163 research outputs found
Influence of pH on colour and iron content of peptide fractions obtained from bovine Hb concentrate hydrolysates
The effect of pH on colour and iron content (Fe) of peptide fractions obtained from bovine haemoglobin concentrate (BHC) hydrolysates was studied. Four hydrolysates were obtained using three enzymes: Protex- 6-L (P), Fungal?Protease?Concetrate (FC) and Flavourzyme (F). BHC and its hydrolysates (P, FC, P + F, FC + F) were fractioned at pH 4.5, 7.0 and 9.5. Solubility and Fe from different fractions were measured. Correlations between CIELAB colour parameters and Fe from different fractions were analysed. The colour from different fractions varied from red to yellow (a* and b* positives). Lightness values (L*) ranged from twenty-four to seventy. FC4.5 and FC + F4.5 fractions were the clearest and yellow (higher L*, b*, h), while BHC9.5 and P + F9.5 fractions had the lowest values of L*, b* and h. There was an inverse linear relationship between b* and L* parameters and Fe from fractions. This relationship could be associated with the pH of extraction. As pH increases Fe significantly increases and lower b* and L* values were obtained.Fil: Cian, Raúl Esteban. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Drago, Silvina Rosa. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: González, Rolando J.. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología de los Alimentos; Argentin
Physicochemical properties and structural characteristics of whole grain Oryza sativa L. with different treatments
[EN] Physicochemical properties and structural characteristics of whole rice flours with different treatments
(soaking, germination and extrusion cooking) were studied. Water solubility, water absorption, crystallinity,
adsorption isotherms (BET and GAB models), and glass transition temperature of the samples were determined.
Water solubility and water absorption were enhanced by extrusion cooking process (3.17 4.98 vs.
24.1 53.76 g/100 g and 2.77 3.05 vs. 4.46 7.04 ml/g, respectively), but crystallinity was decreased (30 33 vs.
4 16%). Adsorption isotherms showed that extruded samples exhibited higher equilibrium moisture content
as compared with their corresponding non-extruded samples (5.0 19.2 vs. 4.0 16.1 g water/g solids). There
were no changes in glass transition temperature values in the studied moisture range (3.8 16 g/100 g). These
results allow the correct use of whole rice flours with different treatments in foods and also contributed to the
knowledge of stabilization of the productsThe author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This work was partially financed by ANPCYT (PICT 1105) and ERASMUS MUNDUS ACTION 2 ARCOIRIS Fellowship.Albarracin, M.; Talens Oliag, P.; Martínez Navarrete, N.; González, RJ.; Drago, SR. (2016). Physicochemical properties and structural characteristics of whole grain Oryza sativa L. with different treatments. Food Science and Technology International. 22(4):1-10. doi:10.1177/1082013215600078S110224Albarracín, M., José González, R., & Drago, S. R. (2015). Soaking and extrusion effects on physicochemical parameters, phytic acid, nutrient content and mineral bio-accessibility of whole rice grain. International Journal of Food Sciences and Nutrition, 66(2), 210-215. doi:10.3109/09637486.2014.986070Björck, I., & Asp, N.-G. (1983). The effects of extrusion cooking on nutritional value — A literature review. Journal of Food Engineering, 2(4), 281-308. doi:10.1016/0260-8774(83)90016-xBrunauer, S., Deming, L. S., Deming, W. E., & Teller, E. (1940). On a Theory of the van der Waals Adsorption of Gases. Journal of the American Chemical Society, 62(7), 1723-1732. doi:10.1021/ja01864a025Donkor, O. N., Stojanovska, L., Ginn, P., Ashton, J., & Vasiljevic, T. (2012). Germinated grains – Sources of bioactive compounds. Food Chemistry, 135(3), 950-959. doi:10.1016/j.foodchem.2012.05.058Gonzalez, R. J., De Greef, D. M., Torres, R. L., Borras, F. S., & Robutti, J. (2004). Effects of endosperm hardness and extrusion temperature on properties of products obtained with grits from two commercial maize cultivars. LWT - Food Science and Technology, 37(2), 193-198. doi:10.1016/j.lwt.2003.07.004Gonzalez, R., Drago, S., Torres, R., & De Greef, D. (2013). Extrusion Cooking of Cereal-Based Products. Contemporary Food Engineering. doi:10.1201/b15246-13González, R. J., Pastor Cavada, E., Vioque Peña, J., Torres, R. L., De Greef, D. M., & Drago, S. R. (2013). Extrusion Conditions and Amylose Content Affect Physicochemical Properties of Extrudates Obtained from Brown Rice Grains. International Journal of Food Science, 2013, 1-8. doi:10.1155/2013/584148Herawat, H., Kusnandar, F., Adawiyah, D. R., Budijanto, S., & Rahman, M. S. (2014). Thermal characteristics and state diagram of extruded instant artificial rice. Thermochimica Acta, 593, 50-57. doi:10.1016/j.tca.2014.08.017Jones, J. M., & Engleson, J. (2010). Whole Grains: Benefits and Challenges. Annual Review of Food Science and Technology, 1(1), 19-40. doi:10.1146/annurev.food.112408.132746Kim, H. Y., Hwang, I. G., Kim, T. M., Woo, K. S., Park, D. S., Kim, J. H., … Jeong, H. S. (2012). Chemical and functional components in different parts of rough rice (Oryza sativa L.) before and after germination. Food Chemistry, 134(1), 288-293. doi:10.1016/j.foodchem.2012.02.138Lowry, R. R., & Tinsley, I. J. (1976). Rapid colorimetric determination of free fatty acids. Journal of the American Oil Chemists’ Society, 53(7), 470-472. doi:10.1007/bf02636814Matveev, Y. (2000). The plasticizing effect of water on proteins, polysaccharides and their mixtures. Glassy state of biopolymers, food and seeds. Food Hydrocolloids, 14(5), 425-437. doi:10.1016/s0268-005x(00)00020-5Perdon, A., Siebenmorgen, T. J., & Mauromoustakos, A. (2000). Glassy State Transition and Rice Drying: Development of a Brown Rice State Diagram. Cereal Chemistry Journal, 77(6), 708-713. doi:10.1094/cchem.2000.77.6.708ROOS, Y., & KAREL, M. (1991). Plasticizing Effect of Water on Thermal Behavior and Crystallization of Amorphous Food Models. Journal of Food Science, 56(1), 38-43. doi:10.1111/j.1365-2621.1991.tb07970.xRuiz-Ruiz, J., Martínez-Ayala, A., Drago, S., González, R., Betancur-Ancona, D., & Chel-Guerrero, L. (2008). Extrusion of a hard-to-cook bean (Phaseolus vulgaris L.) and quality protein maize (Zea mays L.) flour blend. LWT - Food Science and Technology, 41(10), 1799-1807. doi:10.1016/j.lwt.2008.01.005SIU, G. M., & DRAPER, H. H. (1978). A SURVEY OF THE MALONALDEHYDE CONTENT OF RETAIL MEATS AND FISH. Journal of Food Science, 43(4), 1147-1149. doi:10.1111/j.1365-2621.1978.tb15256.xSun, Z., Yang, W., Siebenmorgen, T., Stelwagen, A., & Cnossen, A. (2002). Thermomechanical Transitions of Rice Kernels. Cereal Chemistry Journal, 79(3), 349-353. doi:10.1094/cchem.2002.79.3.349Timmermann, E. O. (2003). Multilayer sorption parameters: BET or GAB values? Colloids and Surfaces A: Physicochemical and Engineering Aspects, 220(1-3), 235-260. doi:10.1016/s0927-7757(03)00059-1Tovar, J., Bjoerck, I. M., & Asp, N. G. (1990). Starch content and .alpha.-amylolysis rate in precooked legume flours. Journal of Agricultural and Food Chemistry, 38(9), 1818-1823. doi:10.1021/jf00099a00
Harina de maíz para tortillas: Efectos de la dureza del endospermo y de las variables de extrusión
Dos tipos de maíz, con distinta dureza de endospermo fueron utilizados para analizar el efecto de la extrusión sobre las propiedades fisicoquímicas de la harina extrudida y su aptitud para hacer tortillas. La extrusión se llevó a cabo con un extrusor Brabender monotornillo y la metodología de respuesta fue utilizada para analizar los efectos de la humedad de la harina (rango: 27-35%) y la temperatura de extrusión (rango: 114-150ºC) sobre el almidón dañado, la absorción de agua, la solubilidad en agua, la consistencia de retrogradación amilográfica y también sobre los atributos sensoriales de la tortilla obtenida con la harina extrudida. El efecto de la dureza del endospermo fue significativo y el uso de maíz de endospermo blando es recomendado. Las condiciones de extrusión más adecuadas serían aquellas que permiten alcanzar grados de cocción intermedios, los cuales pueden ser obtenidos en las siguientes condiciones de temperatura y humedad de la harina a extrudir: 114ºC-27%, 132ºC-27%, 132ºC-31%, y 150ºC-35%.Fil: Haller, Darío. No especifíca;Fil: González, Rolando J.. No especifíca;Fil: Drago, Silvina Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Torres, Roberto L.. No especifíca;Fil: De Greef, Dardo M.. No especifíca
Harina de maíz para tortillas: Efectos de la dureza del endospermo y de las variables de extrusión
Dos tipos de maíz, con distinta dureza de endospermo fueron utilizados para analizar el efecto de la extrusión sobre las propiedades fisicoquímicas de la harina extrudida y su aptitud para hacer tortillas. La extrusión se llevó a cabo con un extrusor Brabender monotornillo y la metodología de respuesta fue utilizada para analizar los efectos de la humedad de la harina (rango: 27-35%) y la temperatura de extrusión (rango: 114-150ºC) sobre el almidón dañado, la absorción de agua, la solubilidad en agua, la consistencia de retrogradación amilográfica y también sobre los atributos sensoriales de la tortilla obtenida con la harina extrudida. El efecto de la dureza del endospermo fue significativo y el uso de maíz de endospermo blando es recomendado. Las condiciones de extrusión más adecuadas serían aquellas que permiten alcanzar grados de cocción intermedios, los cuales pueden ser obtenidos en las siguientes condiciones de temperatura y humedad de la harina a extrudir: 114ºC-27%, 132ºC-27%, 132ºC-31%, y 150ºC-35%.Fil: Haller, Darío. No especifíca;Fil: González, Rolando J.. No especifíca;Fil: Drago, Silvina Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Torres, Roberto L.. No especifíca;Fil: De Greef, Dardo M.. No especifíca
Dynamical speckles patterns of action potential transmission effects in squid giant axon membrane.
Undoubtedly the most important result of the investigations in physiology and biophysics was the discovery of the electrochemical mechanism of propagation of the action potential in nerves that was made by Hodgkin and Huxley during the first half of the past century. Since some decades ago diverse experiments about the electro optical properties of the axon membrane there was published using the most diverse optical experimental ‘procedures POT 6-10’. In this paper some results of a dynamical speckle technique applied for obtaining microscopic images of a section of a squid giant axon membrane during the activation by electrical impulses and his digital process are presented.CAPESFAPES
Óptimos económicos en corderos pelibuey engordados en corral
Los óptimos técnico (OT) y económico (OE) fueron estimados durante ocho semanas en 24 corderos Pelibuey machos (PVI 20+-0.52 k y edad 75+-15 d). Los valores del OT para alimentación y número de semanas fueron 107.40 k y 34.3, con ganancias de 1 147.61, y los del OE fueron 95.1 k y 34.26, con ganancias de 1 148.13. El peso máximo in vivo no necesariamente significa un máximo ingreso neto
The Atacama Cosmology Telescope: Dynamical Masses and Scaling Relations for a Sample of Massive Sunyaev-Zel'dovich Effect Selected Galaxy Clusters
We present the first dynamical mass estimates and scaling relations for a
sample of Sunyaev-Zel'dovich effect (SZE) selected galaxy clusters. The sample
consists of 16 massive clusters detected with the Atacama Cosmology Telescope
(ACT) over a 455 sq. deg. area of the southern sky. Deep multi-object
spectroscopic observations were taken to secure intermediate-resolution
(R~700-800) spectra and redshifts for ~60 member galaxies on average per
cluster. The dynamical masses M_200c of the clusters have been calculated using
simulation-based scaling relations between velocity dispersion and mass. The
sample has a median redshift z=0.50 and a median mass M_200c~12e14 Msun/h70
with a lower limit M_200c~6e14 Msun/h70, consistent with the expectations for
the ACT southern sky survey. These masses are compared to the ACT SZE
properties of the sample, specifically, the match-filtered central SZE
amplitude y, the central Compton parameter y0, and the integrated Compton
signal Y_200c, which we use to derive SZE-Mass scaling relations. All SZE
estimators correlate with dynamical mass with low intrinsic scatter (<~20%), in
agreement with numerical simulations. We explore the effects of various
systematic effects on these scaling relations, including the correlation
between observables and the influence of dynamically disturbed clusters. Using
the 3-dimensional information available, we divide the sample into relaxed and
disturbed clusters and find that ~50% of the clusters are disturbed. There are
hints that disturbed systems might bias the scaling relations but given the
current sample sizes these differences are not significant; further studies
including more clusters are required to assess the impact of these clusters on
the scaling relations.Comment: 15 pages, 4 figures. Accepted for publication in The Astrophysical
Journal; matches published version. Full Table 8 with complete spectroscopic
member sample available in machine-readable form in the journal site and upon
request to C. Sif\'o
The Atacama Cosmology Telescope: Physical Properties and Purity of a Galaxy Cluster Sample Selected via the Sunyaev-Zel'dovich Effect
We present optical and X-ray properties for the first confirmed galaxy
cluster sample selected by the Sunyaev-Zel'dovich Effect from 148 GHz maps over
455 square degrees of sky made with the Atacama Cosmology Telescope. These
maps, coupled with multi-band imaging on 4-meter-class optical telescopes, have
yielded a sample of 23 galaxy clusters with redshifts between 0.118 and 1.066.
Of these 23 clusters, 10 are newly discovered. The selection of this sample is
approximately mass limited and essentially independent of redshift. We provide
optical positions, images, redshifts and X-ray fluxes and luminosities for the
full sample, and X-ray temperatures of an important subset. The mass limit of
the full sample is around 8e14 Msun, with a number distribution that peaks
around a redshift of 0.4. For the 10 highest significance SZE-selected cluster
candidates, all of which are optically confirmed, the mass threshold is 1e15
Msun and the redshift range is 0.167 to 1.066. Archival observations from
Chandra, XMM-Newton, and ROSAT provide X-ray luminosities and temperatures that
are broadly consistent with this mass threshold. Our optical follow-up
procedure also allowed us to assess the purity of the ACT cluster sample.
Eighty (one hundred) percent of the 148 GHz candidates with signal-to-noise
ratios greater than 5.1 (5.7) are confirmed as massive clusters. The reported
sample represents one of the largest SZE-selected sample of massive clusters
over all redshifts within a cosmologically-significant survey volume, which
will enable cosmological studies as well as future studies on the evolution,
morphology, and stellar populations in the most massive clusters in the
Universe.Comment: 20 pages, 15 figures, 6 tables. Accepted for publication in ApJ.
Higher resolution figures available at:
http://peumo.rutgers.edu/~felipe/e-prints
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