bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of temperature on whey protein isolated (WPI) films adsorbed at the water-oil interface
Authors: Rodríguez Niño Mª Rosario , Carrera Sánchez Cecilio , Rodríguez Patino Juan M.
Published: October 2008

Heat-induced interfacial aggregation of a whey protein isolate (WPI) with a high content of β-lactoglobulin, previously adsorbed at the oil-water interface, was studied by interfacial dynamic characteristics (interfacial tension and surface dilational properties) performed in a automatic drop tensiometer coupled with microscopic observation and image analysis of the drop after heat-treatment. The temperature, ranging between 20 and 80 ºC, and protein concentration in aqueous bulk phase, ranging between 1.10-1 and 1.10-5% wt/wt, were studied as variables. The pH, and ionic strength were maintained constant at 5 and 0.05 M, respectively. During the heat-treatment, WPI films behave typically as viscoelastic with non-zero phase angle, but with increasing elastic characteristics as the heat-treatment progresses. During isothermal treatment the surface dilational modulus, E, increases and the interfacial tension, σ, and phase angle, φ, decrease with time to a plateau value. The time dependence of E can be quantified by a first-order equation according to two kinetic mechanisms. The rate of thermal changes in WPI adsorbed films increases with protein concentration in solution. Heat-treatment produces irreversible changes in WPI adsorbed films because the interfacial characteristics do not return to original values after cooling back to the initial temperature. Significant changes in interfacial characteristics and drop image associated with interfacial WPI gelation were observed at protein concentration as low as 1.10-5% wt/wt, even for heat-treatment at 40 ºC.
Determination of the milk fat content of fat mixtures
Authors: Glaeser H.
Published: October 2008

Methods for the determination of the milk fat content of fat mixtures are usually based on a butyric acid determination. This fatty acid is specific for milk fat. A conversion factor is used to calculate the milk fat content from the butyric acid content of the mixture. When applying this procedure, the natural variation of the butyric acid content of milk fat is not taken into consideration. Recently published data show that a considerable error may thus be introduced, making the interpretation of analytical results difficult. It is therefore proposed to envisage a control procedure which takes this aspect into consideration.
Argentinean peanut sauce similar to mayonnaise: chemical, nutritional and sensorial aspects
Authors: Johnston M. Guadalupe , Navarro Verónica M. , Brutti Nilda I. , Nepote Valeria , Grosso Nelson R. , Guzmán Carlos A.
Published: October 2008

The purpose of this study was to prepare a dressing using blanched Argentinian peanuts, that looks like mayonnaise and that has a patterns of a healthy nourishment. The general composition of the product, as well as the fatty acid composition and stability to oxidation were determined and compared to standard commercial mayonnaise and sunflower oil. A consumer test was performed on the product. The results showed a better nutritional quality of the peanut mayonnaise, due to a lower fat and caloric contents and a higher mono-unsaturated proportion of fatty acids than the other dressings. This product contains fiber and vitamin E, it lacks cholesterol and is low in sodium. The stability to lipid oxidation was similar to that of standard commercial mayonnaise and sunflower oil. Concerning sensorial aspects, the product was well accepted by 71.7 % of the consumer panelists. It responds to healthy-food guidelines and can be used for various purposes.
Near-Infrared spectroscopy (NIRS) analysis of intact olive fruit: an useful tool in olive breeding programs
Authors: León L. , Rallo L. , Garrido A.
Published: October 2008

The objective of this study was to evaluate the potential use of Near-Infrared Spectroscopy (NIRS) for the analysis of oil content, moisture and fatty acids composition in intact olive fruit. A total of 287 samples, each from a single plant from an olive breeding program, were scanned by NIRS between 400 and 1700 nm. Partial least squares (PLS) regression was used to create calibration models (with 70 % of samples) relating laboratory reference values to spectral data (original, first and second derivative spectral data). The best equations obtained were validated (with 30% of samples) showing values of r2 of 0.88 % for the moisture, 0.83 % for oil content, 0.77 % for oleic acid content and 0.81 % for linoleic acid content. Therefore a reliable and accurate preselection can be made by using NIRS for both oil content and oleic acid content, with a nondestructive analysis, in a few seconds and without use neither production of chemical reagents.
Use of residual soapstock from the refining of edible vegetable oils to make biodiesel
Authors: Pereda Marín J. , Barriga Mateos F. , Álvarez Mateos P.
Published: October 2008

A procedure to obtain Biodiesel from “Oleinas” is studied. Biodiesel is a suitable product to replace diesel oil currently used to power the Diesel engines. It consists of a mixture of methyl esters of the fatty acids presents as triglycerides in vegetables oils (olive, sunflower, soya, rape oils). As a result of the refining of these oils for their use as food, a waste product is formed, the “oleinas” (acidulated soapstock). The oleinas consist of a mixture of triglycerides and free fatty acids, the latter amounting to 50% or more of the mixture and are subject to a fluctuating market, therefore it exist at times a problem for their disposal. In our research work we have tried to obtain biodiesel from oleinas. The process resulting from our experimental work is as follows: 1. Sterification of the free fatty acids with methanol, by acid catalysis, centrifuging the reaction product and removal of the acid-methanol phase. Drying of the latter. At this stage we have a product containing about 70% of methyl esters. 2. Transesterification of the triglycerides present in the sterified product with methanol by alkaline catalysis, washing the reaction product with a water methanol solution. Centrifuging and removal of the water-methanol phase. At this stage a biodiesel product is obtained containing about 90% of methyl esters. 3. Fractional vacuum distillation of the 90% biodiesel gives a final product with a methyl esters content higher than 98%.
Catolé palm (Syagrus oleracea Mart) fruits: fatty and amino acids composition
Authors: Bora Pushkar S. , Moreira Rosalynd V. R.
Published: October 2008

Catolé Palm (Syagrus oleracea Mart) Fruits were analysed for their chemical composition. The pulp and kernel portions contained 0.7 and 40.0% lipids. Freshly extracted kernel oil showed a small concentration (0.4 meq/kg) of peroxides but did not contain free fatty acids. The iodine and saponification values were 27.4 and 226, respectively. A large qualitative as well as quantitative difference in the fatty acid composition between the catolé pulp and kernel oil was observed. Fifteen and 19 fatty acids were identified in the pulp and kernel oil, respectively. These oils contained 48.9 and 73.2 % saturated fatty acids. The principal saturated fatty acids of the pulp oil was palmitic (C16) acid, while that of kernel oil was lauric (C12) acid. Oleic acid was the main monounsaturated fatty acid in both oils. In pulp oil, linoleic (C18:2) and linolenic (C18:3) were present at 23.5 and 11,3% concentrations, while kernel oil contained only linoleic acid (3.59%). In relation to amino acid composition of proteins, pulp proteins presented better amino acid profile than kernel proteins. In pulp proteins, the essential amino acids were present at concentrations higher than recommended by FAO except for methionine and lysine, while kernel proteins were deficient in all essential amino acids except phenylalanine, isoleucine and threonine.
Mathematical modelling of the process of the lye treatment of table green olives
Authors: Maldonado M. B. , Zuritz C. A.
Published: October 2008

A diffusion model for a composite-wall, hollow semi-infinite cylinder, consisting of a thin skin and a thicker flesh, with constant flesh and skin effective diffusion coefficients, DL and DS, respectively, was successfully adjusted to the experimental data obtained during the debittering of green olives variety Arauco or Criolla at 15 ºC, 20 ºC and 25ºC and lye concentrations of 1.50 %, 2.25 % and 3.00 % of NaOH. The DL values ranged between 7.18x10-11 and 1.18x10-09 m2/s, and increased with increasing temperature and lye concentration. The DS values were almost two order of magnitude less than the DL values, and also increased with increasing lye concentration and temperature. They ranged between 4.30x10-12 y 9.32 x10-12 m2/s. Activation energies of diffusion of sodium were respectively for the pulp, 85.48, 77.03 and 71.90 kJ/mol, and 30.24; 29.38 and 22.88 kJ/mol for the skin, for lye concentrations of 1.50 %, 2.25 % and 3.00 %.
Experimental characterization of two varieties of sunflower with potential for oil production extracted with hexane and isopropyl alcohol
Authors: Gallegos-Infante José-Alberto , Rico-Martínez Ramiro , Rocha Guzmán Nuria E. , González-Laredo Rubén F. , Morales Castro Juliana
Published: October 2008

The sunflower oil require of an extraction process that reduce the amount of impurities, and the use of a solvent that has not implications over the environment. An alternative is the use of the isopropyl alcohol. In this work was studied the extraction conditions of two experimental varieties of sunflower Madero-91 and Cianoc-2, the controls were hexane and Sunflower seed variety Victoria. It was found differences on the physical characteristics and in the dispersion of the physical measures from the three varieties used. The percent yield of crude oil extracted with isopropyl alcohol was not different of the obtained with hexane. The level of free fatty acids was higher in the oils extracted with isopropyl alcohol than the oils extracted with hexane, no differences was found in the amount of malonic aldehide.
Effect of type and level of dietary fibre supplements in rats
Authors: Rashad Mona M. , Moharib Sorial A.
Published: October 2008

Both experimental and clinical studies have indicated that a novel source of dietary fibres is potentially hypolipidemic. In the present study, turnip, sugar beet, cabbage and fenugreek green leaves were used as natural new sources of dietary fibres, to examine their effects on nutritional parameters and lipid metabolism in rats fed for 8 weeks comparing with a control diet (fibre-free control). Chemical analyses of the 4 plants revealed that there are differences between the ratios of soluble and insoluble non - starch polysaccharides (NSP) and their monomers constituents. Higher levels of uronic acid were present in soluble fibre (NSP) in all fibre sources than that of insoluble one. Generally, highly significant decrease in the weight gain and food intake of the rats fed the 4 experimental diets after 8 weeks feeding comparing with those fed control diet. Rats fed turnip diet exhibited a highly significant decrease in all the nutritional parameters through the feeding period. Rats fed a diet supplemented with sugar beet fibre, have a highly significant decrease in the value of weight gain, food intake and Dapp over the feeding period. Sugar beet, cabbage and fenugreek green fibre-containing diets had lowering effect on serum total lipid, total cholesterol, LDL-C (except sugar beet) and triglycerides levels than that of control diet fed rats. Supplemented the diet with turnip fibre had only lowering effect on serum triglycerides over the feeding period. Hepatic total lipid and total cholesterol levels were significantly lower when rats fed cabbage and fenugreek green fiber-containing diets. Highly significant decrease in the level of triglycerides was achieved in the liver of rats fed turnip fibre supplemented diet comparing with the experimental period (8 weeks).
Effect of sucrose polyesters on crystallization rate of vegetable ghee: solid fat content study
Authors: Ibrahim Nasir Mohammad
Published: October 2008

Crystallization rate of partial hydrogenated blend of soybean oil and cottonseed oil used for making vegetable ghee (vanaspati) was investigated, by solid fat content (SFC) using pulsed nuclear magnetic resonance (p-NMR). The effects of adding sucrose fatty acid esters or sucrose polyesters (SPE) on the crystallization rate of the blend fat were studied. Sucrose tetrastearate DK ester F-10 (stearate 70% - palmitate 30%) was added to the fat at different concentration, namely 0.5% and 1.0%. Blank sample and sample containing 0.5% and 1.0% DK ester F-10 / (DK F-10) were chosen to measure the change in SFC at constant temperature of 15ºC for a period of 25 hr. Five determinations of SFC were taken to the fat samples during the 25 hr i.e. 2,5,9,13 and 25th hr. SFC vs. time of crystallization of the three samples showed continuous increasing in SFC in all samples during the 25 hr, with sharp increasing at the first two hours. Samples containing 0.0% and 0.5% DK F-10, showed no significant difference in SFC during the first thirteen hours, while sample containing 1.0% DK F-10, showed higher SFC than the other two samples, through out the period. The amount of SFC for 1.0% DK F-10 sample at the 13th hour is equal to the SFC of the blank (0.0%) sample at the 25th hour. Melting point of the same samples increased with the increasing DK F-10 concentration in the fat samples. The results of SFC make it sure that the addition of 1.0% DK F- 10 will shorten the time required for the crystallization of vegetable ghee while the addition of 0.5% will not have significant effect.
Study of fatty acid contents in monovariety oils elaborated from olives produced in Extremadura (Spain)
Authors: Sánchez Casas Jacinto J. , Osorio Bueno Emilio , Montaño García Alfonso M. , Martínez Cano Manuel
Published: October 2008

Fatty acid composition of 483 samples of virgin olive oils from olives of the Extremadura varieties: Carrasqueña, Cacereña, Cornezuelo, Corniche, Morisca, Picual and Verdial de Badajoz, were analysed. After the quantitative analysis of main fatty acids, the variability according to the variety and state of ripening was studied. The discriminant analysis, taking the variety like grouping variable, explains more than 79,7 % of the variance with the two first functions and the model allows correctly classified 87,7 % of the 399 observations. The method, validated with the rest of analysed samples, improves the classification up to 89,3 %.
Olive oil intake in relation to cardiovascular diseases
Authors: Zampelas Antonis , Kafatos Anthony G.
Published: October 2008

Atherosclerosis is the principal contributor to the pathogenesis of coronary artery disease (CAD). Epidemiological, clinical and metabolic studies have reported protective associations between (extra virgin) olive oil consumption and CAD. As a key component of the Mediterranean diet, olive oil is a rich source of oleic acid, making up about 29 % of the daily dietary caloric intake, and antioxidants (vitamin E and phenolic compounds). Olive oil has beneficial effects by reducing LDL plasma concentration, the LDL cholesterol:HDL cholesterol ratio, and protecting LDL against oxidation. The progress of atherosclerosis and the risk of thrombo-embolic episodes could also be decreased through the reduction in plasma clotting factors levels, including FVIIc, PAI-1, XIIc and XIIa. The findings reaffirm low-moderate fat policies for optimum health, within which olive oil appears to be an important component of the diet.
Melting properties of some structured lipids native to high stearic acid soybean oil
Authors: List G. R. , Adlof R. O. , Carrierre C. J. , Dunn R. O.
Published: October 2008

A number of structured lipids native to high stearic acid soybean oil were synthesized and their physical properties were determined by pulsed nuclear magnetic resonance (NMR), Mettler dropping point and differential scanning calorimetry (DSC). 1,3 Distearo-2-olein (SOS), 1,3 distearo-2-linolein (SLS) and1,3 distearo-2-linolenin (SlnS) were synthesized from pure 1,3 diacylglycerols and the appropriate fatty acid. Pulsed NMR determinations over the temperature range 10-50 ºC showed that the symmetrical triacylglycerols (SUS: where S = stearic, U = oleic, linoleic or linolenic) are high and sharply melting materials, all showing substantial amounts of solids at temperatures up to 33.3 ºC, yet are completely melted at only a few degrees higher. Mettler dropping points for SOS, SLS and SlnS were 44.1, 37.9 and 36.5 ºC respectively. The heats of fusion for the structured triacylglycerols were determined by DSC and shown to be of the order 29-32 cal/gm compared to 45 cal/gm for SSS. The heats of fusion were also calculated from Mettler dropping point determinations as admixtures with soybean oil and showed consistent agreement with the DSC data.
Evaluation of diffusional effects on kinetics of soybean lecithin hydrolysis using A2 phospholipase
Authors: Maroto B. , Camusso C. , Zaritzky N.
Published: October 2008

Soluble or immobilized A2 phospholipase liberates one mole of fatty acid of the C-2 position in soybean lecithin phospholipids to product lysolecithins. When using the enzyme in its immobilized form the enzymatic activity decreases due to substrate and product transport phenomenon. By comparison of the kinetic parameters of the hydrolysis reaction catalized by A2 phospholipase immobilized on alumina or on DEAE-Sephadex against those of the soluble enzyme, for soybean lecithin hydrolysis reaction, the diffusive effects were evaluated. The decrease of the reaction rate was quantified in presence of diffusive effects and the effectiveness factors were calculated. The Michaelis-Menten kinetic parameters were determined: KM = 8,2.10-2 mol·l-1 and 5,36.10-2 mol·l-1 and Vmax = 7,7.10-5 mol·l-1 .min-1 and 9,5.10-5 mol·l-1 ·min-1 for the enzyme immobilized on alumina and on DEAE-Sephadex, respectively. The effectiveness factors were 0,277 for alumina and 0,376 for DEAE-Sephadex.
Formation of stigmasta-3,5-diene in olive oil during deodorization and/or physical refining using nitrogen as stripping gas
Authors: León-Camacho M. , Alvarez Serrano M. , Graciani Constante E.
Published: October 2008

Changes in the content of stigmasta-3,5-diene during industrial physical refining of bleached olive oil were studied in an experimental discontinuous pilot plant of 250 kg capacity using nitrogen as stripping gas. Dehydratation of ß-sitosterol yields stigmasta-3,5-diene and by means of its quantification it is possible to detect the refined oils in virgin olive oils. A 23 experiment was carried out in order to study the relationships among the independent variables involved in the physical refining process (nitrogen flow, temperature and oil load). The apparent kinetic constants (Kap) during the deodorisation process in the formation of stigmasta-3,5-diene were determined. The values of the rate constants and other apparent thermodynamic parameters were determined.
Two phases olive pomace storage in ponds
Authors: Ramos Hinojosa Álvaro E. , Ruiz Méndez Mª Victoria
Published: October 2008

During the harvesting period 1999-2000, real samples of two phases olive pomace were taken from storage ponds in two extraction facilities located in Southern region of Spain , every month until a maximum of five months. In addition, lots of two phases olive pomace and second-centrifuged two phases olive pomace were divided in closed recipients and, also, in opened recipients, and were stored in laboratory at 36 ºC for 0, 1, 2, 4 and 6 months. Samples were analysed for moisture and fat content, and solvent-extracted; the resulting oils were analysed for acidity, fatty acid composition, polar compounds and triglycerides. The results indicate that oil deterioration increases throughout the storage period, particularly those oils extracted from surface and from second-centrifuged two phases olive pomace. The surface/volume ratio in the ponds should be as low as possible. Special attention should be paid to the storage of two phases olive pomace, establishing a maximum of two months in all cases.
olor changes and 5-hydroxymethyl furfural formation in zile pekmezi during storage
Authors: Tosun Ilkay
Published: October 2008

Zile pekmezi (white hard pekmez) is a traditional Turkish food which is produced from grape juice. Color, flavour and 5-hydroxymethyl furfural (HMF) contents are the most important quality parameters in Zile pekmezi. Browning is the most common quality problem in pekmez. In this study, reaction orders, rate constants and activation energies were evaluated for HMF formation and color difference ( ? E) variation in Zile pekmezi stored at 55, 65 and 75 °C over 9 days. The results indicated that HMF formation and ?E variation during thermal processing of Zile pekmezi followed zero order reaction kinetics at 55, 65 and 75 °C . Calculated activation energy for HMF and ?E were 158.63 kJ mol-1 and 40.04 kJ mol-1, respectively.
Utilisation of rapeseed protein isolates for production of peptides with angiotensin I-converting enzyme (ACE)-inhibitory activity
Authors: Pedroche Justo , Yust María M. , Megías Cristina , Lqari Hassane , Alaiz Manuel , Girón-Calle Julio , Millán Francisco , Vioque Javier
Published: October 2008

ACE activity is related to increased arterial pressure and coronary diseases. A rapeseed protein isolate was hydrolyzed with the protease Alcalase in order to investigate the possible presence of ACE inhibitory peptides in the resulting hydrolysates. Hydrolysis for 30 min yielded a hydrolysate with the highest ACE inhibitory activity. Two fractions of this hydrolysate obtained by Biogel P2 gel filtration chromatography were used for further purification of ACE inhibitory peptides. Three fractions with ACE inhibitory activity were purified by reverse-phase HPLC of Biogel P2 f ractions. This demonstrates that rapeseed protein hydrolysates represent a good source of ACE inhibitory peptides .
Physicochemical characteristics and fatty acid composition of oil from tree tomato (Cyphomandra betacea Sendt) seeds var. red and yellow
Authors: Belén-Camacho Douglas R. , Sánchez Euris D. , García David , Moreno-Álvarez Mario José , Linares Oscar
Published: October 2008

Tree tomato ( Cyphomandra betacea Sendt) is a Solanaceae originating from Peru . In Venezuela , it is cultivated in the Andean region and Aragua state. The objective of this research was to determine some physicochemical characteristics of oil extracted from tree tomato seeds of red (R) and yellow (Y) varieties. The parameters evaluated were: free oleic acidity (%, R= 1.1; Y= 1.1), saponification number (mg KOH/g, R= 195.3; Y= 196.2), iodine index (cg I2/g, R= 143.3; Y= 142.0), peroxide value (meq O2/kg, R= 1.5; Y= 1.4), unsaponifiable matter (g/kg, R= 19.6; Y= 20.3), refraction index at 40 ºC (R= 1.4720; Y= 1.4710), relative density at 20 ºC (R= 0.9236; Y= 0.9240). The fatty acid composition showed (%): palmitic acid (R= 7.7; Y= 7.4), stearic acid (R= 3.5; Y= 3.1), oleic acid (R= 16.3; Y= 17.7), linoleic acid (R= 69.0; Y= 69.3), and linolenic acid (R= 3.5; Y= 2.5). Tree tomato oil is recommended as a possible nutraceutic agent and salad-oil.
The influence of natural tocopherols during thermal oxidation of refined and partially hydrogenated soybean oils
Authors: Steel C. J. , Dobarganes M. C. , Barrera-Arellano D.
Published: October 2008

Samples of refined and partially hydrogenated soybean oils, with iodine values between 60 and 130, tocopherol-stripped or not by aluminium oxide treatment, were submitted to thermal oxidation, at 180 °C (during) for 10 hours. Samples were collected at 0, 2, 5, 8 and 10 hours, for the determination of dimers and polymers (degradation compounds) and tocopherols. The relation of iodine value to the formation of dimers and polymers and the role of originally present tocopherols in the protection of fats and oils against thermal degradation was verified. The degradation curves for tocopherols showed that α and γ -tocopherols were destroyed faster than β and δ -tocopherols. In addition, the degradation rate of tocopherols was greater in the more saturated fats. The formation of dimers and polymers was greater in the oil than in the hydrogenated samples and in the samples treated with aluminium oxide with respect to the original, untreated samples.
The tuna oil as ω-3 fatty acids source for egg of laying hens
Authors: Castillo-Badillo C. , Vázquez-Valladolid J. L. , González-Alcorta M. , Morales-Barrera E. , Castillo-Domínguez R. M. , Carrillo-Domínguez S.
Published: October 2008

Fish oils are a source of polyunsaturated omega 3 fatty acids (AG ω3), mainly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which supply many benefits to human health. Tuna oil was used as a source of marine 3ω FA to enrich eggs by supplementing the diet of egg-laying hens with tuna oil. One hundred and twenty White Leghorn hens of 90 weeks old were allocated on three treatments with four replicates each, on a completely random design. Treatments consisted of adding 1 % and 2 % of tuna oil to the diets. The total lipids and ω3FA of the eggs were determined. The egg-laying hen dietary tuna oil supplement (1 and 2 %) enriched eggs with 300 % more EPA (0.40, 1.37, 1.54 mg/g lipids) and DHA (7.90, 24.67, 24.50 mg/g lipids) versus the control egg . The ω6:ω3 ratio decreased ( 11.4:1, 3.8:1, 3.0:1) as dietary tuna oil increased. There were no differences (p>0.05) among treatments in productive performance and egg quality, except egg weight which decreased with the tuna oil.
Hydrolysis and oxidation of covering oil in canned dried tomatoes as affected by pasteurization
Authors: Baiano Antonietta , Gomes Tommaso , Caponio Francesco
Published: October 2008

The effects of pasteurization on the chemical quality of the extra-virgin olive oil used as a covering for canned dried tomatoes were studied during storage through conventional (acidity, peroxide value, p-anisidine value, spectrophotometric indexes) and non conventional (polar compounds) analytical determinations. All the performed analyses show that extra-virgin olive oil from pasteurized samples underwent hydrolytic degradation slightly more than unheated ones but resulted slightly less oxidized than oil from untreated vessels.
Determination of lipoxygenase activity in hake liver
Authors: Margenat Lucía , Jachmanián Iván , Grompone María A.
Published: October 2008

Different studies were conducted to confirm the presence of active lipoxygenases in hake liver. These enzymes may be responsible for the rapid oxidation of oil contained in the liver. Incubation of a solution of free fatty acids obtained from sunflower oil with an aqueous extract obtained from hake liver resulted in a steady increase in the concentration bof hydroperoxides. A linear correlation was determined between extract concentration and the rate of oxidation of free fatty acids. The addition of antioxidants led to a sharp reduction in the rate of oxidation. The lipoxygenase activity in hake liver was found to be 100,000 times smaller than for soybeans –as determined under the same experimental conditions. Optimum activity was found in the pH range of 8.0 to 8.5.
Situation of European SMEs in the olive oil and table olive area. Survey.
Authors: De la Viesca Rosa , Fernández Elena , Fernández Silvia , Salvador Javier
Published: October 2008

A study of the situation of European Small and Medium Enterprises (SMEs) in the olive oil and table olive sector is carried out in order to find their main needs in the following aspects: information, participation in Research, Development and Innovation (R+D+I) programmes, Information and Communication Technologies (ICTs) implementation, quality control, environmental impacts, etc. The data used in this study were obtained through questionnaires sent to SMEs in France, Germany, Greece, Italy, Portugal, Spain and Turkey. The results obtained show: a reasonable acceptance of ICTs, a high interest in training courses on the most recent and pertinent legislation, and in product quality improvement and marketing.
Study of oils from the protected denomination of origin “Siurana” using excitation-emission fluorescence spectroscopy and three-way methods of analysis
Authors: Guimet Francesca , Ferré Joan , Boqué Ricard
Published: October 2008

The production area of the Protected Denomination of Origin (P.D.O.) “Siurana” olive oils can be divided into two regions: “Montsant” and “Camp de Tarragona”, with different orography, soil characteristics and climatic conditions. As a result of these differences, the oils have variable stability. Here we show that excitation-emission fluorescence can detect these variations. Oils from the “Montsant” region (more stable) show more fluorescence intensity above 500 nm (due to vitamin E) and less below 500 nm (due to oxidation products) than those from the “Camp de Tarragona” region. Discrimination between oils from the two P.D.O. “Siurana” regions was achieved by means of discriminant unfold partial least squares regression, giving a percentage of correct classification of 94 % for “Siurana-Camp” and 100 % for “Siurana-Montsant” oils.
Effectiveness of added natural antioxidants in sunflower oil
Authors: Carelli Amalia A. , Franco Indira C. , Crapiste Guillermo H.
Published: October 2008

The antioxidant activity of α- and δ-tocopherol, citric acid, ascorbic acid and ascorbyl palmitate was investigated in sunflower oil containing naturally occurring tocopherol. The effectiveness of natural antioxidants in sunflower oil was monitored by the accelerated oxidative stability test Rancimat and oxidation development during storage under different conditions. Samples in storage experiments were periodically removed and analyzed for peroxide value, p-anisidine value, total content and distribution of polar compounds, and residual naturally occurring tocopherol. The effectiveness of each antioxidant was strongly dependent on temperature and the testing method. While ascorbic acid appears to be the most effective antioxidant according to the Rancimat oxidative stability index, δ-tocopherol shows improved performance when considering storage experiments.
Evaluation of a simple and sensitive sensory method for measuring rancidity in soybean oils
Authors: López-Aguilar J. R. , Valerio-Alfaro G. , Monroy-Rivera J. A. , Medina-Juárez L. A. , O’Mahony M. , Angulo O.
Published: October 2008

The purpose of this study was to evaluate the efficacy of the 2 Alternative Forced Choice (2-AFC) sensory method in detecting rancidity in soybean oils. Additionally, correlations between the physico-chemical quality and the sensory attributes of edible soybean oils were studied. Soybean oil samples from four different plants were analyzed for their fatty acid profile, Free fatty acid (FFA), Anisidine Value (AV), Peroxide Value (PV), Conjugated Dienes (CD), Colour, Rancimat and TOTOX. The sensory attributes of the oils were measured using The American Oil Chemists Society (AOCS) sensory method and additionally, rancidity was assessed using the 2-AFC sensory method. All oil samples fit the quality control criteria for edible soybean oil. The 2-AFC The purpose of this study was to evaluate the efficacy of the 2 Alternative Forced Choice (2-AFC) sensory method in detecting rancidity in soybean oils. Additionally, correlations between the physico-chemical quality and the sensory attributes of edible soybean oils were studied. Soybean oil samples from four different plants were analyzed for their fatty acid profile, Free fatty acid (FFA), Anisidine Value (AV), Peroxide Value (PV), Conjugated Dienes (CD), Colour, Rancimat and TOTOX. The sensory attributes of the oils were measured using The American Oil Chemists Society (AOCS) sensory method and additionally, rancidity was assessed using the 2-AFC sensory method. All oil samples fit the quality control criteria for edible soybean oil. The 2-AFC  method was sensitive to small differences in rancidity. Differences in anisidine value and Rancimat were correlated to the difference in rancidity (d') among oils
Antioxidant activity of various plant extracts under ambient and accelerated storage of sunflower oil
Authors: Anwar Farooq , Jamil Amer , Iqbal Shahid , Sheikh Munir A.
Published: October 2008

The present study was conducted to investigate the antioxidant potential of 11 medicinally or economically important plant materials indigenous to Pakistan. The materials were extracted with 80% methanol and examined  for their antioxidant activity under different storage conditions using sunflower and soybean oils as oxidation substrates. Preliminary antioxidant activity assessment among the extracts was conducted with the TLC-test and by measuring percent inhibition of linoleic acid peroxidation. The rhizome of Iris germanica, leaves of Lawsonia alba, and M. oleifera, coffee (Coffee arabica) beans, rice (Oryza sativa) bran, wheat bran and oats (Avenis sativa) groats and hull, which showed higher antioxidant activity among the extracts, were further evaluated using soybean and sunflower oils as oxidation substrates. The vegetable oils were stabilized with extracts at a dosage of 0.12% (w/w), and individually subjected to accelerated (65 oC, 15 days) and ambient (6 months) storage. The oxidative deterioration level was monitored for the measurement of antioxidant activity index (AI), peroxide value (PV), conjugated dienes and trienes contents. Overall, the extracts of coffee beans, oat groats and hull, Iris germanica and M. oleifera leaves were found to be the most effective in extending oxidative stability, and retarding PV, primary and secondary oxidation products of soybean and sunflower oils. The order of efficiency of the plant extracts for stabilization of the subject oils was as follows: oat groats and hull > coffee beans > M. oleifera leaves > Lawsonia alba > Iris germanica > rice bran > wheat bran. Significant differences in the antioxidant potential of some of the extracts for stabilization of substrate oils were observed under ambient and accelerated storage conditions and thus demonstrated a variable antioxidant prospective of the extracts under different analytical protocols.
Docosahexaenoic acid (DHA), essentiality and requirements: why and how to provide supplementation
Authors: Valenzuela Alfonso , Julio Sanhueza B. , Nieto Susana
Published: October 2008

Lipids comprize from 50-60% of the structural matter of the brain and docosahexaenoic acid (C22:6, DHA) is the most  important omega-3 long-chain polyunsaturated fatty acid in the brain phospholipids comprizing 25% of the total fatty acids of the grey matter. The majority of the DHA present in the human brain is incorporated during the brain growth spurt which starts at week 26 of gestation and imposes a high demand for the fatty acid until about 2 years of age. DHA is required during brain development when neuronal and glial differentiation and migration, and active myelination and synaptogenesis take place. The fatty acid must be incorporated into the brain lipids as preformed DHA because less than 5% of its precursor (alpha linolenic acid, LNA) is converted to DHA. The human foetus has a limited ability to synthesize DHA from LNA, and therefore it must be largely supplied from maternal sources. Maternal DHA available for foetal nutrition can be provided from three main sources: adipose tissue, which is the main reservoir for the fatty acid; through biosynthesis from the precursor LNA, which occurs mainly in the liver; and as preformed DHA from dietary sources. In the postnatal period DHA is provided by the mother to the newborn through milk secretion. Western nutrition provides low LNA and DHA and Expert Nutrition Committees suggest that mothers should receive DHA supplementation during pregnancy and lactation. At present DHA supplementation can be provided from different sources: as purified free DHA, as an ethyl ester derivative, extracted from single-cell algae oils, from egg yolk phospholipids, or in the form of sn-2 DHA monoacylglycerol. In this review we revise and discuss the evidence of DHA requirements for the newborn, the need for maternal supplementation during pregnancy and nursing, and the alternatives at present for providing DHA supplementation.
Use of high power ultrasounds in virgin olive oil extraction process. Results at laboratory scale
Authors: Jiménez Márquez Antonio , Beltrán Maza Gabriel , Uceda Ojeda Marino , Aguilera Herrera María Paz
Published: October 2008

The effects of high-power ultrasound on olive paste, in a laboratory thermomixing operation for virgin olive oil extraction, have been studied. Indirect sonication in a thermomixer with an ultrasound cleaning bath, at 25 kHz, has been applied. A quick heating of olive paste, to optimal temperature conditions and an extractability improvement of the extraction process were found with the sonication of olive paste.The effects of high-power ultrasound on some components of the oil obtained were studied. Free acidity, peroxide value, K270, K232, and bitterness (K225) were determined immediately and 4 months later.
HPLC evaluation of the minor lipid components of by-products resulting from edible oil processing
Authors: EL-Mallah Mohamed Hassan , M.Hassanein Minar Mahmoud , EL-Shami Safinaz Mohamed M.
Published: October 2008

An analytical evaluation of some by-products resulting from edible oil refining processing steps has been carried out. By-product samples were taken from four different local refineries that apply chemical refining technology. Pretreatment of the representative samples of the by-products were done prior to analysis followed by chromatographic isolation and derivatization of the minor components, namely, free and acylated sterol (FS and AS) as well as free and acylated sterylglycosides (FSG and ASG). However, tocopherols were directly determined in the pretreated samples. HPLC, using different detectors, was carried out for the determination of these minor components. Several authors have focused on the analysis of sterols and sterol esters, as well as tocopherols in the refining byproducts; however sterylglycosides, as biologically important components, have not been dealt with. This study throws light on the by – products enriched with certain minor components to be possibly utilized as sources for such components. Also, the role of the conditions of the refining steps followed in removing these valuable minor components from oils was discussed. It was found that soapstock samples contained various amounts of total tocopherols ranging from 80 to 230ppm; total FS and AS ranged from 240 to 4000 mg/100g while total FSG and ASG ranged from 1120 to 6375 mg/100g. In the case of deodorization distillate samples total tocopherols ranged from 960 to 7360ppm; total FS and AS ranged from 1020 to 4160 mg/100g and total FSG, ASG ranged from 395 to 880 mg/100g.
Fatty acid profile of the fat from three pepper varieties (Arnoia, Fresno de la Vega and Los Valles-Benavente). Effect of the ripening stage
Authors: Martínez S. , Curros A. , Bermúdez J. , Carballo J. , Franco I.
Published: October 2008

Total fatty acids content was studied in three varieties of peppers (Arnoia, Fresno de la Vega and Los Valles-Benavente) in different commercial stages of ripening: green and red in the Arnoia variety and, green, breaker and red in the Fresno de la Vega and Los Valles-Benavente varieties. With ripening, an increase was observed in the lipid content in the peppers of all three varieties; the values showed are inside the range described in the literature for other varieties. At the end of maturation (red peppers), fat content allows for differentiating the three varieties under study. The fatty acid profiles were similar in the three varieties of peppers and in the three stages of ripening: the most abundant fatty acid was linoleic (C18:2) followed by linolenic  (C18:3) and palmitic (C16); these fatty acids represent more than 80% of the total fatty acids and do not show important variations during ripening in the three varieties of peppers. Minor changes in the major and minor fatty acids during ripening were observed in the Los Valles-Benavente variety. Using discriminant analysis 100% of the green, breaker and red peppers were correctly classified and differentiated from their content (%) in individual fatty acids: C16, C16:1, C17, C18, C18:1Z,T, C18:2 y C18:3.
The traditional Spanish paprika processing in the Murcia Region and possible innovations
Authors: Fernández-Trujillo J. Pablo , Escarabajal David
Published: October 2008

The traditional method of Spanish paprika processing in the Murcia Region is under the official category Denomination of Origin “Paprika of Murcia”. The process consists basically in manual harvesting the fruit in full ripe stage, drying, removing the peduncle and seeds, hammer and stone milling for crushing and grinding, transmission, mixing and granulating, sterilization, packaging and refrigerated storage. The details about the paprika processing operations are reported. In a second part the main control points of paprika processing, paprika quality traits and risks are also mentioned. The innovations proposed for paprika processing and unit operations in the literature include application of hygienic food processing design, paprika processing in a nitrogen flow, heat pretreatments before grinding or applied to shredded pepper, high hydrostatic pressure or high intensity electrical field pulse, irradiation, osmotic dehydration, lyophilization, mixing and coating, and modified atmosphere packaging. The traditional method of Spanish paprika processing in the Murcia Region is under the official category Denomination of Origin “Paprika of Murcia”. The process consists basically in manual harvesting the fruit in full ripe  stage, drying, removing the peduncle and seeds, hammer and stone milling for crushing and grinding, transmission, mixing and granulating, sterilization, packaging and refrigerated storage. The details about the paprika processing operations are reported. In a second part the main control points of paprika processing, paprika quality traits and risks are also mentioned. The innovations proposed for paprika processing and unit operations in the literature include application of hygienic food processing design, paprika processing in a nitrogen flow, heat pretreatments before grinding or applied to shredded pepper, high hydrostatic pressure or high intensity electrical field pulse, irradiation, osmotic dehydration, lyophilization, mixing and coating, and modified atmosphere packaging.
Vitamin E and vegetable oils
Authors: Sayago A. , Marín M. I. , Aparicio R. , Morales M. T.
Published: October 2008

An interest in vitamin E has increased in recent years due to its potent antioxidant properties and its role in preventing age-related diseases, cardiovascular diseases or Alzheimer. This work describes the biogenesis, bioavailability, nutritional requirements, activity and properties of vitamin E. Vegetable oils constitute one of the main sources of vitamin E dietary intake and an extensive bibliographic revision of this vitamin in vegetable oils is carried out from four points of view: antioxidant properties, health benefits, effects of external agents and effects of processing on vitamin E content and analytical techniques used for its analysis.
Study of ozonized theobroma fat using Proton Nuclear Magnetic Resonance and microbiological analysis.
Authors: Díaz Gómez Maritza F. , Martínez Téllez Goitybell , Gavín Sazatornil José A. , Meneau Hernández Rosa I. , Fernández Torres Irán
Published: October 2008

Ozonation of theobroma fat at different applied ozone dosages was carried out and peroxide indexes along with antimicrobial activity were determined. The reaction products were identified using Proton Nuclear Magnetic Resonance Spectroscopy (1H NMR). The principal signal intensity values were used for following the reaction course between ozone and theobroma fat. The reaction was followed up to peroxide index values of 544 mmol-equiv/kg. The intensities of olefinic proton signals decreased with the gradual increase in ozone concentration until disappearing completely. The Criegee ozonides obtained at 87.4 mg/g of ozone doses were approximately 3.7 times higher than at the beginning of the reaction. The highest action spectrum of antimicrobial activity was obtained with the higher peroxide index. These results suggest that the 1H NMR spectroscopic technique provides valuable information about of the ozonization grade of theobroma fat which produces an affective antimicrobial activity against Candida albicans
Seed protein characterisation of eleven species of amaranthus
Authors: Juan R. , Pastor J. , Alaiz M. , Megías C. , Vioque J.
Published: October 2008

The protein profile and the amino acid composition of eleven amaranth species have been studied. The following species were taken into account: A. viridis, A. powellii, A.muricatus, A. deflexus, A. graecizans, A. blitoides, A. retroflexus, A. blitum, A. albus, A. cruentus and A. hypochondriacus. Seed samples were obtained from wild populations located in the southwest of Spain. The protein profile was studied by gel filtration chromatography and denaturing electrophoresis. Profiles were similar in all taxa, with small variations in the molecular weights and amounts of the main seed proteins. Thus, after gel filtration chromatography six main fractions of around 300 kDa, 180 kDa, 120 kDa, between 40 and 50 kDa, 20 and 30 kDa and below 10 kDa were observed. On the other hand, the electrophoretic analysis showed peptides grouped into three main fractions, between 50 and 64 kDa, 33 and 37 kDa and 18 and 25 kda. The most balanced amino acid compositions were observed in the wild taxa A. muricatus, A. blitum and A. powellii showed the most equilibrated amino acid composition. A. hypochondriacus and A. graecizans showed the most deficient amino acid composition with limitations in five essential amino acids. These results show the potential of wild amaranthus taxa for their introduction as crops or their use in the improvement by hybridization mechanisms of other crops such as A. hypochondriacus.
Differential scanning calorimetry. Influence of virgin olive oil composition on its thermal profile
Authors: Jiménez Márquez A , Beltrán Maza G , Aguilera Herrera M P , Uceda Ojeda M
Published: October 2008

Samples of olive oil from the cultivars ‘Arbequina’ and ‘Picual’, with different contents in polyphenols, were analyzed by means of differential scanning calorimetry. Three speeds of cooling/heating (1, 5 and 10ºC/min) were analyzed with the differences between duplicates being lowest when the analysis was carried out at 5°C/min. An important varietal effect (p
Plasmid DNA studies in Lactobacillus plantarum strains isolated from olive fermentations: production of and immunity to plantaricin OL15 is associated to a 9.6 Kb plasmid (pOL15)
Authors: Mourad Kacem
Published: October 2008

Previously 12 Lactobacillus plantarum strains were isolated from fermented olives. Among these, only L. plantarum OL15 produced bacteriocin (plantaricin OL15). In this study, the 12 strains were examined for plasmid DNA content. Of these, 9 strains have shown one to three plasmid bands ranging in size from 5.4 to 12.2 kb. L. plantarum OL15 exhibited one plasmid (9.6 kb) which was named pOL15. After curing with novobiocin and ethidium bromide, the plasmid profile analysis of non producing derivatives, showed that the 9.6 kb plasmid pOL15 harbored by the parental strain had been lost in all cases and none of them regained the ability to produce plantaricin OL15 suggesting that the production of plantaricin OL15 is plasmid linked. Plantaricin OL15 was not inactived by amylase and lipase suggesting that plantaricin OL15 activity was not dependent on the presence of either a carbohydrate or lipid moiety. Plantaricin OL15 showed activity against lactic acid bacteria of different species and also against olive spoilage and phytopathogenic bacteria, including Pseudomonas and Erwinia.