36,194 research outputs found
Emprego da tecnologia supercrítica para a valorização do resíduo de semente de chia (Salvia hispanica)
Full text linkDissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia de Alimentos, Florianópolis, 2014.A chia (Salvia hispanica) é uma planta cultivada nas Américas do Sul e Central, cuja semente é fonte de antioxidantes naturais e ácidos graxos essenciais. O presente estudo avaliou a obtenção de extratos de torta de chia, subproduto proveniente da extração do óleo de chia. Foram aplicadas as técnicas a baixa pressão como extração em Soxhlet (SOX), ultrassom (US) e maceração (MAC) utilizando etanol (EtOH), hexano (Hex) e acetato de etila (EtOAc) como solventes, a fim de comparar com o processo de extração supercrítica (ESC). As operações de ESC foram realizadas com pressões de 150 bar a 300 bar e temperaturas de 40 °C e 50 °C empregando o CO2 como solvente. Também foi realizada a aplicação de EtOH e EtOAc como cossolventes no processo de ESC em concentrações de 2,5 até 7,5 %. O processo de extração supercrítica sequencial (ESC-S) foi estudado, o qual possui duas etapas de extração, com uma despressurização rápida do sistema entre a primeira e a segunda etapa. A construção da curva cinética e modelagem matemática de processos de ESC e ESC-S foram executadas, além da estimativa de custos de manufatura da instalação de uma unidade industrial de ESC. Todos os extratos obtidos foram submetidos a análises de atividade antioxidante (método ABTS), teor de fenólicos totais (TFT), perfil de ácidos graxos e atividade antimicrobiana. Nas extrações a baixa pressão, os maiores rendimentos foram obtidos utilizando SOX com EtOH (15,4 ± 0,4 %). Nas ESC com CO2 puro, a pressão de 300 bar permitiu alcançar rendimentos de até 10,6 ± 0,2 %, na maior temperatura estudada. A utilização de cossolvente causou aumento no rendimento de extração (11,3 ± 0,1% utilizando EtOH a 7,5%). Os extratos obtidos em extrações a baixa pressão com EtOH e EtOAc obtiveram os melhores valores de TFT e atividade antioxidante. A utilização de cossolvente afetou positivamente os resultados de TFT e atividade antioxidante dos extratos de ESC. O perfil de ácidos graxos dos extratos confirmou altos teores de ácido linoleico e a-linolênico em todos os extratos testados. Extratos obtidos pelas diferentes técnicas mostraram atividade antimicrobiana contra B. cereus. A ESC-S com despressurização rápida teve efeito positivo com relação ao rendimento, onde foi atingido rendimento de 8,7 ± 0,2%, estatisticamente igual ao rendimento obtido em ESC na mesma condição, porém reduzindo o tempo de extração pela metade. A realização da segunda etapa de ESC-S utilizando EtOH 7,5% ocasionou um aumento no TFT dos extratos obtidos. O modelo que melhor se ajustou as curvas experimentais foi o modelo de Martínez et al. (2003). Segundo o modelo de Sovová (1994), para os processos de ESC e primeira etapa de ESC-S, o mecanismo de convecção foi mais representativo. Na segunda etapa de ESC-S o mecanismo de difusão também mostrou representatividade. A ESC-S quando realizada até a etapa de despressurização (ESC-Desp) mostrou ser um processo economicamente viável e lucrativo para aplicação em escala industrial, com valores de extrato competitivos com os valores de mercado, gerando extratos de alta qualidade em um menor tempo de processo.Abstract : Chia (Salvia hispanica) is a plant cultivated in South and Central America, whose the seed is a source of natural antioxidants and essential fatty acids. The present study evaluated the extracts attainment from chia seed cake, which is a byproduct from chia seed oil extraction process. It were applied low-pressure techniques, like Soxhlet extraction (SOX), ultrasound assisted extraction (US) and maceration (MAC) using ethanol (EtOH), hexane (Hex) and ethyl acetate (EtOAc) and as solvents with the objective of comparing with the high pressure process, performed by supercritical fluid extraction (SFE). SFE were performed at pressures from 150 to 300 bar and temperatures of 40 °C and 50 °C, using CO2 as solvent. It was also performed an application of EtOH and EtOAc as cosolvents on SFE process, using concentrations from 2.5 to 7.5%. A sequential supercritical fluid extraction (S-SFE) process was studied, wich includes two steps of extraction, with a fast depressurization of the system between the first and the second step of extraction. The kinetic extraction curves of SFE and S-SFE processes were built and mathematical models adjusted the experimental data. It were also performed an estimative of manufacturing costs from installing a supercritical fluid extraction industrial unit. All extracts was submitted to antioxidant analysis (ABTS method), total phenolics content (TPC), fatty acids profile and antimicrobial analysis. Among low-pressure extraction, the highest yield was achieved using SOX with EtOH (15.4 ± 0.4 %). Among the SFE assays using pure CO2, the pressure of 300 bar allowed to achieve yields up to 10.6 ± 0.2 %, in the highest tested temperature. The use of a cosolvent caused increase in yield (11.3 ± 0.1% using EtOH 7,5%). Extracts obtained by lowpressure techniques using EtOH and EtOAc showed the best values of TPC and antioxidant activity. The using of a cosolvent affected in a positive way the results of TPC and antioxidant activity of SFE extracts. The fatty acids profile of the extracts confirmed the high content of linoleic and a-linolenic acids in all tested extracts. Extracts obtained by different techniques showed antimicrobial activity against B. cereus. SSFE process with fast depressurization caused a positive effect in yield, achieving a yield of 8.7 ± 0.2%, statiscally equal to the yield obtained by SFE using the same condition, but reducing the extraction time by half. The performance of the S-SFE second step using EtOH 7.5% caused an increase in the TPC of the obtained extracts. Martínez et al (2003) was the model which best-adjusted experimental data. According to Sovová s model (1994), in S-SFE first step and SFE processes, the convection mechanism was more representative. In the S-SFE second step, the diffusion mechanism showed to be representative. S-SFE process, when realized until the depressurization step (SFE-Desp), showed to be an economically viable and profitable process on an industrial scale application, with values of extract competitive with market values, generating high quality extracts in a shorter process time
ChIA-PET2: A Versatile and Flexible Pipeline for ChIA-PET Data Analysis
No full textChIA-PET2 is a versatile and flexible pipeline for analyzing different types of ChIA-PET data from raw sequencing reads to chromatin loops. ChIA-PET2 integrates all steps required for ChIA-PET data analysis, including linker trimming, read alignment, duplicate removal, peak calling and chromatin loop calling. It supports different kinds of ChIA-PET data generated from different ChIA-PET protocols and also provides quality controls for different steps of ChIA-PET analysis. In addition, ChIA-PET2 can use phased genotype data to call allele-specific chromatin interactions. We applied ChIA-PET2 to different ChIA-PET datasets, demonstrating its significantly improved performance as well as its ability to easily process ChIA-PET raw data. ChIA-PET2 is available at https://github.com/GuipengLi/ChIA-PET2. © The Author(s) 2016.National Basic Research Program of China [2012CB316503]; National High Technology Research and Development Program of China [2012AA020401]; National Natural Science Foundation of China [91519326, 31361163004 and 31301044]; National Institutes of Health grants [HG001696, 5U01HG007919-02, 5U54HG00699604 and 5P50HG00773502]. National Basic Research Program of China [2012CB316503].School of Natural Sciences and Mathematic
Disciplina social y catolicismo en la Europa de los siglos XVI y XVII
Full text linkEn primer lugar, Po-Chia repasa la evolución que el concepto «disciplina social» ha tenido desde su aparición en 1969, cuando se usó en clave política relacionado con la monarquía absolutista que, para desarrollarse, se basa en la disciplina de la sociedad comparando las tesis de Oestreich y Weber. En segundo lugar, analiza el concepto «confesionalización», surgido de los postulados de Zeeden. Este segundo concepto analizado choca con el primero, ya que defiende la gran importancia de la teología en el nacimiento del estado absolutista. Posteriormente, el autor desarrolla brevemente los estudios más destacados que sobre ambos conceptos se han hecho hasta la actualidad así como también los desarrollos, interrelaciones, cambios, modificaciones y críticas que estos estudios han provocado en los conceptos primigenios. Finalmente, Po-Chia defiende su idea de que sin disciplina social no hay confesionalización.En primer lloc, Po-Chia repassa l'evolució que el concepte «disciplina social» ha tingut des de la seva aparició al 1969, quan s'utilitzà en clau política relacionat amb la monarquia absolutista que, per desenvolupar-se, es basa en la disciplina de la societat tot comparant les tesis d'Oestreich i de Weber. En segon lloc, analitza el concepte «confessionalització», sorgit dels postulats de Zeeden. Aquest segon concepte analitzat xoca amb el primer, ja que defensa la gran importància de la teologia en el naixement de l'estat absolutista. Posteriorment, l'autor desenvolupa breument els estudis més destacats que sobre ambdós conceptes s'han fet fins a l'actualitat així com els desenvolupaments, interrelacions, canvis, modificacions i crítiques que aquests estudis han provocat en els conceptes primigenis. Finalment, Po-Chia defensa la idea que sense disciplina social no hi ha confessionalització.In the first place, Po-Chia revises the evolution that the concept «social discipline» has had from its appearance in 1969, when it was used in political key related to the absolutist monarchy, which to be developed, bases itself on the discipline of the society, comparing the theses of Oestreich and Weber. In the second place, he analyzes the concept «confessionalisation», risen up from the postulates of Zeeden. This second analyzed concept is startling with the first, since it defends the great importance of the theology in the birth of the absolutist state. Later, the author develops briefly the more distinguished studies that on both concepts have been done up to the present as well as also the developments, interrelation, changes, modifications and critiques that these studies have promoted in the primeval concepts. Finally, Po-Chia defends his idea that without social discipline there is not «confessionalisation»
Semillas de chia oscuras y blancas cultivadas orgánicamente vs convencionalmente (Salvia hispanica L.): composición de ácidos grasos, actividad antioxidante y propiedades tecno-funcionales
Full text linkThe effects of organic and conventional crop systems on chemical composition, antioxidant activity and functional properties were evaluated in white and dark chia (Salvia hispanica L.) seeds. The organic system reduced the total protein content, and increased the total carbohydrates but did not change polyunsaturated fatty acids, total phenolic or flavonoids. Organic white chia seeds showed the best techno-functional properties. The antioxidant capacity of chia extracts varied in relation to the chemical complexity and differential rate kinetics of different assays. Extractable total phenolic acids and antioxidant capacity were better in organic white chia seeds. In this first approach, we have demonstrated that the organic white chia seed has a better total antioxidant capacity measured by direct quencher approaches than its conventionally-grown counterpart. To summarize, we conclude that the organic white chia seed could be a dietary source of antioxidants with a potential to promote health benefits in systemic functions and/or microbiota and the use of its techno-functional properties for the food industry.El efecto de los sistemas de cultivo orgánico vs convencional sobre la composición química, la actividad antioxidante y las propiedades funcionales fueron evaluadas en semillas de chía blanca y oscura (Salvia hispanica L.). El sistema orgánico redujo el contenido total de proteína, aumentó los carbohidratos totales, pero no modificó los ácidos grasos poliinsaturados, fenólicos totales y flavonoides. Las semillas orgánicas de chía blanca mostraron las mejores propiedades tecno-funcionales. La capacidad antioxidante de los extractos de chía varió en relación con la complejidad química y la cinética de velocidad diferencial de los diferentes ensayos. Los ácidos fenólicos totales y la capacidad antioxidante fueron mejores en las semillas orgánicas de chía blanca. En este primer enfoque, hemos demostrado que la semilla orgánica de chía blanca tiene una mejor capacidad antioxidante total medida por métodos directos que su contraparte cultivada convencionalmente. En resumen, indicamos que las semillas orgánicas de chía blanca podría ser una fuente dietética de antioxidantes con potencial para promover beneficios saludables en la función sistémica y/o microbiota y el uso de la propiedades tecno-funcionales para la industria alimentaria
Elucidation of lipid structural characteristics of chia oil emulsion gels by Raman spectroscopy and their relationship with technological properties
No full textEmulsion gels (EGs) offer interesting possibilities for structuring edible oils and obtaining ingredients with solid-like mechanical characteristics and depending on the ingredients used with healthier properties. In that context, the aim of this study was to develop EGs with chia oil, alginate (as cold gelling agent) and different plant derivatives (oat bran, soy protein isolate and chia flour) with both health benefits and appropriate properties for use for example as animal fat replacers in reduced-fat meat products. To that end, technological properties (pH, colour, texture, etc.) and lipid structure, determined by Raman spectroscopy, were investigated in various chia oil emulsion gels (EGs) prepared with chia oil, alginate and soy protein isolate (SEG), oat bran (OEG) or chia flour (CEG). No noticeable release of exudates was observed in chia oil EGs after processing. pH, colour and textural behaviour (evaluated as puncture force and gel strength) differed (p < 0.05) depending on the composition of the plant ingredients (soy protein, oat bran or chia flour) that contain these EGs. Raman spectroscopic results, particularly significant differences found in area and I/I, revealed differences depending on EG composition in the lipid structure and interactions in terms of lipid acyl chain mobility (order/disorder). These lipid structural characteristics of chia oil EGs correlated significantly with a specific textural feature. The results suggest that chia oil EGs could be developed for use as healthier lipid ingredients in new food systems such as healthier meat products.This research was supported under Projects AGL2014-53207-C2-1-R (MINECO), MEDGAN-CM-S2013/ABI2913 (CAM) and Intramural projects 201470E056 and 201470E073 (CSIC).Peer Reviewe
Structural and technological approach to reveal the role of the lipid phase in the formation of soy emulsion gels with chia oil
No full textThis article belongs to the Collection Feature Papers in Gel Materials.Considerable attention has been paid to emulsion gels (EGs) in recent years due to their interesting applications in food. The aim of this work is to shed light on the role played by chia oil in the technological and structural properties of EGs made from soy protein isolates (SPI) and alginate. Two systems were studied: oil-free SPI gels (SPI/G) and the corresponding SPI EGs (SPI/EG) that contain chia oil. The proximate composition, technological properties (syneresis, pH, color and texture) and structural properties using Raman spectroscopy were determined for SPI/G and SPI/EG. No noticeable (p > 0.05) syneresis was observed in either sample. The pH values were similar (p > 0.05) for SPI/G and SPI/EG, but their texture and color differed significantly depending on the presence of chia oil. SPI/EG featured significantly lower redness and more lightness and yellowness and exhibited greater puncture and gel strengths than SPI/G. Raman spectroscopy revealed significant changes in the protein secondary structure, i.e., higher (p < 0.05) α-helix and lower (p < 0.05) β-sheet, turn and unordered structures, after the incorporation of chia oil to form the corresponding SPI/EG. Apparently, there is a correlation between these structural changes and the textural modifications observed.This research was funded by the Spanish Ministry of Science and Innovation (PID2019-107542RB-C21), by the CSIC Intramural projects (grant number 201470E073 and 202070E242) and by CYTED (grant number reference 119RT0568; Healthy Meat network).Peer reviewe
Chia protein hydrolysates: characterisation and emulsifying properties
Full text linkThe evaluation of functional properties of different chia protein hydrolysates (CPH) and their application in O/W emulsions were studied. Enzymatic treatments with pepsin, pancreatin or the sequential action of pepsin–pancreatin were applied to hydrolyse a chia protein concentrate (CPC). Oil-in-water emulsions stabilised with CPC or these CPHs, with or without chia mucilage, were prepared at pH 7 or 10. Particle size, global stability, ζ-potential and rheological measurement of emulsions were determined. CPH presented higher (P ≤ 0.05) solubility and surface hydrophobicity levels, exhibiting better emulsifying properties than CPC. Emulsions with CPH presented smaller (P ≤ 0.05) droplet sizes than those with CPC. Regarding to physicochemical stability, emulsions at pH 7 were less stable than those at pH 10, showing destabilisation by creaming and coalescence. The addition of chia mucilage increased the apparent viscosity of emulsions and led to modifications in their fluid behaviour, exhibiting an interesting role as a thickening agent.Fil: Salazar Vega, Ine M.. Universidad Autónoma de Yucatán; MéxicoFil: Julio, Luciana Magdalena. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Segura Campos, Maira Rubi. Universidad Autónoma de Yucatán; MéxicoFil: Tomás, Mabel Cristina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin
Efectos metabólicos del aceite de chia en modelos experimentales: una revisión narrativa
Full text linkChia seeds are a promising food for society and the scientific community because they contain polyunsaturated fatty acids, such as alpha-linolenic acid omega-3, antioxidants, and bioactive compounds. This study aimed to investigate the metabolic effects of chia oil in experimental models which have already been described in the literature. Twenty-two preclinical studies were selected, mostly with rats. The results showed that there is still no consensus on what oil dosage is ideal for generating health benefits, with the doses ranging from 0.1g/mL to 111.1g/mL and supplementation time of 1 to 33 weeks. The studies reported increased liver omega-3 contents, an improved lipid profile, increased HDL-c, and decreased total cholesterol levels. Improved glucose tolerance and insulin sensitivity, and improved antioxidant status. It is concluded that chia oil has shown beneficial metabolic effects in organisms in preclinical studies, acting on glycemic homeostasis, lipid profiles, and oxidative stress markers.Las semillas de chía son un alimento prometedor para la sociedad y la comunidad científica porque contienen ácidos grasos poliinsaturados, como el ácido alfa-linolénico omega-3, antioxidantes y compuestos bioactivos. Este estudio tuvo como objetivo investigar los efectos metabólicos del aceite de chía en modelos experimentales descritos en la literatura. Se seleccionaron veintidos estudios preclínicos, en su mayoría con ratas. Los resultados mostraron que todavía no hay consenso sobre qué dosis de aceite es ideal para generar beneficios para la salud, con dosis que oscilan entre 0,1 g/mL y 111,1 g/mL y tiempos de suplementación de 1 a 33 semanas. Los estudios mostraron un mayor contenido de omega-3 en el hígado, un perfil lipídico mejorado, un aumento del HDL-c y una disminución de los niveles de colesterol total. Mejora de la tolerancia a la glucosa y sensibilidad a la insulina, y mejora del estado antioxidante. Se concluye que el aceite de chía ha mostrado efectos metabólicos beneficiosos en organismos en estudios preclínicos, actuando sobre la homeostasis glucémica, perfiles lipídicos y marcadores de estrés oxidativo
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