La cinética de cristalización de tripalmitina en trioleina una comparación de modelos

The kinetic study of crystallization in purification process has not been well, because the models has not adjusted the experimental data. In the system, tripalmitin - triolein with higher molar fractions at upper 40º C. Only crystallized tripalmitin. It uses two models, called Avrami and D. The model D adjusted very well the experimental data, the Avrami was not. At molar fraction 1, were not differences between two models, thus at this point, the nuclei formation was simultaneous, and in molar fractions lower than 1, the nuclei formation was continuous.El estudio cinético de la cristalización en procesos de purificación ha sido poco estudiado, debido a la carencia de un modelo que ajuste adecuadamente tales condiciones. En el sistema tripalmitina-trioleina a altas fracciones molares de tripalmitina y a temperaturas superiores a 40° C, solo cristaliza la tripalmitina. Se probaron dos modelos de cinética de cristalización, Avrami y D, siendo mejor el modelo D, en ajustar los datos experimentales bajo cualquier condición experimental utilizada. A fracción molar 1 de tripalmitina, los dos modelos no fueron diferentes indicando que a tal condición, la formación de núcleos era simultánea, y en las fracciones molares inferiores, la formación de núcleos era continua

Chemical composition of biomass generated in the guava tree pruning

Psidium guajava L. (Myrtaceae) is a native plant of Central America and is now widely cultivated in many tropical regions of the world for the fruit production. In Mexico, in the guava orchards common practices to control fruit production are: water stress, defoliation and pruning. In this study, we report the chemical composition of the biomass (branches and leaves) generated in the pruning practices. The results ranged as follows: pH (4.98-5.88), soda solubility (39.01-70.49 %), ash (1.87-8.20 %); potassium and calcium were the major inorganic elements in ash. No heavy metals were detected in the studied samples; total solubility (15.21-46.60 %), Runkel lignin (17.77-35.26 %), holocellulose (26.56 -69.49 %), α-cellulose (15.53-35.36 %), hemicelluloses (11.02-34.12 %), tannins in aqueous extracts (3.81-9.06 %), and tannins in ethanolic extracts (3.42-15.24 %)

Polyphenolic Profile, Sugar Consumption and Organic Acids Generation along Fermentation of Infusions from Guava (Pisidium guajava) by the Kombucha Consortium

The kombucha beverage is typically prepared from black tea, sweetened with sucrose, inoculated with previously fermented liquid broth and/or tea fungus pellicle, and incubated. Alternative sources have been used for kombucha beverages. Guava leaves have been used for long time as traditional medicine. It is found in many commercially available botanical supplements in form of decoction, milled and used as comprises. They are rich in polyphenolic compounds. Several changes are produced during fermentation of the beverages. The main objective of the present work is to characterize fermentation process of guava leaves infusions by kombucha and studying possible chemical changes in their polyphenolic profile. Infusions from guava leaves were prepared and fermented by the kombucha consortium. The pH, titrable acidity, polyphenolic compounds, sugar consumption, organic acid along the fermentation was made by UPLC-ESI-MS. Kombucha from Camellia sinensis (CS) was made as a control. Higher rate of sucrose consumption was observed for Kombucha made with CS, also, higher production of organic acids (acetic and succinic acid) was observed too. Both behaviors were related to the content of glucose. The flavan-3-ols were diminishing along the fermentation time, with the exception of epigallocatechin in Camellia sinensis, Flavan-3-ol content in Guava leaves was low. Higher content of dicaffeoyl quinnic acid was observed for both systems in special for CS, falling after a maximum peak; minor constituents of hydroxycinnamic acids were stable along the fermentation for both systems

Caracterización de dos variedades de girasol con potencial para la producción de aceite extraídos con hexano e isopropanol

The sunflower oil require of an extraction process that reduce the amount of impurities, and the use of a solvent that has not implications over the environment. An alternative is the use of the isopropyl alcohol. In this work was studied the extraction conditions of two experimental varieties of sunflower Madero-91 and Cianoc-2, the controls were hexane and Sunflower seed variety Victoria. It was found differences on the physical characteristics and in the dispersion of the physical measures from the three varieties used. The percent yield of crude oil extracted with isopropyl alcohol was not different of the obtained with hexane. The level of free fatty acids was higher in the oils extracted with isopropyl alcohol than the oils extracted with hexane, no differences was found in the amount of malonic aldehide.El aceite de girasol requiere de un proceso de extracción que reduzca el contenido de impurezas y del uso de un solvente que no atente contra el ambiente. Una alternativa es el empleo del isopropanol. En la presente investigación se estudiaron las condiciones de extracción de aceite de dos variedades de girasol, Madero 91 y Cianoc-2, y como control al girasol variedad Victoria y el hexano. Se encontraron diferencias en cuanto a características físicas de las variedades estudiadas, así como en la dispersión de las mediciones físicas. El rendimiento en porcentaje de aceite crudo con el alcohol isopropílico no difirió del obtenido con hexano. El nivel de ácidos grasos libres fue superior en los aceites extraídos con isopropanol. No se encontraron diferencias en cuanto al contenido de aldehído malónico

Avances en las investigaciones sobre la encapsulación mediante gelación iónica: una revisión sistemática

Encapsulation, a technology that creates a barrier between a compound of interest and the environment, improves the physicochemical stability of products during processing and/or storage. Therefore, it helps to reduce the degradation of compounds of interest, masks undesirable odors and flavors, controls the release of the bioactive compound, and can increase its bioaccessibility and bioavailability. The objective of this review was to collect and discuss recent scientific literature about encapsulation by ionic gelation of bioactive compounds, microorganisms, and enzymes, as well as its use in different applications of scientific and/or industrial interest in several fields. A literature review was carried out in indexed databases using descriptors such as capsule size, encapsulation efficiency, mixture matrices, sodium alginate, and ionic gelation. The results show that using of this kind of encapsulation offers variable advantages regarding the bioavailability of bioactive compounds, the stability of different compounds, the improvement of physical characteristics, the release of compounds, and the protection against adverse environmental effects. In conclusion, the ionic gelation method can have a wide range of applications to encapsulate food ingredients, microorganisms, drugs, etc. This review can guide further research into ionic gelation because it examines the diversity of its applications.La encapsulación es una tecnología que proporciona barreras entre los compuestos de interés en un producto y el medio ambiente. Ella brinda una mejor estabilidad fisicoquímica durante el procesamiento y/o almacenamiento del producto, por lo tanto, ayuda a tener una menor degradación de los compuestos de interés, enmascara olores y sabores indeseables, controla la liberación del principio activo y puede incrementar su bioaccesibilidad y su biodisponibilidad. El objetivo de esta revisión fue recopilar y discutir la literatura reciente enfocada en investigaciones científicas sobre la encapsulación mediante gelación iónica de compuestos bioactivos, de microorganismos, de enzimas y su uso en diferentes aplicaciones de interés científico y/o industrial. La revisión bibliográfica se realizó en las principales bases de datos indexadas, utilizando descriptores como tamaño de cápsula, eficiencia de encapsulación, matrices mixtas, alginato de sodio y gelación iónica. De acuerdo con los resultados se observó que la utilización de este tipo de encapsulación presenta ventajas muy variables que se centran en la mejora de diversos factores como la biodisponibilidad de compuestos bioactivos, estabilidad de diferentes compuestos, características físicas, liberación del compuesto de interés y la protección contra efectos ambientales adversos. En conclusión, existe una amplia gama de aplicaciones que puede tener la metodología de gelación iónica para encapsular ingredientes alimenticios, microorganismos y fármacos, entre otros. Finalmente, el estudio pretende que esta revisión sea de utilidad en la dirección de investigaciones sobre gelación iónica, debido a la diversidad de aplicaciones abordadas durante la investigación

Inhibitory effects of Buddleja scordioides (salvilla) leaves on digestive enzymes and carbohydrate absorption in vivo

The effects of Buddleja scordioides (BsLI) leaf infusions on digestive enzymes and carbohydrate absorption were evaluated. The BsLI yield was 21.64 %. In addition, a chemical characterization was carried out identifying hydroxybenzoic acids, hydroxycinnamic acids, flavonols, flavanones and flavones. In vitro studies were performed to determine the inhibitory action of BsLI on lipase, α-amylase, and α-glucosidase. Then, in rats, oral starch tolerance tests (OSTT) were carried out using BsLI at a dose of 9.5 mg/kg body weight. Results showed moderate inhibition of lipase and α-glucosidase, but greater inhibition of α-amylase compared to positive controls. During the OSTT trial, the group receiving BsLI showed a significant reduction in glucose levels compared to the negative control group. Bioactive compounds, such as naringenin, luteolin, quercetin, and coumaric acid, were identified after BsLI administration. Furthermore, the consumption of BsLI was safe and showed antioxidant activity like Trolox. In conclusion, BsLI may have an enhanced effect on glucose metabolism by inhibiting carbohydrate absorption. DOI: https://doi.org/10.54167/tch.v17i2.122

Effect of Aqueous Extracts of Quercus resinosa on the Mechanical Behavior of Bigels

Quercus resinosa leaves are rich in polyphenol compounds, however, they are unstable to several chemical and physical factors that limit their activity. Several methods have been developed to solve such problems, among which bigels can be mentioned and obtained using hydrogels and oleogels. The mechanical characterization of this type of materials is by using rheological methods. Although the use of these methods is well documented, the Carreau-Yasuda model has been little used to evaluate the effect of polyphenols on the mechanical behavior of bigels. Therefore, bigels were obtained from hydrogels (guar gum/xanthan gum, 0.5/0.5% w/v) and oleogels (sesame oil/sorbitan monostearate 10% w/w). Micrographs, linear viscoelasticity range, frequency sweep, and single shear tests were performed. The data were analyzed using ANOVA and Tukey test (p < 0.05); micrographs showed linear relationship between polyphenols concentration and droplet size. Liquid fraction of bigels showed a pseudoplastic behavior, while the parameters of Carreau-Yasuda model showed that the highest value of the complex viscosity at zero shear was at the lowest concentration of extract; the relaxation time presented the lowest value at higher concentrations of extracts. These results indicate that the presence of polyphenols modifyes the mechanical behavior of bigels

Organogeles como mejoradores del perfil lipídico en matrices cárnicas y lácteas

The structuring of edible oils, through organogelation, has a promising potential in food applications, when used as substitutes for saturated fat in some meat and dairy products of high consumption demand, in order to improve their lipid profile. Organogels are viable for this substitution, which is related to the nutritional improvement demanded by the current consumer, due to the negative effect of saturated fats on health. The objective of this review was to analyze different formulations of organogels, applied in meat-dairy matrices and their impact on the final properties of such food products, implemented as a substitute for saturated fat. The findings indicate that the replacement of saturated fat, by this type of materials, mainly affects the physicochemical properties, modifies the original flavor of the food and improves its lipid profile; However, they still do not meet the expectations of the final consumer due to the unique qualities of solid fat, which represents the main barrier to overcome for its application in an industrial scale production and sale to the market. It is necessary to develop new formulations, similar to those qualities, to achieve  consumer  acceptance.La estructuración de aceites comestibles, a través de la organogelación, tiene un potencial prometedor en aplicaciones alimenticias, al ser utilizadas como sustitutos de grasa saturada en algunos productos cárnicos y lácteos de alta demanda de consumo, con la finalidad de mejorar su perfil lipídico, el cual está relacionado con la mejora nutricional que demanda el consumidor actual, por el efecto negativo que tienen las grasas saturadas en la salud. El objetivo de este trabajo fue analizar diferentes formulaciones de organogeles, aplicados en matrices cárnicas-lácteas, y su impacto en las propiedades finales de tales productos alimentarios, implementados como sustituto de grasa saturada. Se encontró que la sustitución de grasa saturada, por este tipo de materiales, afecta principalmente las propiedades fisicoquímicas, modifica el sabor original de los alimentos y mejora su perfil lipídico; sin embargo, aún no permiten cumplir las expectativas del consumidor final, por las cualidades únicas que ofrece la grasa sólida, lo que representa la principal barrera a superar para su uso en una producción a escala industrial y venta al mercado. Es necesario desarrollar nuevas formulaciones, que asemejen dichas cualidades, para alcanzar la aceptación de los consumidores