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1.
J Sci Food Agric ; 98(8): 3109-3118, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29210447

RESUMEN

BACKGROUND: This study aimed to concentrate dietary fiber (DF) from peach (Prunus persica) juice by-product (PJBP), to improve its functional properties, and its polyphenols bioavailability. The dietary fiber concentrates (DFCs) were obtained from PJBP using water/ethanol treatments (100:0, 20:80, 50:50, 80:20, and 0:100, v/v) at 1:5 ratio (wet weight/solvent, w/v) for 5 and 20 min at 21 °C. RESULTS: All treatments concentrated condensed tannins, total and insoluble DF, with the highest content found with 100% H2 O treatment. The major polyphenols of DFC were 4-O-caffeoylquinic, chlorogenic, and 1,5-di-O-caffeoylquinic acids. Water and oil retention capacity and maximum glucose diffusion rate were improved mainly with 100% H2 O treatment. Healthy rats were fed with a standard diet supplemented with 8% of PJBP, DFC obtained with 100% H2 O for 5 min, or DFC obtained with 20% EtOH for 5 min. Gastrointestinal digesta weight and viscosity were increased in animals supplemented with 100% H2 O DFC. Moreover, the urinary excretion of polyphenol metabolites, mainly glucuronide and sulfate conjugates, was increased with this treatment, indicating a greater bioavailability of PJBP polyphenols, which was associated with an increased dietary fiber porosity. CONCLUSION: Water treatment could be used to potentiate PJBP functional properties and polyphenols bioavailability. © 2017 Society of Chemical Industry.


Asunto(s)
Fibras de la Dieta/análisis , Jugos de Frutas y Vegetales/análisis , Fenoles/química , Preparaciones de Plantas/química , Preparaciones de Plantas/metabolismo , Prunus persica/química , Animales , Disponibilidad Biológica , Fibras de la Dieta/metabolismo , Digestión , Frutas/química , Frutas/metabolismo , Masculino , Fenoles/metabolismo , Prunus persica/metabolismo , Ratas , Ratas Wistar , Residuos/análisis
2.
Int J Biol Macromol ; 277(Pt 4): 134508, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39106932

RESUMEN

The aim of this work was to investigate the effects of ultrasonic treatment during soaking of potatoes on the physicochemical properties of starches obtained after 16 weeks of germination. The ultrasonic treatment showed a direct correlation between sprout length and ultrasonic time. The protein content decreased from 0.63 to 0.38 % and the fat content decreased significantly from 0.31 to 0.01 % after germination. The amylose content changed depending on the ultrasonic treatment, and increased from 36.27 to 40.92 % after 16 weeks of germination, which was related to the amylopectin debranching and the duration of the ultrasonic treatment. X-ray diffraction showed that the nanocrystals with hexagonal structure were not affected by the germination and the duration of ultrasonic treatment. Scanning electron microscopy showed that the surface of the starch granules was not affected by the enzymatic treatment. The sprouted potato starch resulted in films with better tensile strength and lower water vapor permeability (WVP) compared to the native potato starch films. In addition, the films produced with ultrasound stimulated potato starch exhibited better properties (high strength and low permeability), which is desirable when it comes to controlling moisture exchange between a food product and the surrounding atmosphere.


Asunto(s)
Fenómenos Químicos , Películas Comestibles , Germinación , Solanum tuberosum , Almidón , Solanum tuberosum/química , Almidón/química , Permeabilidad , Ondas Ultrasónicas , Amilosa/química , Vapor , Resistencia a la Tracción , Difracción de Rayos X
3.
J Biomed Mater Res B Appl Biomater ; 112(10): e35484, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39295140

RESUMEN

The aim of this work is to investigate the changes in the physicochemical properties of hydroxyapatite (HAp) extracted from horse humerus bones of different ages (1, 3, 6, and 8 years) subjected to low temperature calcination (600°C). Thermal analysis revealed significant mass loss due to water, collagen, organic compounds, carbonates, and age-related magnesium out-diffusion. Higher fat content in older bones contributed to increased mass loss. Phosphorus content remained constant across age groups, while calcium and sodium showed age-related fluctuations. Magnesium levels decreased with age, emphasizing its importance for early bone development. The Ca/P ratio deviated from the stoichiometric values due to additional ions from biogenic sources. Infrared spectroscopy identified functional groups in carbonated HAp, with changes observed before and after calcination. The full width at half maximum (FWHM) of the 961 cm-1 band decreased with age, indicating improved crystalline quality. The molar absorption coefficients provided information on the changes in molecular concentration and emphasized the differences between the age groups. X-ray analysis revealed nanocrystalline HAp in all samples, with crystallite size increasing with age. Rietveld analysis showed that the lattice parameters were affected by the presence of organic material, but the lattice constants remained stable, confirming high crystallinity independent of age. TEM analysis confirmed nanocrystalline structures, with crystallite size increasing with age. SEM images showed the characteristic porosity of calcined HAp, with particle size correlating positively with age. Calcination at 600°C preserved the nanoscale properties and microcrystal formation. Raman spectroscopy confirmed the identity of HAp, with FWHM variations indicating age-related changes in crystalline quality. EHAp1 showed increased FWHM, indicating lower crystalline quality and increased trace element content.


Asunto(s)
Durapatita , Húmero , Animales , Caballos , Durapatita/química , Húmero/química , Frío , Envejecimiento
4.
J Food Sci ; 89(10): 6601-6615, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39289790

RESUMEN

This study aimed to investigate the effects of acid or alkali modification of isolated cassava starch (ICS) on its physicochemical properties. Acetic acid concentrations of 5%, 10%, and 20% v/v (0.87, 1.73, and 3.46 M, respectively) and calcium hydroxide concentrations of 0.15%, 0.20%, and 0.30% w/w (0.02, 0.025, and 0.04 M, respectively) were tested independently and compared with untreated isolated starch. The scanning electron microscope (SEM) shows starches with polyhedral and semispherical shapes; these modifications do not change the surface of the starch granules. Nanocrystals with orthorhombic crystal structure were extracted from ICS. Transmission electron microscopy (TEM) shows crystallites with a size (two-dimensional) of 20 ± 5 nm in length and 10 ± 2 nm in width and reveals that this starch contains nanocrystals with orthorhombic crystal structure. The X-ray patterns show that these nanocrystals are unaffected by acidic or alkaline treatments. The Ca+2 and CH3COO- ions do not interact with these nanocrystals. The alkaline treatment only affects the gelatinization temperature at a Ca(OH)2 concentration of 0.30%. Low concentrations of acidic and alkaline treatments affect the ability of cassava starch to absorb water and reduce the peak and final viscosity. The infrared spectra show that the modifications lead to C-H and C═C bond formations. ICS-B 0.30 can modify the amorphous regions of the starch, and the acid treatment leads to acetylation, which was confirmed by the presence of an IR band at 1740 cm-1.


Asunto(s)
Manihot , Reología , Almidón , Manihot/química , Almidón/química , Concentración de Iones de Hidrógeno , Difracción de Rayos X , Microscopía Electrónica de Rastreo , Ácido Acético/química , Nanopartículas/química , Hidróxido de Calcio/química , Viscosidad , Microscopía Electrónica de Transmisión
5.
Chemosphere ; 366: 143535, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39413931

RESUMEN

In this study, the adsorption capacity of bio-hydroxyapatite (Bio-HAp) from devilfish for the removal of F- and Cd(II) from aqueous solutions was investigated. This material was synthesized according to a 2FI factorial experimental design by varying the extraction conditions for Bio-HAp, including the type of pretreatment (alkaline and peroxide), the calcination temperature from 550 to 850 °C, and the sonication process. The maximum adsorption capacities were 8.48 and 83.56 mg g-1 for F- and Cd(II), respectively. Statistical analysis showed the importance of the type of pretreatment, temperature, and sonication for adsorption. The predicted optimal conditions were Bio-HAp extracted from bone with peroxide pretreatment, calcination at 550 °C and sonication. The surface of the Bio-HAp was found to be mesoporous and basic in character. TGA, FT-IR and SEM-EDS characterizations confirmed the presence of F- and Cd(II) on the Bio-HAp surface and confirmed the adsorption mechanisms by electrostatic forces, ion exchange, and chemisorption. The Praunitz-Rake model of adsorption isotherm showed better agreement with the equilibrium adsorption data of F- and Cd(II) at pH 7. Furthermore, photodegradation experiments showed 100% degradation methylene blue (MB) under natural sunlight. This study indicates an effective photodegradation process, suggesting high adsorption capacity of the samples. The use of devilfish as an adsorbent promises to be a viable and sustainable option for the removal of fluoride and cadmium from water, and for use in photodegradation experiments.


Asunto(s)
Cadmio , Durapatita , Fluoruros , Contaminantes Químicos del Agua , Adsorción , Durapatita/química , Animales , Cadmio/química , Cadmio/aislamiento & purificación , Contaminantes Químicos del Agua/química , Fluoruros/química , Decapodiformes/química , Purificación del Agua/métodos , Catálisis , Concentración de Iones de Hidrógeno
6.
Int J Biol Macromol ; 282(Pt 2): 136710, 2024 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-39447808

RESUMEN

The aim of this study was to analyze the physicochemical properties of native Colombian Achira starch (Canna indica L.). Achira starch, with an amylose content of 49.07 % is classified as high amylose starch. Scanning electron microscopy (SEM) revealed grains with an average size of 54.34 µm in length and 34.93 µm in width, with spherical, ellipsoidal, and ovoid shapes. Mineral analysis identified phosphorus (P) and potassium (K) as the most important elements. For the first time, transmission electron microscopy (TEM) and X-ray diffraction (XRD) confirmed the presence of nanocrystals with a length of 23.95 nm, a width of 6.44 nm, and a hexagonal crystal structure (B-type starch). Thermogravimetric analysis (TGA) showed mass losses associated with water, lipids, and protein carbohydrates. Differential scanning calorimetry (DSC) showed gelatinization at 61.17 °C. The pasting profile indicated hydrogel behavior with a high peak viscosity of 13,690 cP due to the amylose content. The water absorption index (WAI) was 2.07 g/g, the water solubility index (WSI) was 3.04 g/g, and swelling power (SP) was 2.19 g/g. The presence of nanocrystals and the high amylose content indicate potential in the food industry.

7.
Nanomaterials (Basel) ; 13(17)2023 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-37686893

RESUMEN

The paper studies the changes in physicochemical properties of three types of hydroxyapatite (HAp): HAp-HB (from bovine sources), HAp-SC (chemically synthesized), and bioinspired HAp-SE (synthesized using eggshells) calcined under identical thermally controlled conditions from room temperature to 400, 500, 600, 650, 680, 700, 720, 750, 800, and 900 °C in furnace air. The thermogravimetric analysis (TGA) indicated distinct thermal transitions and coalescence phenomena at different temperatures for these samples due to their sources and mineral composition differences. Inductively coupled plasma (ICP) showed that HAp-H (human), HAp-HB (bovine), and HAp-SE (bioinspired) have similar Ca, P, and Mg contents. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that the coalescence phenomena increased in the crystallite size as the temperature increased. X-Ray diffraction (XRD) patterns revealed partial phase changes in the bioinspired sample (HAp-SE) and crystallite growth in all samples, resulting in full width at the half maximum (FWHM) and peak position alterations. Fourier-transform infrared spectroscopy (FTIR) showed that HAp-SE exhibited a partial phase change due to dehydroxylation and the presence of functional groups (PO43-, OH, and CO32-) with varying vibrational modes influenced by the obtained method and calcination temperature. Raman spectra of the HAp-SE samples exhibited fluorescence at 400 °C and revealed vibrational modes of surface P-O. It observed the bands of the internal phosphates of the crystal lattice and shifts in the band positions at higher temperatures indicated phosphorus interacting with carbon and oxygen, triggering dehydroxylation.

8.
Int J Biol Macromol ; 236: 123981, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36907301

RESUMEN

Maize grains are composed of the pericarp, endosperm, and germ. Consequently, any treatment, such as electromagnetic fields (EMF) must alter these components, which in turn alters the physicochemical properties of the grain. Since starch is a major component of corn grain, and given the great industrial importance of starch, this study investigates how EMF affects the physicochemical properties of starch. Mother seed were exposed to three different intensities 23, 70, and 118 µT for 15 days. Except for a slight porosity on the surface of the starch of the grains of plants exposed to higher EMF, the starch showed no morphological differences between the different treatments and the control (according to scanning electron microscopy). The X-ray patterns showed that the orthorhombic structure was kept constant, unaffected by the intensity of EMF. However, the pasting profile of starch was affected, and a decrease in the peak viscosity was obtained when the intensity of EMF increased. In contrast to the control plants, FTIR shows characteristic bands which can be attributed to the stretching of the CO bonds at wave number 1.711 cm-1. EMF can be considered a physical modification of starch.


Asunto(s)
Almidón , Zea mays , Almidón/química , Zea mays/química , Campos Electromagnéticos , Semillas/química , Endospermo
9.
Carbohydr Polym ; 281: 119048, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-35074120

RESUMEN

This work focused on studying the effect of lamellae presence on the pasting profile of isolated avocado starch (C-type) obtained by a combined mechanical and ultrasonic process. Inductively Couple Plasma indicates that this starch is rich in P, K, Na, and Ca. This starch exhibits the most crystalline structure reported so far. The correlation between the morphological and structural properties throughout its pasting profile explains its apparent viscosity behavior. Granules exhibit a non-conventional irregular morphology with sizes ranging from 35 to 40 µm in their long side. DSC reveals endothermal transitions at 68 °C and 119 °C associated with the nanocrystals solvation and amylose-lipid complex, respectively. After gelatinization, the presence of lamellae originated from the partial fragmentation of the crystals. The pasting end exhibited a combined behavior between custard and hydrogel. This correlation could be considered a new methodology to understand the pasting behaviors in any starch.


Asunto(s)
Persea , Almidón , Amilosa/química , Almidón/química , Temperatura , Viscosidad
10.
Int J Biol Macromol ; 183: 1723-1731, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-34051250

RESUMEN

This work focused on studying the mineral composition, morphology, thermal, structural, and pasting properties of isolated plantain starch. Plantain starch is rich in K, and other ions as Mg, Ca, P, and Si were found. This starch exhibits lenticular, elliptical, and semispherical morphologies. Two endothermal events present in the thermogram were identified as the hexagonal and orthorhombic solvation. C-type starch formed by hexagonal and orthorhombic nanocrystal was completely indexed. The ash content showed the presence of calcium phosphate (KCaP2O7), Calcium Magnesium Phosphate (Ca2.71Mg0.29(PO4)2), and silicon oxide (SiO2). The pasting profile of this starch behaves between a custard and a hydrogel. Scanning electron microscopy of the lyophilized samples along pasting profile confirms that the shear and van der Walls forces and slurry morphology govern the pasting profile changes.


Asunto(s)
Harina/análisis , Musa/química , Almidón/química , Rastreo Diferencial de Calorimetría , Microscopía Electrónica de Rastreo , Estructura Molecular , Resistencia al Corte , Difracción de Rayos X
11.
Int J Biol Macromol ; 177: 430-436, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33621570

RESUMEN

This work focused on the physicochemical properties of isolated Amaranth starch. Inductively coupled plasma (ICP) showed that amaranth is low-lipid calcium and magnesium source for the human diet. Scanning Electron Microscopy showed that isolated granules are in the range of sub and micro size. DSC starch thermogram showed a gelatinization temperature of 67.9 °C and an enthalpy of 10. 6 J/g suggesting the presence of an ordered crystalline structures. High-resolution X-ray diffraction showed the isolated starch contents nanocrystals with an orthorhombic crystalline structure whose pattern was indexed. The pasting profile showed that this kind of starch has an end cold viscosity as a custard, making it useful for infantile formulations. It does not present dynamic viscosity and would not be a problem when swallowed. A very important finding in this work was that the orthorhombic nanocrystals, after solvation during gelatinization, do not contribute to the apparent viscosity development.


Asunto(s)
Amaranthus/química , Almidón/química , Almidón/aislamiento & purificación
12.
Food Chem ; 360: 130035, 2021 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-34029922

RESUMEN

Instant controlled pressure drop (DIC) has been used as a pre-treatment to increase extractable polyphenols (EPP), mainly attributed to matrix structure expansion. This work aimed to evaluate the effect of DIC on non-extractable polyphenols (NEPP), EPP, and dietary fiber on grape pomace. At 0.2 MPa-60 s was observe an increase of total EPP and total anthocyanins. Despite the increment of EPP, was observe the lowest anthocyanins and non-extractable proanthocyanidins content at 0.4 MPa-120 s. This increase was due to a partial transformation of anthocyanins into phenolic acids and the depolymerization of proanthocyanidins. Also was observe partial solubilization of insoluble dietary fiber. Morphologically, the size of the pores generated by DIC was more significant at higher pressures. Thus, DIC modified the morphology and profile of the polyphenols of grape pomace, producing phenolic compounds of simpler structure and improving their antioxidant capacities.


Asunto(s)
Fibras de la Dieta/análisis , Polifenoles/análisis , Vitis/química , Antocianinas/análisis , Antioxidantes/química , Frutas/química , Fenoles/análisis , Extractos Vegetales/química , Proantocianidinas/análisis
13.
Lab Anim ; 55(1): 30-42, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32460606

RESUMEN

Changes in bone mineral content of calcium (Ca), phosphorous (P), magnesium and potassium for male and female Wistar rats during their development from 3 weeks old to adulthood (27 weeks old) were measured. Bone mineral content was related to areal bone mineral density (BMD) which was measured in vivo at the femoral neck using a calibrated X-ray transmission system to obtain basal curves as a function of the age of the specimen. Diagnostic curves were built to determine low BMD (osteopaenia) and osteoporosis in female rats fed a Ca-depleted diet (50%) based on the obtained data and the criteria established by the World Health Organization. Bone mineral content is directly related to sex and age, but P did not change throughout the experimental period. P content did not exhibit significant changes with growing, while Ca was greatest in male rats, producing significant differences in the Ca:P ratio. Male rats reach the Ca:P ratio peak before female rats. However, areal BMD does not follow the same trend. On the other hand, osteoporosis produced a 45% decrease in this parameter for young and mature adults. These results make Z-score values available to diagnose bone-mass losses and hence the possibility of improving the conditions of non-contact measurement of BMD in vivo. This technique can be used for future experiments with Wistar rats.


Asunto(s)
Densidad Ósea , Fémur/fisiología , Osteoporosis/fisiopatología , Ratas/fisiología , Animales , Modelos Animales de Enfermedad , Femenino , Masculino , Ratas Wistar
14.
Biol Trace Elem Res ; 194(1): 168-176, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31127473

RESUMEN

This work determines the effect nopal consumption at different maturity stages (60, 200, 400, and 600 g) as the only calcium source in bone metabolism. The apparent mineral absorption, the biomarkers of bone metabolism, the bone mineral density at different femoral regions, and crystal properties of the bone were evaluated during the growth stage. The Ca absorption was increased with the rat age in most of the experimental groups, while Mg supplementation decreased intestinal absorption probably due to a saturation process. Intestinal Ca and Mg absorption showed an opposite trend; this result suggests that both ions can compete for vitamin D absorption sites. The percentage of absorption of K was lower in the groups fed with Nopal; nevertheless, due to supplementation, the net absorption was higher than the control group. In all groups, osteocalcin levels decreased with the rat age. Nopal consumption increased osteocalcin levels during the adolescence stage in comparison to the control group. Amino N-terminal propeptide of type I procollagen levels increased in puberty and adolescence in all groups compared to the control group. Bone mineral density in different femoral regions was lower in the groups fed with nopal at early maturity stages (N-60 and N-200) than the groups fed with nopal at late maturity stages (N-400 and N-600). The crystal size of hydroxyapatite exhibited changes for all the groups, indicating the inclusion of mono and divalent ions in calcium replacement. On this basis, the nopal at late maturity stage contributed to bone formation.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Huesos/efectos de los fármacos , Huesos/metabolismo , Calcio/metabolismo , Minerales/metabolismo , Opuntia/química , Proteínas de Vegetales Comestibles/farmacología , Animales , Biomarcadores/análisis , Biomarcadores/metabolismo , Calcio/análisis , Crecimiento/efectos de los fármacos , Crecimiento/fisiología , Masculino , Minerales/análisis , Ratas , Ratas Wistar
15.
Biol Trace Elem Res ; 197(1): 224-232, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31919787

RESUMEN

This study evaluates the effect of three calcium levels in the diet (normal, moderate, and severe calcium depletion) on bone metabolism of male Wistar rats during their growth period. Bone mineral density (BMD) and femur length were determined in vivo during the growth stage using a single X-ray transmission system. The apparent calcium absorption was calculated in the rat adolescent and adulthood stages. At the end of the experiment, calcium concentrations in serum and urine were analyzed. The bones were evaluated postmortem to corroborate in vivo analyses. Microstructural properties of cortical and trabecular tissues of femurs bones were assessed using scanning electron microscopy. Bone mineral contents (Mg, Ca, P, and K) were quantified by inductively coupled plasma. Severe calcium depletion in the diets in the development stage affects the bone quality parameters such as bone mineral density and mineral content. Moreover, it was found thinner cortical and trabecular bone areas. Additionally, it was found that severe calcium depletion increased the apparent absorption of calcium as a defense mechanism, but with the decrease of the BMD peak, and the thickness of cortical bone as well as trabecular bone porosity. The severe calcium depletion increased the efficiency of apparent absorption calcium as a defense mechanism, but, even so, decreases the BMD peak as well as the thickness of cortical bone and trabecular bone porosity.


Asunto(s)
Calcio , Magnesio , Animales , Densidad Ósea , Dieta , Fémur , Masculino , Ratas , Ratas Wistar
16.
Carbohydr Polym ; 246: 116555, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32747238

RESUMEN

Functional modifications of starch, such as paste properties, retrogradation, water absorption indexes, solubility, and swelling capacity, are induced by the amylose-lipid complex. This research comprehends the study of functional properties of extruded maize starch mixed with fatty acids (stearic acid, oleic acid, and maize oil) and the formation of amylose-lipid complexes. Maize starch with lipids (5 or 10 %), moisture (35 %) was extruded (single screw). Starch granule was modified by extrusion, to a lesser extent at 10 % of lipids, especially stearic acid, which covers starch granule surface. Viscosity decreased meaningfully with stearic acid addition. DSC showed both starch gelatinization enthalpy and amylose-lipid complex enthalpy for stearic or oleic acid, but it was just the first enthalpy for maize oil. X-ray diffraction showed orthorhombic crystals with or without the presence of lipids. Our results indicated that stearic acid yielded the highest amount of amylose-lipid complexes.


Asunto(s)
Amilosa/química , Lípidos/química , Ácido Oléico/química , Extractos Vegetales/química , Ácidos Esteáricos/química , Zea mays/química , Rastreo Diferencial de Calorimetría , Cristalización , Calor , Solubilidad , Viscosidad , Agua/química , Difracción de Rayos X
17.
Food Chem ; 315: 126241, 2020 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-32014667

RESUMEN

Chemical modification with octenyl succinic anhydride (OSA) helps to control the physicochemical and thermal properties of isolated starches. The main objective, herein, was to partially characterize modified starches from Dominico-Harton plantain and FHIA 21 planted in Colombia. The highest degree of substitution was found in FHIA 21 (0.020) starch with 3% OSA and 4-h reaction at room temperature. The grain morphology was not affected, but small changes on the surface were evident. Both modified starches reported absorption bands in the IR at 1566 and 1738 cm-1, proper for these types of starch derivatives. The hexagonal and monoclinic structures of starch were altered through chemical modification. In the bending curves, a drastic decrease in the viscosity of the modified starches was observed with respect to the native one. The gelatinization temperatures of the modified starches were similar to those of the isolated starches.


Asunto(s)
Plantago/química , Almidón/química , Amilosa/análisis , Colombia , Microscopía Electrónica de Rastreo , Plantago/crecimiento & desarrollo , Almidón/análogos & derivados , Anhídridos Succínicos/química , Viscosidad , Difracción de Rayos X
18.
Food Chem ; 298: 124982, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31261014

RESUMEN

This work studies the physicochemical properties of quinoa flour and isolated starch. Starch in the seed forms clusters rich in amylopectin that are immersed in a matrix with spherical and polygonal shapes in the submicron scale. The isolated quinoa starch is rich in Sulphur and Magnesium. The quinoa flour has a higher content of protein, carbohydrates and lipids than isolated starch. Water absorption and water solubilized indexes of starch exhibited high values that could had originated by the extraction method. The broad peaks found for the X-ray patterns of isolated quinoa starch indicate that amylose and amylopectin are composed by nanocrystals, according to the PDF-4+2019 software. The viscosity of isolated starch had a higher value than flour; therefore, the quinoa starch could be used as a thickener in different formulations with the advantage of keeping a significant presence of minerals which are important to the human health.


Asunto(s)
Chenopodium quinoa/química , Harina/análisis , Análisis de los Alimentos/métodos , Almidón/química , Amilopectina/química , Amilosa/análisis , Microscopía Electrónica de Rastreo , Minerales/análisis , Semillas/química , Semillas/ultraestructura , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/análisis , Almidón/ultraestructura , Temperatura , Viscosidad , Agua/química , Difracción de Rayos X
19.
Food Chem ; 283: 83-91, 2019 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-30722929

RESUMEN

This work focused in the study of the changes on the physicochemical properties of isolated jícama starch (IJS), and IJS added with 0.15, 0.20, 0.30% Ca(OH)2 w/w. including: the structural, morphological, chemical, vibrational, pasting, rheological, and thermal characteristics. K, Ca, Na, and P were found in IJS. X-ray patterns, which showed that nanocrystals form the IJS according to the PDF-4 simulation. The functional properties were affected by the Ca inclusion, which originated electrostatic interactions. The gelatinization temperatures shifted to high values and exhibited an unfolding. The calculation of the IR absorption coefficient (ß) of the gelatinized samples as a function of the Ca2+ for the C-OH showed that the Van der Waals interaction causes the changes in the rheological-mechanical properties. The SEM images demonstrated that starch without alkali exhibited a porous network structure, while the starch with lime exhibited flakes and porous network. The gels of Jicama starch with Ca(OH)2 showed a viscoelastic behavior (G' > G″) with a reduction of their elastic module.


Asunto(s)
Hidróxido de Calcio/química , Pachyrhizus/metabolismo , Almidón/química , Amilosa/metabolismo , Microscopía Electrónica de Rastreo , Nanopartículas/química , Reología , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Temperatura , Viscosidad , Difracción de Rayos X
20.
Sci Rep ; 9(1): 5915, 2019 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-30976023

RESUMEN

This paper focuses on the study of the effect of the change of the crystal size on the shape and width of the X-ray diffraction patterns for defatted and deproteinized bones as well as incinerated biogenic hydroxyapatite obtained from bovine, porcine, and human bones. Inductively Couple Plasma showed the presence of some ions such as Mg, K, Al, Fe, Zn, and Na for all samples. The nanometric size of the crystals was determined through High Resolution Transmission Electron Microscopy in which ordered crystals were found. The calcination of raw clean bones at 720 °C produced a transition of crystal size from nano to micro due to a coalescence phenomenon, this was accompanied by a decrease of the peak width of the X-ray diffraction patterns due to the decrease of the inelastic scattering contribution from the microcrystals. A simulation of the effect of the crystallite size on the shape and width of the X-ray patterns was done using PDF-4 software which confirmed that raw ordered bone crystals produce broad peaks which so far have been erroneously assigned to polycrystalline hydroxyapatite with low crystalline quality.


Asunto(s)
Huesos/química , Durapatita/química , Animales , Bovinos , Cristalización , Humanos , Porcinos , Difracción de Rayos X
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