This chapter presents physical and chemical properties of oils extracted from weed and ornamental... more This chapter presents physical and chemical properties of oils extracted from weed and ornamental species seeds that grow in Argentina. Their localization and common name will be provided. Information on possible renewable oil products with a potential industrial use is presented. Their fatty acid composition and minor components will be analized.Fil: Perez, Ethel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Departamento de Ingeniería Química; Argentin
Fil: Burnet, Margarita Andrea. Universidad Nacional del Centro de la Provincia de Buenos Aires. F... more Fil: Burnet, Margarita Andrea. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingenieria Olavarria; Argentina
European Journal of Lipid Science and Technology, 2020
The main goal of this work is to evaluate the extraction of sunflower oil from enzyme‐treated col... more The main goal of this work is to evaluate the extraction of sunflower oil from enzyme‐treated collets using ethanol and isopropanol (IPA) as solvents. The sunflower collets are pretreated with the multienzyme complex Viscozyme L prior to solvent extraction by the Soxhlet method. The influence of the moisture content of the collets, pretreatment, processing time, and solvent type on the amount of total extracted material and the oil extraction efficiency is studied. Some quality parameters such as phospholipid content of the oil and chlorogenic acid content of the residual meal are also analyzed. At low moisture content (7%) the solvents exhibit similar oil extraction ability (98–99%), but with increasing moisture the extraction efficiency of ethanol decreases to about 85%, while no significant differences are observed for IPA. The enzymatic treatment increases the extraction efficiency for all times, especially for ethanol. It is observed that IPA is more efficient in the extraction...
The desolventization kinetics of oilseed meals with superheated solvent was investigated experime... more The desolventization kinetics of oilseed meals with superheated solvent was investigated experimentally and theoretically. A bench-scale equipment was designed and built to measure continuously the rate of mass loss and the solid temperature during desolventization of meal particles. Experiments were carried out with sunflower and soy meals using superheated hexane vapor as desolventizing fluid and temperatures ranging from 90 C to 135 C. Experimental data were used to determine the vapor-particle heat transfer coefficient under different conditions, which compare reasonably with predictions of dimensionless correlations for solid particles. A relatively simple mathematical model to represent the desolventization kinetics of individual meal particles, based on heat transfer in a receding front system, was developed. The model was used to analyze the effect of temperature, particle diameter, shrinkage and mass transfer on desolventizing rate. Prediction of desolventization kinetics of sunflower and soy meals compared satisfactorily against experimental results at different temperatures. This work expands the knowledge of technical information on the desolventization of sunflower and soybean meal particles with superheated hexane and provides a suitable model to represent the desolventizing kinetics under different conditions. This information can be applied to simulate, design and optimize the desolventizing process of oilseed meals with superheated solvent in fixed and fluidized beds.
In this study the kinetics of oil extraction from partially dehulled safflower seeds under two mo... more In this study the kinetics of oil extraction from partially dehulled safflower seeds under two moisture conditions (7 and 9% dry basis) was investigated. The extraction assays were performed using a stirred batch system, thermostated at 50 °C, using n-hexane as solvent. The data obtained were fitted to a modified diffusion model in order to represent the extraction kinetics. The model took into account a washing and a diffusive step. Fitting parameters were compared statistically for both moisture conditions. The oil yield increased with the extraction time in both cases, although the oil was released at different rates. A comparison of the parameters showed that both the portion extracted in the washing phase and the effective diffusion coefficient were moisture-dependent. The effective diffusivities were 2.81 10 -12 and 8.06 10 -13 m 2 s -1 for moisture contents of 7% and 9%, respectively.
The Canadian Journal of Chemical Engineering, 2015
In this work the kinetics of oil extraction from spring canola seeds subjected to a hydrothermal ... more In this work the kinetics of oil extraction from spring canola seeds subjected to a hydrothermal pretreatment with direct steam (393 K, 5 min) was studied. The differences between the seed internal structure generated by the application of this pretreatment and that of the untreated sample (ground sample) were observed by scanning electron microscopy. Oil from both samples was extracted with hexane at different times and temperatures using a stirred batch system. Oil yield increased up to 46 % due to the hydrothermal treatment. A model was proposed to explain the oil extraction process from hydrothermally pretreated and untreated canola seeds, taking into account two main mechanisms: a washing process of the surface oil from the seed, and a diffusion process. Parameters of the model were fitted, and values of the oil fraction extracted during the washing step (0.27 and 0.50 for untreated and hydrothermally treated canola seeds, respectively) and the effective diffusion coefficient (...
ABSTRACT Dietary fibre enrichment of white bread with inulin-rich carbohydrate (IRC) powder extra... more ABSTRACT Dietary fibre enrichment of white bread with inulin-rich carbohydrate (IRC) powder extracted from Jerusalem artichoke tubers (IRC-J) was studied. Previously, it was shown that this IRC-J powder had higher prebiotic activity score than a commercial chicory inulin (IRC-C) powder, used for comparison. For bread making, 2.5 and 5.0 g of either IRC-J or IRC-C were added to 100 g of wheat flour, and the effects on dough viscoelastic properties and bread quality properties were analyzed, relative to a control sample (no IRC added). The lowest IRC concentration of both fibres had no significant effect on the elastic modulus (G’) of the dough, but the highest IRC level decreased G’, with a stronger effect of IRC-J. This was attributed to disruption of the starch-gluten matrix due to fibre replacement of flour. In turn, this was thought to impair gas retention (known as diluting effect), resulting in the observed decrease of bread specific volume and Cell/Total Area ratio, and the increase in crumb hardness and chewiness. IRC addition also had a significant effect on crumb and crust colour, and other crumb grain features. These effects were more significant at the highest IRC concentration of both fibres. Breads with 5.0 g of IRC-J were significantly darker, flatter, and more humid. All the sensory attributes of breads with 0 (control sample), 2.5 g IRC-J, and 2.5 g IRC-C were acceptable, and no significant differences were found between the three samples, in any of the attributes.
Frutos de Ligustrum lucidum Ait y Ligustrum sinense Lour fueron cosechados en Olavarría (provinci... more Frutos de Ligustrum lucidum Ait y Ligustrum sinense Lour fueron cosechados en Olavarría (provincia de Buenos Aires, Argentina) y sus semillas separadas en forma manual. Las semillas se agotaron con n-hexano, obteniendo los aceites crudos con rendimientos del 8,7-10% y 10,7 % (base seca), respectivamente. Los aceites crudos se examinaron en sus características fisicoquímicas (Índice de refracción: 1,4647 y 1,4640 (a 25 o C), Indice de iodo: 93,7 y 88,8, Indice de saponificación: 167 y 154, insaponificable: 11 y 18 %, Indice de acidez: 4,8 y 9,2 (mgKOH/g) respectivamente. El análisis por cromatografía gaseosa de los ésteres metílicos reveló alto porcentaje de ácido oleico (57,8 y 51,1%), alrededor de un 25,1 y 29,6 % de ácidos saturados, respectivamente, predominando el ácido palmítico, pero con un significativo contenido de ácidos de más de 18 átomos de carbono. Las harinas residuales de extracción contenían baja proporción de proteína cruda y de lisina disponible. Se informan valores de fósforo total y de ácido fítico, cenizas, calcio, fibra cruda, hidratos de carbono.
ABSTRACT In this work a statistical method of comparison was used in order to compare the paramet... more ABSTRACT In this work a statistical method of comparison was used in order to compare the parameters of a modified diffusion model representing the kinetics of canola oil and tocopherol extraction. The model takes into account an initial stage where solvent removes the oil from the surface of the ground seed by washing. Kinetic tests were carried out in a batch extractor at different temperatures (from 25 to 60 °C) using hexane as solvent. Tocopherol concentration in the extracted oil was determined by HPLC.The parameter comparison showed that the portion extracted during the washing stage was only temperature-dependent in the case of tocopherol extraction, whereas the effective diffusion coefficients were temperature-dependent in oil and tocopherol extraction. The diffusivities ranged from 1.3 × 10−12 to 3.0 × 10−12 m2 s−1 and from 1.6 × 10−12 to 2.3 × 10−12 m2 s−1 for oil and tocopherol extraction, respectively. The oil and tocopherol extraction activation energy was 19.1 kJ mol−1 and 8.1 kJ mol−1, respectively.
Pectinase-assisted solvent extraction of oil and total tocopherol from sunflower hybrids with dif... more Pectinase-assisted solvent extraction of oil and total tocopherol from sunflower hybrids with different structural characteristics was studied by means of laboratory tests carried out in a stirred batch extractor at 50 °C. From the oil yield results obtained for the two hybrids studied, black-hull (P20) and striped-hull hybrids (ACA 884), it could be observed that oil was extracted at different rates in both hybrids. Analyzing the performance data versus time in the control samples, ACA 884 oil was released more easily and remained invariant with time, whereas for P20 the extraction was slower and the maximum value was reached at 60 min. The fiber wall structure collapsed by the enzymatic action, improving oil release and allowing a faster extraction. The efficiency of the treatment was measured in terms of the percentage of increase in oil yield compared with the control samples. It was observed that in hybrid ACA 884 the mean increases were not significantly different (p = 0.9295) over time (4.12% d.b.). Hybrid P20 showed a significant increase in the percentage of oil yield (p = 0.0001) at 10 min (10.85% d.b.), and then it remained virtually constant over time (4.89% d.b.). The black-hull hybrid (P20) presented significant differences in fatty acid composition due to the enzymatic action. Pectinase treatment was highly effective in the tocopherol extraction from hybrid P20 (p < 0.001), obtaining a 32.3% increase on average. The maximum values were 662 and 220 lg g dried ground seed À1 at 60 and 120 min for black-hull and stripedhull hybrids, respectively. The enzymatic treatment effectively produced an increase in oil and tocopherol yields for the black-hull hybrid.
In the present work the in vitro prebiotic activity of inulin-rich carbohydrates using Lactobacil... more In the present work the in vitro prebiotic activity of inulin-rich carbohydrates using Lactobacillus paracasei as probiotic microorganism was determined. With this purpose, inulin-rich carbohydrates samples from Jerusalem artichoke tubers stored at 4-5 °C during different times along an overall period of 8 months were extracted. Extraction yield, inulin content and average polymerization degree of inulin-rich carbohydrates samples were also determined. For all samples, extraction yield and inulin content decreased with storage time. In particular, inulin content exhibited values within the range of commercial food grade inulin (≥85%). Average polymerization degree values decreased with storage time ranging from 12.1 to 8.3. The in vitro prebiotic activity of inulinrich carbohydrates samples was assessed using a prebiotic activity score which considered the growing ratio relative to glucose of L. paracasei as well as of the enteric bacteria Escherichia coli when such carbohydrates were used as C source. Inulin-rich carbohydrates extracted from tubers cold-stored during 4 months showed the highest prebiotic activity score, even higher than the corresponding to a commercial food grade inulin, indicating that this sample should be used as a prebiotic food ingredient, representing a potential alternative to the available commercial inulin obtained from chicory roots.
The Canadian Journal of Chemical Engineering, 2014
The aim of the present work was to determine the optimum operating conditions in hydrothermal pre... more The aim of the present work was to determine the optimum operating conditions in hydrothermal pretreatments applied to canola seeds. The effect of these pretreatments on the canola oil extraction yield and quality was evaluated. Samples were characterized by proximate analysis. Acidity and peroxide value were studied as parameters for the determination of oil quality. Seeds were exposed to direct steam contact in an autoclave. Pretreatments were carried out using different temperatures (100, 120 and 130 8C), exposition times (5, 15 and 30 min) and seed granulometry (ground seeds, with a particle size in a range from 0.420 to 1.000 mm; broken seeds, with a particle size ranging from 1.000 to 1.410 mm, and entire seeds). After each hydrothermal pretreatment, oil extraction was carried out by the Soxhlet method (hexane). The Taguchi method was followed in order to explore the optimum operating conditions by using an L9 experimental design, and select the most favourable levels of each variable. Initial oil content was 44.2% dry basis (db). The selected optimum experiment, using a temperature of 120 8C, a time of 5 min and broken seeds, generated an oil yield increase of 20% compared with non-hydrothermally treated seeds, whereas quality parameters remained within the accepted values for trade standards.
As part of a study to characterise and examine the use of wild sunflower species (Helianthus peti... more As part of a study to characterise and examine the use of wild sunflower species (Helianthus petiolaris Nutt), some physical properties and morphological characteristics of seeds from different locations in Argentina were determined. The oil content ranged between 27% and 30% (wb) and the moisture content varied from 8Á9% to 10Á4%. The average length, width, and thickness of the seed, measured with a micrometer, were 4Á5, 2Á02, and 1Á2 mm, respectively. The calculated mean values of seed equivalent diameter, surface area, and sphericity were 2Á25 mm, 16Á2 mm 2 , and 0Á48, respectively. The bulk and true densities measured with a hectolitre tester and by picnometry, respectively, were 350 and 399 kg/m 3 . The angle of repose ranged between 28Á61 and 30Á21. The morphological characteristics as well as the hull thickness and percentage were also evaluated by scanning electron microscopy. The hull thickness and percentage had mean values 0Á07 mm and 21%, respectively. Achenes presented straight and double hairs and a morphological study showed a pericarp structure with an amorphous and lignified fibre layer and air cavities between the inner parenchyma and the cotyledon.
The aim of this work was to study the patterns of the accumulation of carbohydrates, organic acid... more The aim of this work was to study the patterns of the accumulation of carbohydrates, organic acids, and minerals at different development stages of Hexachlamys edulis fruit for its evaluation as a source of health-promoting compounds, which is necessary in order to be included in the Argentine Food Code. Additionally, the obtained results will allow for deciding the optimal time for consumption to receive a better flavour and a good contribution of the nutrients evaluated. The succinic acid concentration (the major organic acid) was high in unripe fruit (112.33 mg/g of the dry weight), then decreased to a minimum in medium ripe and ripe fruit (92.48 to 99.43 mg/g of the dry weight,), to increase again in overripe fruit (115.65 mg/g of the dry weight,). Sucrose increased significantly from 21.20 mg/g of the dry weight in unripe fruit to a maximum of 82.53 mg/g of the dry weight in ripe fruit. Glucose increased significantly from 95.59 mg/g of the dry weight in unripe fruit to a maxim...
European Journal of Lipid Science and Technology, 2018
The aim of this work is to analyze the effect of moisture content of sunflower expanded material ... more The aim of this work is to analyze the effect of moisture content of sunflower expanded material on the quality of the extracted oil by determining its wax, phospholipids, and tocopherol content and composition. Sunflower oil extraction is carried out in a batch extractor at 50 °C using hexane and three moisture levels (5.65, 12.40, and 18.92% dry basis). The increasing moisture content causes an increment in both oil yield and total amount of minor compounds. The total wax content ranges between 808 and 1118 ppm, the wax fraction is composed mainly of esters of between 44 and 58 carbon atoms (>67%), and the distribution does not change with the moisture content. In all the experiments, α‐ and β‐tocopherols and β‐tocotrienol are detected, with the level of α‐tocopherol being higher than 93% and easier to extract at 12.40% moisture. Furthermore, the phospholipids content in the oil increases with moisture content but maintains its profile composition. The obtained results can be e...
Journal of the American Oil Chemists' Society, 2004
Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolari... more Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolaris Nutt and their comparison with those from cultivated sunflower (H. annuus) were performed. Seeds from indigenous populations of H. petiolaris were harvested in Argentina in different years. The analytical parameters studied were as follows: (i) FA profile, PV, p-anisidine value, oxidative stability, phosphorus and phospholipid content, tocopherols, polar compounds, and waxes in the extracted oils; and (ii) moisture, ash, crude fiber, metals, sugars, urease activity, starch, protein, available lysine, neutral detergent fiber, acid detergent fiber, lignin, gross energy, and amino acid content in the residual meals. The products from wild sunflower seed, which yielded 27-30% oil by solvent extraction, showed some characteristics similar to the commercial products. Nevertheless, the oil had lower quality and stability owing to the high unsaturation levels and lower concentrations of antioxidant components, and the meal had a lower protein content. The phospholipid content was significantly lower than in industrial crude sunflower oils. Most of the important parameters in the meal such as available lysine, gross energy, and digestibility compared favorably with those for cultivated sunflower meals. The results showed the potential for using these meals for animal feed.
Journal of The American Oil Chemists Society, 2004
Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolari... more Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolaris Nutt and their comparison with those from cultivated sunflower (H. annuus) were performed. Seeds from indigenous populations of H. petiolaris were harvested in Argentina in different years. The analytical parameters studied were as follows: (i) FA profile, PV, p-anisidine value, oxidative stability, phosphorus and phospholipid content, tocopherols, polar compounds, and waxes in the extracted oils; and (ii) moisture, ash, crude fiber, metals, sugars, urease activity, starch, protein, available lysine, neutral detergent fiber, acid detergent fiber, lignin, gross energy, and amino acid content in the residual meals. The products from wild sunflower seed, which yielded 27–30% oil by solvent extraction, showed some characteristics similar to the commercial products. Nevertheless, the oil had lower quality and stability owing to the high unsaturation levels and lower concentrations of antioxidant components, and the meal had a lower protein content. The phospholipid content was significantly lower than in industrial crude sunflower oils. Most of the important parameters in the meal such as available lysine, gross energy, and digestibility compared favorably with those for cultivated sunflower meals. The results showed the potential for using these meals for animal feed.
The temperature-dependent diffusion coefficients of interstitial hydrogen, deuterium, and tritium... more The temperature-dependent diffusion coefficients of interstitial hydrogen, deuterium, and tritium in nickel are computed using transition state theory. The coefficient of thermal expansion, the enthalpy and entropy of activation, and the pre-exponential factor of the diffusion coefficient are obtained from ab initio total energy and phonon calculations including the vibrations of all atoms. Numerical results reveal that diffusion between octahedral interstitial sites occurs along an indirect path via the metastable tetrahedral site and that both the migration enthalpy and entropy are strongly temperature dependent. However, the migration enthalpy and entropy are coupled so that the diffusion coefficient is well described by a constant activation energy, i.e., D = D 0 exp͓−Q / ͑RT͔͒, with Q = 45.72, 44.09, and 43.04 kJ/ mol and D 0 = 3.84ϫ 10 −6 , 2.40ϫ 10 −6 , 1.77 ϫ 10 −6 m 2 s −1 for H, D, and T, respectively. The diffusion of deuterium and tritium is computed to be slower than that of hydrogen only at temperatures above 400 K. At lower temperatures, the order is reversed in excellent agreement with experiment. The present approach is applicable to atoms of any mass as it includes the full coupling between the vibrational modes of the diffusing atom with the host lattice.
This chapter presents physical and chemical properties of oils extracted from weed and ornamental... more This chapter presents physical and chemical properties of oils extracted from weed and ornamental species seeds that grow in Argentina. Their localization and common name will be provided. Information on possible renewable oil products with a potential industrial use is presented. Their fatty acid composition and minor components will be analized.Fil: Perez, Ethel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; ArgentinaFil: Nolasco, Susana Maria. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingeniería Olavarría. Departamento de Ingeniería Química; Argentin
Fil: Burnet, Margarita Andrea. Universidad Nacional del Centro de la Provincia de Buenos Aires. F... more Fil: Burnet, Margarita Andrea. Universidad Nacional del Centro de la Provincia de Buenos Aires. Facultad de Ingenieria Olavarria; Argentina
European Journal of Lipid Science and Technology, 2020
The main goal of this work is to evaluate the extraction of sunflower oil from enzyme‐treated col... more The main goal of this work is to evaluate the extraction of sunflower oil from enzyme‐treated collets using ethanol and isopropanol (IPA) as solvents. The sunflower collets are pretreated with the multienzyme complex Viscozyme L prior to solvent extraction by the Soxhlet method. The influence of the moisture content of the collets, pretreatment, processing time, and solvent type on the amount of total extracted material and the oil extraction efficiency is studied. Some quality parameters such as phospholipid content of the oil and chlorogenic acid content of the residual meal are also analyzed. At low moisture content (7%) the solvents exhibit similar oil extraction ability (98–99%), but with increasing moisture the extraction efficiency of ethanol decreases to about 85%, while no significant differences are observed for IPA. The enzymatic treatment increases the extraction efficiency for all times, especially for ethanol. It is observed that IPA is more efficient in the extraction...
The desolventization kinetics of oilseed meals with superheated solvent was investigated experime... more The desolventization kinetics of oilseed meals with superheated solvent was investigated experimentally and theoretically. A bench-scale equipment was designed and built to measure continuously the rate of mass loss and the solid temperature during desolventization of meal particles. Experiments were carried out with sunflower and soy meals using superheated hexane vapor as desolventizing fluid and temperatures ranging from 90 C to 135 C. Experimental data were used to determine the vapor-particle heat transfer coefficient under different conditions, which compare reasonably with predictions of dimensionless correlations for solid particles. A relatively simple mathematical model to represent the desolventization kinetics of individual meal particles, based on heat transfer in a receding front system, was developed. The model was used to analyze the effect of temperature, particle diameter, shrinkage and mass transfer on desolventizing rate. Prediction of desolventization kinetics of sunflower and soy meals compared satisfactorily against experimental results at different temperatures. This work expands the knowledge of technical information on the desolventization of sunflower and soybean meal particles with superheated hexane and provides a suitable model to represent the desolventizing kinetics under different conditions. This information can be applied to simulate, design and optimize the desolventizing process of oilseed meals with superheated solvent in fixed and fluidized beds.
In this study the kinetics of oil extraction from partially dehulled safflower seeds under two mo... more In this study the kinetics of oil extraction from partially dehulled safflower seeds under two moisture conditions (7 and 9% dry basis) was investigated. The extraction assays were performed using a stirred batch system, thermostated at 50 °C, using n-hexane as solvent. The data obtained were fitted to a modified diffusion model in order to represent the extraction kinetics. The model took into account a washing and a diffusive step. Fitting parameters were compared statistically for both moisture conditions. The oil yield increased with the extraction time in both cases, although the oil was released at different rates. A comparison of the parameters showed that both the portion extracted in the washing phase and the effective diffusion coefficient were moisture-dependent. The effective diffusivities were 2.81 10 -12 and 8.06 10 -13 m 2 s -1 for moisture contents of 7% and 9%, respectively.
The Canadian Journal of Chemical Engineering, 2015
In this work the kinetics of oil extraction from spring canola seeds subjected to a hydrothermal ... more In this work the kinetics of oil extraction from spring canola seeds subjected to a hydrothermal pretreatment with direct steam (393 K, 5 min) was studied. The differences between the seed internal structure generated by the application of this pretreatment and that of the untreated sample (ground sample) were observed by scanning electron microscopy. Oil from both samples was extracted with hexane at different times and temperatures using a stirred batch system. Oil yield increased up to 46 % due to the hydrothermal treatment. A model was proposed to explain the oil extraction process from hydrothermally pretreated and untreated canola seeds, taking into account two main mechanisms: a washing process of the surface oil from the seed, and a diffusion process. Parameters of the model were fitted, and values of the oil fraction extracted during the washing step (0.27 and 0.50 for untreated and hydrothermally treated canola seeds, respectively) and the effective diffusion coefficient (...
ABSTRACT Dietary fibre enrichment of white bread with inulin-rich carbohydrate (IRC) powder extra... more ABSTRACT Dietary fibre enrichment of white bread with inulin-rich carbohydrate (IRC) powder extracted from Jerusalem artichoke tubers (IRC-J) was studied. Previously, it was shown that this IRC-J powder had higher prebiotic activity score than a commercial chicory inulin (IRC-C) powder, used for comparison. For bread making, 2.5 and 5.0 g of either IRC-J or IRC-C were added to 100 g of wheat flour, and the effects on dough viscoelastic properties and bread quality properties were analyzed, relative to a control sample (no IRC added). The lowest IRC concentration of both fibres had no significant effect on the elastic modulus (G’) of the dough, but the highest IRC level decreased G’, with a stronger effect of IRC-J. This was attributed to disruption of the starch-gluten matrix due to fibre replacement of flour. In turn, this was thought to impair gas retention (known as diluting effect), resulting in the observed decrease of bread specific volume and Cell/Total Area ratio, and the increase in crumb hardness and chewiness. IRC addition also had a significant effect on crumb and crust colour, and other crumb grain features. These effects were more significant at the highest IRC concentration of both fibres. Breads with 5.0 g of IRC-J were significantly darker, flatter, and more humid. All the sensory attributes of breads with 0 (control sample), 2.5 g IRC-J, and 2.5 g IRC-C were acceptable, and no significant differences were found between the three samples, in any of the attributes.
Frutos de Ligustrum lucidum Ait y Ligustrum sinense Lour fueron cosechados en Olavarría (provinci... more Frutos de Ligustrum lucidum Ait y Ligustrum sinense Lour fueron cosechados en Olavarría (provincia de Buenos Aires, Argentina) y sus semillas separadas en forma manual. Las semillas se agotaron con n-hexano, obteniendo los aceites crudos con rendimientos del 8,7-10% y 10,7 % (base seca), respectivamente. Los aceites crudos se examinaron en sus características fisicoquímicas (Índice de refracción: 1,4647 y 1,4640 (a 25 o C), Indice de iodo: 93,7 y 88,8, Indice de saponificación: 167 y 154, insaponificable: 11 y 18 %, Indice de acidez: 4,8 y 9,2 (mgKOH/g) respectivamente. El análisis por cromatografía gaseosa de los ésteres metílicos reveló alto porcentaje de ácido oleico (57,8 y 51,1%), alrededor de un 25,1 y 29,6 % de ácidos saturados, respectivamente, predominando el ácido palmítico, pero con un significativo contenido de ácidos de más de 18 átomos de carbono. Las harinas residuales de extracción contenían baja proporción de proteína cruda y de lisina disponible. Se informan valores de fósforo total y de ácido fítico, cenizas, calcio, fibra cruda, hidratos de carbono.
ABSTRACT In this work a statistical method of comparison was used in order to compare the paramet... more ABSTRACT In this work a statistical method of comparison was used in order to compare the parameters of a modified diffusion model representing the kinetics of canola oil and tocopherol extraction. The model takes into account an initial stage where solvent removes the oil from the surface of the ground seed by washing. Kinetic tests were carried out in a batch extractor at different temperatures (from 25 to 60 °C) using hexane as solvent. Tocopherol concentration in the extracted oil was determined by HPLC.The parameter comparison showed that the portion extracted during the washing stage was only temperature-dependent in the case of tocopherol extraction, whereas the effective diffusion coefficients were temperature-dependent in oil and tocopherol extraction. The diffusivities ranged from 1.3 × 10−12 to 3.0 × 10−12 m2 s−1 and from 1.6 × 10−12 to 2.3 × 10−12 m2 s−1 for oil and tocopherol extraction, respectively. The oil and tocopherol extraction activation energy was 19.1 kJ mol−1 and 8.1 kJ mol−1, respectively.
Pectinase-assisted solvent extraction of oil and total tocopherol from sunflower hybrids with dif... more Pectinase-assisted solvent extraction of oil and total tocopherol from sunflower hybrids with different structural characteristics was studied by means of laboratory tests carried out in a stirred batch extractor at 50 °C. From the oil yield results obtained for the two hybrids studied, black-hull (P20) and striped-hull hybrids (ACA 884), it could be observed that oil was extracted at different rates in both hybrids. Analyzing the performance data versus time in the control samples, ACA 884 oil was released more easily and remained invariant with time, whereas for P20 the extraction was slower and the maximum value was reached at 60 min. The fiber wall structure collapsed by the enzymatic action, improving oil release and allowing a faster extraction. The efficiency of the treatment was measured in terms of the percentage of increase in oil yield compared with the control samples. It was observed that in hybrid ACA 884 the mean increases were not significantly different (p = 0.9295) over time (4.12% d.b.). Hybrid P20 showed a significant increase in the percentage of oil yield (p = 0.0001) at 10 min (10.85% d.b.), and then it remained virtually constant over time (4.89% d.b.). The black-hull hybrid (P20) presented significant differences in fatty acid composition due to the enzymatic action. Pectinase treatment was highly effective in the tocopherol extraction from hybrid P20 (p < 0.001), obtaining a 32.3% increase on average. The maximum values were 662 and 220 lg g dried ground seed À1 at 60 and 120 min for black-hull and stripedhull hybrids, respectively. The enzymatic treatment effectively produced an increase in oil and tocopherol yields for the black-hull hybrid.
In the present work the in vitro prebiotic activity of inulin-rich carbohydrates using Lactobacil... more In the present work the in vitro prebiotic activity of inulin-rich carbohydrates using Lactobacillus paracasei as probiotic microorganism was determined. With this purpose, inulin-rich carbohydrates samples from Jerusalem artichoke tubers stored at 4-5 °C during different times along an overall period of 8 months were extracted. Extraction yield, inulin content and average polymerization degree of inulin-rich carbohydrates samples were also determined. For all samples, extraction yield and inulin content decreased with storage time. In particular, inulin content exhibited values within the range of commercial food grade inulin (≥85%). Average polymerization degree values decreased with storage time ranging from 12.1 to 8.3. The in vitro prebiotic activity of inulinrich carbohydrates samples was assessed using a prebiotic activity score which considered the growing ratio relative to glucose of L. paracasei as well as of the enteric bacteria Escherichia coli when such carbohydrates were used as C source. Inulin-rich carbohydrates extracted from tubers cold-stored during 4 months showed the highest prebiotic activity score, even higher than the corresponding to a commercial food grade inulin, indicating that this sample should be used as a prebiotic food ingredient, representing a potential alternative to the available commercial inulin obtained from chicory roots.
The Canadian Journal of Chemical Engineering, 2014
The aim of the present work was to determine the optimum operating conditions in hydrothermal pre... more The aim of the present work was to determine the optimum operating conditions in hydrothermal pretreatments applied to canola seeds. The effect of these pretreatments on the canola oil extraction yield and quality was evaluated. Samples were characterized by proximate analysis. Acidity and peroxide value were studied as parameters for the determination of oil quality. Seeds were exposed to direct steam contact in an autoclave. Pretreatments were carried out using different temperatures (100, 120 and 130 8C), exposition times (5, 15 and 30 min) and seed granulometry (ground seeds, with a particle size in a range from 0.420 to 1.000 mm; broken seeds, with a particle size ranging from 1.000 to 1.410 mm, and entire seeds). After each hydrothermal pretreatment, oil extraction was carried out by the Soxhlet method (hexane). The Taguchi method was followed in order to explore the optimum operating conditions by using an L9 experimental design, and select the most favourable levels of each variable. Initial oil content was 44.2% dry basis (db). The selected optimum experiment, using a temperature of 120 8C, a time of 5 min and broken seeds, generated an oil yield increase of 20% compared with non-hydrothermally treated seeds, whereas quality parameters remained within the accepted values for trade standards.
As part of a study to characterise and examine the use of wild sunflower species (Helianthus peti... more As part of a study to characterise and examine the use of wild sunflower species (Helianthus petiolaris Nutt), some physical properties and morphological characteristics of seeds from different locations in Argentina were determined. The oil content ranged between 27% and 30% (wb) and the moisture content varied from 8Á9% to 10Á4%. The average length, width, and thickness of the seed, measured with a micrometer, were 4Á5, 2Á02, and 1Á2 mm, respectively. The calculated mean values of seed equivalent diameter, surface area, and sphericity were 2Á25 mm, 16Á2 mm 2 , and 0Á48, respectively. The bulk and true densities measured with a hectolitre tester and by picnometry, respectively, were 350 and 399 kg/m 3 . The angle of repose ranged between 28Á61 and 30Á21. The morphological characteristics as well as the hull thickness and percentage were also evaluated by scanning electron microscopy. The hull thickness and percentage had mean values 0Á07 mm and 21%, respectively. Achenes presented straight and double hairs and a morphological study showed a pericarp structure with an amorphous and lignified fibre layer and air cavities between the inner parenchyma and the cotyledon.
The aim of this work was to study the patterns of the accumulation of carbohydrates, organic acid... more The aim of this work was to study the patterns of the accumulation of carbohydrates, organic acids, and minerals at different development stages of Hexachlamys edulis fruit for its evaluation as a source of health-promoting compounds, which is necessary in order to be included in the Argentine Food Code. Additionally, the obtained results will allow for deciding the optimal time for consumption to receive a better flavour and a good contribution of the nutrients evaluated. The succinic acid concentration (the major organic acid) was high in unripe fruit (112.33 mg/g of the dry weight), then decreased to a minimum in medium ripe and ripe fruit (92.48 to 99.43 mg/g of the dry weight,), to increase again in overripe fruit (115.65 mg/g of the dry weight,). Sucrose increased significantly from 21.20 mg/g of the dry weight in unripe fruit to a maximum of 82.53 mg/g of the dry weight in ripe fruit. Glucose increased significantly from 95.59 mg/g of the dry weight in unripe fruit to a maxim...
European Journal of Lipid Science and Technology, 2018
The aim of this work is to analyze the effect of moisture content of sunflower expanded material ... more The aim of this work is to analyze the effect of moisture content of sunflower expanded material on the quality of the extracted oil by determining its wax, phospholipids, and tocopherol content and composition. Sunflower oil extraction is carried out in a batch extractor at 50 °C using hexane and three moisture levels (5.65, 12.40, and 18.92% dry basis). The increasing moisture content causes an increment in both oil yield and total amount of minor compounds. The total wax content ranges between 808 and 1118 ppm, the wax fraction is composed mainly of esters of between 44 and 58 carbon atoms (>67%), and the distribution does not change with the moisture content. In all the experiments, α‐ and β‐tocopherols and β‐tocotrienol are detected, with the level of α‐tocopherol being higher than 93% and easier to extract at 12.40% moisture. Furthermore, the phospholipids content in the oil increases with moisture content but maintains its profile composition. The obtained results can be e...
Journal of the American Oil Chemists' Society, 2004
Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolari... more Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolaris Nutt and their comparison with those from cultivated sunflower (H. annuus) were performed. Seeds from indigenous populations of H. petiolaris were harvested in Argentina in different years. The analytical parameters studied were as follows: (i) FA profile, PV, p-anisidine value, oxidative stability, phosphorus and phospholipid content, tocopherols, polar compounds, and waxes in the extracted oils; and (ii) moisture, ash, crude fiber, metals, sugars, urease activity, starch, protein, available lysine, neutral detergent fiber, acid detergent fiber, lignin, gross energy, and amino acid content in the residual meals. The products from wild sunflower seed, which yielded 27-30% oil by solvent extraction, showed some characteristics similar to the commercial products. Nevertheless, the oil had lower quality and stability owing to the high unsaturation levels and lower concentrations of antioxidant components, and the meal had a lower protein content. The phospholipid content was significantly lower than in industrial crude sunflower oils. Most of the important parameters in the meal such as available lysine, gross energy, and digestibility compared favorably with those for cultivated sunflower meals. The results showed the potential for using these meals for animal feed.
Journal of The American Oil Chemists Society, 2004
Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolari... more Chemical characterizations of oils and meals from the wild sunflower species Helianthus petiolaris Nutt and their comparison with those from cultivated sunflower (H. annuus) were performed. Seeds from indigenous populations of H. petiolaris were harvested in Argentina in different years. The analytical parameters studied were as follows: (i) FA profile, PV, p-anisidine value, oxidative stability, phosphorus and phospholipid content, tocopherols, polar compounds, and waxes in the extracted oils; and (ii) moisture, ash, crude fiber, metals, sugars, urease activity, starch, protein, available lysine, neutral detergent fiber, acid detergent fiber, lignin, gross energy, and amino acid content in the residual meals. The products from wild sunflower seed, which yielded 27–30% oil by solvent extraction, showed some characteristics similar to the commercial products. Nevertheless, the oil had lower quality and stability owing to the high unsaturation levels and lower concentrations of antioxidant components, and the meal had a lower protein content. The phospholipid content was significantly lower than in industrial crude sunflower oils. Most of the important parameters in the meal such as available lysine, gross energy, and digestibility compared favorably with those for cultivated sunflower meals. The results showed the potential for using these meals for animal feed.
The temperature-dependent diffusion coefficients of interstitial hydrogen, deuterium, and tritium... more The temperature-dependent diffusion coefficients of interstitial hydrogen, deuterium, and tritium in nickel are computed using transition state theory. The coefficient of thermal expansion, the enthalpy and entropy of activation, and the pre-exponential factor of the diffusion coefficient are obtained from ab initio total energy and phonon calculations including the vibrations of all atoms. Numerical results reveal that diffusion between octahedral interstitial sites occurs along an indirect path via the metastable tetrahedral site and that both the migration enthalpy and entropy are strongly temperature dependent. However, the migration enthalpy and entropy are coupled so that the diffusion coefficient is well described by a constant activation energy, i.e., D = D 0 exp͓−Q / ͑RT͔͒, with Q = 45.72, 44.09, and 43.04 kJ/ mol and D 0 = 3.84ϫ 10 −6 , 2.40ϫ 10 −6 , 1.77 ϫ 10 −6 m 2 s −1 for H, D, and T, respectively. The diffusion of deuterium and tritium is computed to be slower than that of hydrogen only at temperatures above 400 K. At lower temperatures, the order is reversed in excellent agreement with experiment. The present approach is applicable to atoms of any mass as it includes the full coupling between the vibrational modes of the diffusing atom with the host lattice.
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Papers by Ethel Perez