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The rational use of autoclaved starches in food applications is difficult because there is a lack of information on their structure-functionality relationship. The novelty of this research relies on disclosing such an association. Hylon V starch was autoclaved at 105, 120, and 135°C to investigate its crystalline and double-helical features and its relationship with functionality. In autoclaved Hylon V starch, interactions of amylopectin and amylose improved while the crystalline regions decreased. The degree of double helices (DD) decreased after autoclaving at 105°C and the degree of order (DO) increased after treatment at 120 and 135°C. The water solubility index (WSI) (4.63-6.38%) and swelling power (SP) (4.39-7.1 g/g) increased when the temperature increased. On the other hand, water (103.49-225.01%) and oil (61.91-94.53%) holding capacity (WHC and OHC, respectively) increased after autoclaving treatment, although the values decreased with the treatment intensity. The functional properties were affected when the structure changed as a function of the treatment temperatures. PCA analysis showed that WSI and SP of autoclaved Hylon V starch were associated with a high DD, with better compaction, and with stronger amylopectin-amylose interactions. WHC and OHC were associated with better crystallinity, stronger interactions of amylopectin and amylose, and heterogeneous double-helical crystallites. These findings are useful for understanding the structure-functionality relationship of autoclaved Hylon V starch and pave the way for future research regarding the effects of its incorporation on the properties of food matrices such as bread, yogurt, cakes, and pudding.

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Resumen: Los productos acuáticos reestructurados se procesan principalmente a partir de especies de pescado infravaloradas, recortes de filetes o subproductos de especies de pescado no comerciales. Una de las pesquerías subvaloradas en el sur de México, es la del macabil (Albula vulpes). El objetivo de este estudio fue evaluar el efecto de la adición de harinas no convencionales y la reducción del nivel de cloruro de sodio en las propiedades mecánicas y funcionales de productos reestructurados de macabil. Se elaboraron reestructurados de macabil para analizar las muestras con harina de amaranto (HA) o harina de grillo (HG) doméstico (0 %, 5 % y 10 %) y tres niveles de sal (0 %, 1 % y 2 %). Se evaluó la pérdida de agua por cocción, la cantidad de agua extraíble y la textura de los geles. El uso de ambas harinas no convencionales disminuyó la pérdida de agua por cocción entre un 49.09 % y 61.97 %, con 1 % de sal. La adición de sal redujo el agua extraíble del reestructurado. Los valores de dureza variaron (P < 0.05) entre tratamientos. La mayor dureza se obtuvo en los tratamientos con HA al 10 % y sal al 1 % (64.55 N) y con HG al 10 % y sal al 2 % (63.50 N). La cohesividad varió de 0.53 a 0.71 (adimensional) en los tratamientos con 1 % y 2 % de sal, indicando pocos cambios en la estructura interna por efecto de los aditivos. Las harinas no convencionales permitieron la gelificación proteica, formando reestructurados con propiedades texturales adecuadas para un producto cárnico. La adición del 10 % de HG común o de HA y 1 % de uso de sal, en la formulación de reestructurados de pescado, ofrece una alternativa saludable en el desarrollo de alimentos de pescado.

Abstract: Restructured seafood products are primarily processed from undervalued fish species, fillet trimmings, or byproducts of non-commercial fish species. One of the underrated fisheries in southern Mexico is that of the bonefish (Albula vulpes). The objective of this study was to evaluate the effect of adding non-conventional flours and reducing the sodium chloride level on the mechanical and functional properties of restructured bonefish products. Bonefish restructured products were prepared to analyze samples with (0 %, 5 %, and 10 %) amaranth flour (AF) or cricket flour (CF) and three levels of salt (0 %, 1 % and 2 %). The cooking water loss, the amount of extractable water and the texture from gels were evaluated. The use of both non-conventional flours reduced cooking water loss by 49.09 % to 61.97 % with 1 % salt. The addition of salt reduced the extractable water in the restructured product. Hardness values varied (P < 0.05) among treatments. The highest hardness was obtained in treatments with 10 % AF and 1 % salt (64.55 N) and with 10 % CF and 2 % salt (63.50 N). Cohesiveness ranged from 0.53 to 0.71 (dimensionless) in treatments with 1 % and 2 % salt, indicating minimal changes in internal structure due to additives. Non-conventional flours allowed for protein gelation, forming restructured products with suitable textural properties for a meat product. The addition of 10 % CF or AF and 1 % salt in fish restructured product formulation offers a healthy alternative in the development of fish-based foods.

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Resumen Después de varias décadas, el Programa de Ciencias Médicas, Odontológicas y de la Salud sigue formando investigadores que integran las diversas instituciones en donde labora personal de salud. Es notable cómo algunos campos han crecido y cómo se ha incrementado la participación de las mujeres, tanto en maestría como en doctorado. Se presenta un panorama general de ingreso y graduación de acuerdo con los campos de conocimiento y por el sexo de las personas. Se hace un comentario sobre los cambios en las personas que dirigen instituciones que, en algunos casos, por más de 100 años eran dirigidas por personas del sexo masculino.

Abstract By reviewing the scientific literature specialized in sleep disorders (TS) carried out in Mexico, especially at the TS Clinic (Faculty of Medicine-UNAM) at the General Hospital of Mexico (CTS-HGM) from 1948 to 2020, it was possible to document the history of ST research in Mexico and the role played by the CTS-HGM. Sleep Medicine (MS) is one of the newest specialties in Mexico and case research in this field began around 1948, while formal research in 1974. The founding of CTS-HGM in 1997 led to significant development in TS research in Mexico. In addition, the CTS-HGM became a center of care for patients with these problems, as well as important research center since its publications cover all the diagnostic categories of the CITS.

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This research investigated the impact of ohmic heating (OH) on the physicochemical properties and resistant starch formation in native corn starch. Electric field strengths (EFS) of 50, 75, and 100 V/cm were applied to native starch, at a starch-water ratio of 1:1 w/v. The conductivity of the medium is a crucial factor in ohmic heating. In this study, the conductivity values at 120 °C were measured at 1.5 mS/m. The study revealed two distinct outcomes resulting from the application of different EFS. Firstly, a thermal effect induced gelatinization, resulting in a reduction in the enthalpy of corn starch, an increase in the water absorption index (WAI) and the water solubility index (WSI), and a decrease in peak viscosity. Secondly, a non-thermal effect of OH was observed, leading to the electrolysis of certain starch compounds and water. This electrolysis process generated radicals (-OH) that interacted with starch components, augmenting the percentage of resistant starch. This increase was associated with elevated levels of carbonyl and carboxyl groups at 75 and 100 V/cm.

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The development of bio-based materials remains one of the most important alternatives to plastic materials. Although research in this field is growing, reporting various materials and methodologies, it is still necessary to increase exploration. The aim of this work was to expand and complement previous research on the preparation and characterization of high- and low-methoxyl pectin films obtained by casting, with the addition of commercial and recovered sunflower waxes. The results showed that the addition of sunflower waxes to the pectin matrix generated some discontinuity in the aggregate, increasing the thickness and roughness of the film. However, due to their hydrophobic nature, the waxes contributed to lower vapor transmission rate values of the films. On the other hand, the low-methoxyl pectin films had a more crystalline structure, which could help to diminish water vapor permeability values, mechanical resistance and rigidity, and improve their elongation. Regarding chemical characteristics, most of the raw materials' chemical groups were found in the resulting films, and the presence of C-H bending due to pectin gelation was observed. Finally, the compatibility and contribution of pectin and sunflower waxes to the production of the films were demonstrated, as well as the possibility of using materials from industrial waste in food packaging applications.

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The nixtamalization process used for tortilla production entails extended processing time and generates pollutant effluents. Ohmic heating (OH) is an emerging technology that uses an alternating electric current for rapid and uniform food heating and mitigates effluent concerns. However, gaps exist in nutrient bioavailability studies. In this work, we assessed OH's impact on tortilla nutritional value, protein, and calcium using a rat model. Twenty-five male Wistar rats were fed one of four diets for 21 days: raw corn (RC) as an experimental control, OH-processed tortillas (OHTs), traditionally processed tortillas (TPTs), commercial tortillas (CTs), and a casein diet (CD) as a growth control. Despite similar protein and macronutrient profiles, OH significantly enhanced insoluble fiber content. The weight gain sequence was OHTs > TPTs > CTs > RC. OHTs exhibited superior protein digestibility (88.52%), which was 3% higher than other diets. The serum albumin (2.63-2.73 g/dL) indicated moderate malnutrition due to the tortilla's lower protein content. Nonetheless, the protein efficiency ratio (1.2-1.74) showed no significant difference from TPTs. Bone characteristics and fracture strength resembled the tortilla-fed groups, surpassing RC. X-ray diffraction and scanning electron microscopy confirmed that the OHT and TPT diets improved male rat bone thickness and crystallinity. The findings suggest the potential for OH as an eco-friendly tortilla production method, maintaining nutritional value comparable to traditional methods.

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Sorghum is the fifth most harvested crop worldwide, being the popped sorghum as one of the most common snacks in India and some Asian regions. Therefore, this study evaluated how the processing method influences the microstructure, volumetric and textural properties of popped sorghum microstructure, volumetric and textural properties. White sorghum "Paloma" variety (11% moisture) was assessed, which was popped using three processing methods: microwave, pan-frying, and hot salt-frying using three temperature levels. Volumetric and yield characteristics were evaluated for the popped kernels, as their microstructure and texture profile. The popped sorghum obtained through the hot salt-frying method had a microstructure composed of polygonal cells. Also, it showed the best volumetric characteristics (volume), good expansion index, and high process yield. Finally, the hot salt-frying method showed better textural features associated with the attributes of a satisfactory product for consumers.

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Valorization of by-products obtained from food processing has achieved an important environmental impact. In this research, sunflower wax recovered from oil refining process was incorporated to low and high-methoxyl pectin films produced by electrospraying. Film-forming solutions and wax-added electrosprayed films were physical and structurally evaluated. The addition of sunflower wax to the film-forming solutions reduces conductivity while raising surface tension and density, whereas the type of pectin had a larger impact on viscosity, with the low-methoxyl solution having the highest value. These changes in physical solution properties influenced the film characteristics, observing thicker films with lower water vapor transmission rate (WVTR) when adding wax. Micrographs obtained by scanning electron microscopy (SEM) revealed the presence of wax particles as small spherical shapes, having a good distribution through the sectional area of films. According to X-ray diffraction (XRD), atomic force microscopy (AFM) and mechanical properties analyses, the presence of wax had an impact on the degree of crystallinity, producing a more amorphous and rougher film's structure, without affecting the elongation percentage and the tensile stress (p>0.05). These results showed that wax addition improves the physical properties of films, while the suitability of using both pectins and the electrospraying technique was demonstrated.

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Biological, physicochemical, structural, and thermal properties of PVA-based electrospun wound dressings added with hydrolyzed collagen (HC) and different concentrations of Hypericum perforatum ethanolic extract (EEHP) were studied. Membrane characterization was carried out by X-ray diffraction, Fourier infrared spectroscopy, differential scanning calorimetry, barrier properties, scanning electron microscopy, image analysis (diameter and pore size), as well as antimicrobial and anti-inflammatory activities. Results showed that the PVA/HC/EEHP materials, fabricated under controlled conditions of temperature and humidity, generated fiber membranes with diameters between 140−390 nm, adequate porosity and pore size for cell growth (67−90% and 4−16 µm, respectively), and good barrier properties (0.005−0.032 g·m−2 s−1) to be used in the treatment of conditions on the skin, and was even better than some commercial products. Finally, they showed to have anti-inflammatory (>80%), and antimicrobial activity against S. aureus and S. epiderm. Furthermore, higher crystalline structure was observed according to the EEHP concentration. In addition, this is the first report in which PVA/HC/EEHP membranes are successfully fabricated and characterized.

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The aim of this study was to evaluate the effect of acid hydrolysis and succination upon single and a combination of both of them as a dual modification on the morphological, structural, thermal, and pasting profile of the achira starch in order to expand its potential food applications. The surface of achira starch granules was eroded with acid hydrolysis, while the succination resulted in the formation of pores or cavities, having a slight impact on the crystallinity and the gelatinization enthalpy. Succinated starch presented the lowest transition temperatures (To = 60.29 °C, Tp = 65.03 °C and Te = 69.86 °C) compared to other starches in this study. The succination increased the final viscosity (3808 cp) when compared with the native starch (3114 cp), while acid hydrolysis resulted in a decreased value (735 cp). These are desirable properties for its possible use as an additive in bakery industry processes.

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Normal and high amylose corn starches were modified using HMDSO plasma at different time treatments. Changes in functional properties of starch granule, film-forming solutions (FFS) and films were investigated. SEM analysis revealed HMDSO coating deposition on the granule surface, which limited the amylopectin leach out from the granules to the continuous matrix, affecting the rheological properties of the FFS. The amylopectin restriction resulted in a low reinforcement of the network decreasing the viscosity as indicated by n and k values. Also, a gel-like behavior (G' > G″) was observed when the amylose and time treatment increased, suggesting that the matrix becomes less elastic with softer entanglement. This behavior was confirmed by creep test and Burger model parameters. The plasma treatments allowed obtaining FFS with low viscosity, suitable for developing soft and hydrophobic films with low flexibility, as indicated by the decrease of the maximum stress, Hencky strain and permeance values.

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In this study, the resistant starch (RS) formation, crystallinity, and double helical order of autoclaved (120 °C) normal (ANS) and high amylose (AHS) corn starches retrograded at ~4-26% of water content were investigated. ANS and AHS retrograded at ~25-26% of water content were more crystalline (~35-40%) and formed by more close-packed double helices (R1000/1022 cm-1 = 1.145-1.290). The highest content of RS (38.8%) was found in AHS retrograded at 25.52% of water content meanwhile in ANS, the maximum content of RS was 6.6% at 21.60% of water content despite its structural order was increased with the increase of water content. The recrystallization of amylopectin interfered with the formation of homogeneous crystalline structures of amylose preventing the formation of retrograded RS in ANS, while in AHS, a relationship between structure and RS formation was observed, suggesting that the close-packed double helices and the proportion of homogeneous amylose crystallites increased the resistance to enzymatic digestion.

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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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Two maize starches (Normal and Hylon VII) were hydrolyzed using HCL for 15 days at room temperature. The water holding capacity -WHC and oil holding capacity- OHC were evaluated to describe the changes during the reorganization of hydrolyzed material. The structure was assessed using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR). A hydrolysis degree of 20% was reached with a complete granular structure disruption. During acid hydrolysis, the rearrangement of decoupled double helices favored the order degree. The hydrolysis of the amorphous region decreased the enthalpy of gelatinization. This effect was more noticeable in the normal starch. The changes promoted during the hydrolysis favored the reorganization of the network resulting in high values in WHC and OHC for both starches. The acid-treated starches obtained could be used as fillers, employing these materials with induced crystalline regions.

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Acrylamide can be generated from food components during tortilla chips frying. Thus, the aim of this research was to study different nixtamalization processes as traditional (TNP) with lime [Ca(OH)2], ecological (ENP) with CaCO3, classic nixtamalization (CNP) that uses wood ash and extrusion (EXT) with no Ca+2 source on mitigating the acrylamide formation in deep-fat frying tortilla chips. Acrylamide quantification was done through HPLC-UV. Lower acrylamide content in tortilla chips was for CNP with 46.3 µg/kg, followed by TNP with 55.0 µg/kg, ENP with 694.6 µg/kg and EXP with 1443.4 µg/kg. Differences in acrylamide values among samples can be related to effect of cations (Ca2+, Mg2+, Fe2+, Zn2+, Na+ and K+) present in wood ashes, lime and salts used as raw materials. Correlation of (r = 0.85; p <0.0005) was observed in color of tortilla chips, moisture, texture, blisters, and oil with acrylamide. Nixtamalization process is an effective and inexpensive strategy for acrylamide mitigation.

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In this study, the effect of amylose content and cold plasma treatment on starch films properties was investigated. Films from normal (30%) and high amylose (50 and 70%) starches were subjected to hexamethyldisiloxane (HMDSO) cold plasma treatment. Morphological, structural, mechanical and barrier properties of the films were evaluated. The amount of remnant starch granules (RSG) in the films depended on the amylose content and on the gelatinization extent of the starch. This behavior was corroborated on the films from starch with 50% amylose, where the loss of RSG resulted in poor barrier properties and high hydrophilicity. Moreover, HMDSO cold plasma treatment incorporated methyl groups improving the hydrophobic properties and favored the helix ordering of the starch components resulting in a limited water-film interaction. Furthermore, the simultaneous effect of HMDSO coating and the ordering of the structures reinforced the surface of the films, improving the mechanical properties.

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We studied the changes in the phytochemicals profile of two instant corn flours produced by different process: traditional nixtamalization process (TN) and by ohmic heating process (OH). The highest total phenolics content was found in the OH flours (OHF), which showed predominance of bound phenolics and free flavonoids compared with the TN flours (TNF). Ferulic acid measured by HPLC-DAD was the most abundant compound in its bound form in the OHF, but decreased by 57% in TNF. The insoluble fiber content was preserved by the OHF (17.49%) and the soluble fiber increased ∼65% compared with TNF. These data suggest that instant corn flours processed by OH preserves the phenolic profile and antioxidant profile similarly than flours processed by TN; furthermore, water waste was reduced significantly, and no effluents were produced in the ohmic heating process.

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Functional confectionery can be exploited as a vehicle for the protection of phenolic compounds (PCs) and for enhancing absorption during the gastrointestinal (GI) process. In this study, a confection containing 20% of mango bagasse (MB), gelatin and pectin was formulated. The PC profile, antioxidant capacity, in vitro bioaccessibility and apparent permeability (Papp) during mouth-stomach-intestine digestion (15, 30, 60, 120 min) and in vitro colonic fermentation (6, 12, 24 h) were evaluated for MB and the mango bagasse confection (MBC). HPLC-DAD analysis showed that mangiferin (830.69 µg g-1) was the most abundant compound in MBC. Total PCs (4.14 mg g-1), quercetin (244.83 µg g-1), and gallic acid (GA) (285.43 µg g-1) were highly bioaccessible mainly at the intestine at 60-120 min of digestion. GA was the most bioaccessible compound. Total flavonoids (TFs) and condensed tannins (CTs) had the maximum bioaccessibility in the mouth and stomach, respectively. For the permeability studies, PCs showed efflux rather than uptake in the intestine. Those compounds that exhibited intestinal absorption were mangiferin > GA > total PCs > TFs, whereas quercetin and CT absorption was negligible. The antioxidant capacity remained unchanged along the GI, mangiferin and quercetin being the most likely compounds to exert this activity. Overall results indicate that MBC has higher bioaccessibility, absorption and antioxidant capacity than MB, suggesting an effective protective role of gelatin and pectin, giving insight into the potential of MBC as a functional food.

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The quality of extruded snacks can be affected not only by processing conditions, but also by some factors like the concentration and type of ingredients incorporated in their formulation and the working conditions used. Although the process conditions have been established with measurable textural properties, sensory qualities have not been correlated with these responses in expanded extruded snacks made with added functional ingredients. Therefore, in this study the effect of adding textured soy flour (TSF) and whole wheat flour (WWF) to refined wheat flour in the production of extruded snacks and expanded with hot air was evaluated. A response surface design using two levels with five central points was applied to obtain the best combinations of functional ingredients added, holding the parameters of the extrusion process and moisture of treatments. Some texture characteristics and sensory analysis were used as response variables, such as, hardness, fracturability, toughness, crispness, granularity, and chewiness. Likewise, the rate of expansion was evaluated. The results showed that the level of substitution of WWF, especially levels of 15%, had a significant effect on the hardness perceived by the panelist during sensory evaluation. The TSF at concentrations of ≥15%, favored the fracturability and crispness of the samples. It was found that the best expansion index was with the combination of 5% TSF and 15% WWF. Although a correlation between instrumental and sensory tests carried out on the extruded snacks expanded was not found. PRACTICAL APPLICATIONS: The physical characteristics of the extruded snacks such as expansion, hardness, and density are important parameters in terms of consumer acceptability of the final product as well as their functional properties. In other words, the appearance and texture are two of the most important attributes that can be seen in snack foods. In particular, the texture can be measured by intrinsic tests: objective (instrumental) and subjective (sensory). That is because the instrumental analysis provides parameters such as firmness, brittleness, consistency, chewiness, among others, when subjected to different stress, strain, and strain rates at the snacks. Similarly, sensory analysis, allows us to see features that include mechanical attributes (concerning the reaction to the applied force), geometric attributes (concerning the shape, size, and orientation of the particles within the food), and attributes related to the perception of moisture or fat content.

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Approximately 80% of sorghum phenolic compounds are linked to arabinoxylans by ester bonds, which are capable of resisting the digestion process in the upper gastrointestinal tract, compromising their bioaccessibility and biological potential. The aim of this study was to evaluate the effect of the extrusion process on the content of phenolic compounds in sorghum bran and its impact on phenolic compounds and antiradical and anti-inflammatory capacity. Results revealed that the extrusion process increased total phenol content in sorghum bran compared to nonextruded sorghum, particularly for extrusion at 180°C with 20% moisture content (2.0222 ± 0.0157 versus 3.0729 ± 0.0187 mg GAE/g +52%), which positively affected antiradical capacity measured by the DPPH and TEAC assays. The percentage of inhibition of nitric oxide (NO) production by RAW cells due to the presence of extruded sorghum bran extract was significantly higher than that of nonextruded sorghum bran extract (90.2 ± 1.9% versus 76.2 ± 1.3%). The results suggest that extruded sorghum bran could be used as a functional ingredient and provide advantages to consumers by reducing diseases related to oxidative stress and inflammation.