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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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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.

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