the Dacus Oleae infestation on the aroma of the oils obtained from olives of Coratina and Nebbio varieties at different levels of attack.
The results obtained indicated a worsening of the qualitative level of the oils obtained from increasing percentages of infested olives; these were found to have a great decrease of phenolic substances and higher contents of both volatile alcohols and aldehydes with an unpleasant sensation.
Of particular interest was hexanal/total volatile alcohols ratio, in which having been well correlated with the extent of infestation, would permit one to establish in an objective manner, if and how much the olives from which an oil has been extracted have suffered a Dacus attack.
Influence of altitude on chemical composition of Andalusian virgin olive oil. Mathematical classification equations
Authors: Ferreiro L. , Aparicio R.
Published: November 2010

The changes of chemical composition due to climatic influence, in virgin olive oil, is a research subject which has been scarcely developed. This paper studies this relation with Andalusian oils by altitude as an indirect parameter related to climate of their olive grow zones. It was found that sterols and some triterpenic alcohols and hydrocarbons show changes in relation with altitude. The oils were classified into two groups of altitude, valley and mountains, by mean of discriminant and regression analysis procedures. The rules were verified with samples harvested in 1988 and 1989. It was found a significative predictive power (more than 90%) when the variety is Picual.
Techniques for the isolation and concentration of vegetable oils volátiles
Authors: Morales M. T. , Aparicio R , Gutiérrez F.
Published: November 2010

One of the methods for food flavor evaluation is the analysis of volatile components. First step in this kind of analysis Is the isolation and concentration of volatiles. A review is carried out about different techniques applied in foods and especially in vegetable oils. Very different methods have been used, an explication of each one with its different cases are presented. Likewise the applications carried out in vegetable oils during last years are discussed.
Estimating triacylglycerols from fatty acids by chemometrics. An application in Spanish virgin olive oil
Authors: García Pulido J. , Aparicio López B.
Published: November 2010

The level of acceptation of "1, 3-random 2-random" pattern of acyl groups distribution in virgin olive oil glycerides has been analysed in 36 samples, by comparing the values of triacylglycerols obtained by HPLC with those reported by the cited theory. Hotelling's T2, Principal Components and Canonical Correlation Analysis have been used to study both data sets. The normality of the data distributions, the intra-and intergroup correlations of the triacylglycerols were studied before these multivariate statistical algorithms were applied.
An alternative way of estimating triacylglycerols from only total fatty acids has also been studied. A Stepwise Multiple Regression procedure has been employed, and Multiple R coefficients fluctuate between 0,75 and 0,94 except for the variable SOS.
Absorption of thermoxidized fats. II. Influence of dietary alteration and fat level
Authors: Márquez-Ruiz G. , Pérez-Camino M. C. , Ruiz-Gutiérrez V. , Dobarganes M. C.
Published: November 2010

In this paper, the influence of dietary fat alteration and level upon digestibilities of total fat, unsaponifiable matter and non-altered fatty acids, is studied.
11 groups of Wistar rats were fed diets containing non-heated and thermoxidized olive oils. Analytical techniques previously studied were used for isolation and evaluation of non-absorbed lipids present in feces.
The results obtained led to the following conclusions: - Digestibility of fat decreases with dietary fat alteration but it is independent of the dietary fat level.
- The apparent absorption of non-altered fatty acids is affected by the dietary fat alteration.
- Dietary fat alteration significantly contributes to increase excreted levels of unsaponifiable from endogenous sources.
Characteristics of the fermentation process that occurs during the storage in brine of Hojiblanca cultivar, used to elaborate ripe olives
Authors: Fernández González J. , Garrido Fernández A. , García García P. , Brenes Balbuena M. , Durán Quintana M. C.
Published: November 2010

The paper studies the changes of the physico-chemical and microbiological characteristics of the fermentation in aerobic conditions that occur during the storage stage of Hojiblanca cultivar used to elaborate ripe olives. Assayed treatments include all the conditions used at industrial level (correction of initial pH to 4,0-4,2 units with acetic acid, sodium chloride concentration ranging between 3 and 6%, green to yellow-pink green fruits and bubling of air at a rate of 0,3 liter per hour and liter of the vessel capacity).
The process was characterized by a maintenance of the pH values, a slow sugar consumption, very low content of carbon dioxide and progressive increase of the salt concentration. Gram-negative rods and Bacillus grew at the beginning of the process; however, the most representative germs of these fermentation were the yeasts, whose population grew rapidly from brining (at higher rate as the salt content was slower). They remained throughout the storage, although after 180 days a decrease tendency was observed. The most representative species were: Pichía membranae faciens (51% of frequency), Pichía fementans (6%) and Hansenula polymorpha (6%). No gas-pocket or shrivelling was appreciated in any treatment.
Kinetic study of the anaerobic digestion of olive mill wastewater, from the oil extraction using olivex, previously biotreated with Geotrichum Candidum
Authors: Borja Padilla R. , Alba Mendoza J. , González Becerra A.
Published: November 2010

A kinetic study of the anaerobic digestion of olive mill wastewater (OMW) which was obtained with the technological helper "Olivex", was carried out. An identical wastewater, obtained without this enzyme was also used. Both OMW were pre-treated aerobically with Geotrichum Candidum to eliminate the greater part of the phenolic compounds responsible for inhibition. The anaerobic process was carried out in bioreactors with microorganisms immobilized on two micronized clay supports, Sepiolite and Bentonite.
Assuming that the overall anaerobic digestion process conforms to a first-order kinetic, specific rate constants, Ko, were obtained by using the Roediger's equation in each case. In contrast to what takes place with both OMW without pretreatment, kinetic constant was observed virtually constant when the substrate concentration was increased, in the range of COD (chemical oxygen demand) studied. The mean value of this kinetic parameter was a 40% larger for the OMW obtained with Olivex compared to the reference OMW, in the two digesters used. Sepiolite favoured the kinetic and increased the yield coefficient compared to Bentonite.
Study of some changes in the rheologic, optic and thermic magnitudes of a refined and thermooxidized olive oil
Authors: Cabrera Martín J.
Published: November 2010

When heating an oil in the presence of oxygen, several reactions were produced, which caused some changes in its physical properties.
The oil used in this study was heated at 180°C for different periods of time until a maximum of 72 hours.
The concentration of unaltered triglycerides was determined by silica column chromatography, and the molar fraction corresponding to each heating period was calculated.
The specific volume, the dynamic viscosity and the refractive index were measured, and the obtained values were adjusted to the corresponding equations that relate these magnitudes with temperature.
The specific enthalpy and the melting point were also measured.
Finally, the changes experienced by the measured parameters, defined in the above equations were discussed in relation to the changes produced in the oil.
Treatment for green table olive fermentation brines
Authors: Garrido Fernández A. , Brenes Balbuena M. , García García P.
Published: November 2010

The paper studies the characteristics of the several procedures that might be used to regenerate green table olive fermentation brines with the aim of reusing them in other stages of the elaboration process and specially for the final packaging of these fruits. The reuse may considerably reduce the waste water pollution of the canning industry as brines make up about 80% of the organic pollutant lead of its waste waters.
The two most interesting methods are: adsorption with activated carbon, followed by a cross filtration to separate the adsorbent; and ultrafiltration.
The former, should be GA activated carbon, which is the most efficient, in a proportion ranging between 5 and 10 g per litre. For the second, a polysulphone 1.000 daltons molecular weight cut membrane at 18 bars pressure should be used. A previous treatment of brines with bentonite (2 g/l), a range of temperatures between 30 and 45°C as well as low suspended solids and polyphenol contents, increases efficiency notably.
In principle, an approximate study of costs shows that regenerated brines are obtained, using either of the two procedures, at slightly lower prices than fresh brines prepared from their ingredients.
Studies on carotenoids and oxidative stability of winter squash seed and soybean oils
Authors: Helmy H. E.
Published: November 2010

Winter squash seed and soybean oils were extracted with commercial hexane. Carotenoids and other pigments m the oils were studied using spectrophotometric and thin layer chromatographic analysis. Three types of pigments were identified: carotenoids. mainly lutein and β-carotene, chlorophyll and some unidentified pigments. Carotenoids content were 70, 60, 0 ppm in crude, refined and bleached winter squash seed oil, and 80, 65, 0 ppm in crude, refined and bleached soybean oil respectively.
Stability was evaluated for crude, refined and bleached winter squash seed and soybean oils and an 1:1 admixture. Mixing winter squash seed oil with soybean oil increased the stability of soybean oil. Crude oil showed greater stability than refined and bleached oils.
Kinetic study of anaerobic digestion process of wastewaters from ripe olive processing
Authors: Borja Padilla R. , Garrido Fernández A. , Durán Barrantes M. M.
Published: November 2010

A kinetic study of the anaerobic digestion process of wastewaters from black olive preparation was carried out. The bioreactors used accommodated various suspended micronized clay supports of different chemical composition (Sepiolite and Bentonite).
Assuming that the overall anaerobic digestion process conforms to a first-order kinetics, experimental data pairs, namely the methane volume yielded (G) and the time (t) fitted the equation: G=Gm·[1-exp (-Ko·t)], the rate coefficient, Ko, was determined in each of the situations studied. The support used has a marked influence on the kinetic constant of the process; the Sepiolite support yields significantly the highest values. The average Ko values, obtained in the rank of COD between 0 and 1 g/L were: 1,83 days-1 (Sepiolite) and 1,23 days-1 (Bentonite).
For values of COD greater than 1g/L, the specific rate constant decreased when the volume of wastewater added or substrate concentration was increased.
The yield coefficients of methane, Yp/s, were 333 and 316 mL CH4/g COD for the Sepiolite and Bentonite reactor, respectively. Treatment yields of COD were above 95% in all the cases.
Study of molar volume and refraction in of triglyceride (triacetin, tributyrin or tricaprylin) -alcohol (ethanol, 1-butanol or 1-hexanol) mixtures
Authors: Rodríguez Rodríguez M. , Galán Vallejo M. , Muñoz Cueto María J.
Published: November 2010

Values of molar refraction for every studied mixtures show linear plots versus molar fractions of triglyceride. Values of molar volume show this behaviour, but only for tributyrin-butanol or tricaprylin-butanol miscellas. However, in tributyrin-ethanol mixtures, volume contractions have been found, whereas triacetin-butanol and tributyrin-hexanol show volume expansions. These facts are related to the mode of being structured of the alcohol and triglyceride molecules in mixtures.
A linear relationship between molar volume and temperature have been found, and also a linear dependence between the coefficient of thermal expansion at constant pressure and the molar fraction of triglyceride.
Properties of vegetable oils modified by hydrogenation, interesterification and fractionation
Authors: Grompone M. A.
Published: November 2010

The advent of techniques of chemical processing (hydrogenation and interesterification) and physical processing (fractionation) provides the manufacturer the capacity of modifying one or many physicochemical properties of an oil or fat.
In the present paper the influence of the chemical interesterification and thermal fractionation without solvent on the physical properties (melting point, solid fat index) of the products obtained by partial hydrogenation of soybean oil is studied. Properties of mixtures of partially hydrogenated soybean oil and totally hydrogenated coconut oil are also determined.
The examples studied show that knowing the changes produced by current modification methods is useful to design fatty products for specific purposes.
Kinetic study of anaerobic digestion process of olive mill wastewater in the mesophilic and thermophilic ranges of temperature
Authors: Borja Padilla R. , Martín Martín A. , Durán Barrantes M. M. , Maestro Durán R.
Published: November 2010

A kinetic study of anaerobic digestion of olive mill wastewater in the mesophilic (from 30ºC to 40°C) and thermophilic (from 50ºC to 60ºC) ranges of temperature has been carried out. Two reactors containing suspended biomass were used.
The Chen-Hashimoto substrate utilization kinetic model has been applied, obtaining the values of the maximum specific growth rate of microorganisms, μmax,. and the kinetic constant, K, for each case studied.
The obtained results showed an increase of 55% and 34% for μmax and K, respectively, of the thermophilic anaerobic digestion process in relation to the mesophilic process.
The substrate utilization maximum rate value was reached for the hydraulic retention times of 7,7 and 11,6 days, for the thermophilic and mesophilic processes, respectively.
The use of supercritical fluids en the edible oil industry
Authors: Esquível M. , Bernardo-Gil M. G.
Published: November 2010

Residual olive oil extraction experiments were made with carbon dioxide under pressures of 12 and 15 MPa and 308.15, 313.15 and 318.15 K of temperature.
We may conclude through the experiments, that under these pressures and temperature of 313.15 K there is no selected extraction of fatty acids, and higher recovery rates can be obtained in a short period of time.
Evaluation of two cooking methods and precooking treatments on characteristics of chicken breast and leg
Authors: Salama Nadia A.
Published: November 2010

Breast and leg of chicken were soaked in NaCl (4%) or STPP (3%) solutions before cooking in convention or microwave ovens. More protein, lower fat and lipid oxidation (TBA) were found in breast than in leg. Moisture percent and total lipids decreased due to cooking process. Chicken parts cooked in microwave had less moisture and TBA values, while protein, total lipids, shear force and cooking loss were more than that cooked conventionally. Microwave cooked roasts were less tender and lighter in colour, but aroma and flavour liked better by cooking in convention oven. Soaking in STPP before cooking retained more moisture protein and fat in chicken parts as compared with NaCl or untreated samples. Moreover, it decreased cooking loss, lipid oxidation, shear value and improved tenderness and flavour.