Thermoplastic Starch (TPS)‐Cellulosic Fibers Composites: Mechanical Properties and Water Vapor Barrier: A Review

Current research studies have been focusing on the procurement of environmentally friendly materials, with the aim of resolving the problems created by materials derived from petroleum. Starch is a promising biopolymer for producing biocomposite materials because it is renewable, completely biodegradable, and easily available at a low cost. Thermoplastic starch (TPS), by itself, exhibits poor mechanical properties such as low tensile strength and severe deformations, which limits its application in packaging or films. In addition, TPS presents high hygroscopicity. The use of reinforcing agents in the starch matrix is an effective means to overcome these drawbacks and several types of biodegradable reinforcements, such as cellulosic fibers, whiskers, and nanofibers, have been utilized to develop new and inexpensive starch biocomposites. This chapter provides the latest advances in green composite materials based on TPS and cellulose fibers and includes information on compositions, preparations, and the properties of “green” composite materials elaborated from TPS and cellulose fibers, with the focus on using undervalued natural resources

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Tortilla de maíz adicionado con harina de Brosimum alicastrum: propiedades fisicoquímicas y actividad antioxidante

Tortillas were obtained using nixtamalized corn flour with B. alicastrum flour at different proportions (0, 10, 20 y 30%, w/w on a dry basis). Tortillas were analyzed in relation to the chemical composition, amino acid profile, phenolic compounds, antioxidant activity and physical properties. The addition of B. alicastrum flour in tortillas increased the antioxidant activity, ash content, soluble dietary fiber, total proteins, tryptophan, phenolic compounds and total flavonoids compared to the control tortilla. The results suggest that the addition of B. alicastrum flour (10 and 2%) to corn flour increased the nutritional and functional value in tortillas while maintaining their quality (rollability, puffiness and cooking loss)Se obtienen tortillas a partir de harina de maíz nixtamalizado, al cual se le adicionaron diferentes proporciones de harina de B. alicastrum (0, 10, 20 y 30% p/p en base seca). Se analizan las tortillas en relación con la composición química, perfil de aminoácidos, compuestos fenólicos, actividad antioxidante y propiedades físicas. La adición de harina de B. alicastrum en tortillas aumentó la actividad antioxidante, el contenido de minerales, fibra soluble, proteína, triptófano, compuestos fenólicos totales y flavonoides totales comparado con la tortilla control. Los resultados sugieren que la adición de harina de B. alicastrum (10 y 20%) a la harina de maíz mejoró el valor nutricional y funcional de tortillas sin afectar su calidad (rolabilidad, grado de inflado y pérdida por cocción)

Características fisicoquímicas asociadas a calidad de carne en ovinos de pelo del sureste de México

Objective. To quantify some meat quality physicochemical traits in Longissimus thoracis from hair sheep in southeast Mexico, and test if any of these traits effectively distinguish between genotypes. Materials and methods. Animals were 18 male lambs from the Dorper (Dp,n=6) and Katahdin (Kt,n=6) breeds, and F1 Dorper sire x Katahdin dam (DpxKt,n=6) crosses. They were slaughtered at 29.5±4.2 kg average weight, at 6.2±0.2 months. Proximate composition and physicochemical analyses were run of Longissimus thoracis samples, and a canonical discriminant analysis run to identify traits that distinguished between breeds. Results. Genetic group had no effect (p>0.05) on moisture (%), crude protein (%CP) and myoglobin content. It did affect (p<0.05) intramuscular crude fat (%IMF), ash (%) and cholesterol content. IMF (4.05%) and cholesterol (92.63 mg/100 g) were highest in Kt. Ash content (1.01%) was lowest in DpxKt. Values for pH did not differ between genetic groups and were within normal limits. Cooking and drip losses were highest in DpxKt. Chroma, L* and a* values were highest in Kt, providing fresh meat from this genotype a desirable bright red color. The distinction analysis identified drip loss, IMF, Chroma and a* as effectively separating the genotypes. Conclusions. Genetic group influenced intramuscular fat, cholesterol and ash contents, and four traits served to distinguish between genotypes. These are important data for producers and marketers as they aim to create fresh meat products with specific meat quality physicochemical traits that meet demand in a diversifying market that includes grilling and gourmet cuts.Objetivo. Determinar el efecto del grupo genético sobre algunas características físico químicas asociadas a la calidad de carne en lomos (Longissimus thoracis) de ovinos de pelo del sureste mexicano. Materiales y métodos. Se evaluaron corderos machos del genotipo Dorper (Dp,n=6), Katahdin (Kt,n=6) y la cruza F1 semental Dorper x madres Katahdin (DpxKt,n=6), sacrificados con un peso promedio de 29.5±4.2 kg, a una edad de 6.2±0.2 meses. Las muestras L. thoracis fueron analizadas para determinar su composición proximal y sus características físicas. Resultados. El grupo genético no tuvo efecto (p>0.05) sobre % de humedad, % proteína cruda (%PC) y el contenido de mioglobina, por el contrario, afectó (p<0.05) al % de grasa intramuscular (%GCI), % de cenizas (%Cen) y el contenido de colesterol, siendo Kt, la que presentó un mayor contenido con 4.05% de GCI y 92.63 mg/100 g de Colesterol y DpxKt con la menor cantidad de cenizas (1.01%). Los valores de pH no mostraron diferencias estadísticas entre grupos genéticos y se encontraron dentro del rango normal. Las mayores pérdidas por cocción y pérdidas por goteo fueron para DpxKt, pero al igual que Kt tuvieron valores mayores de luminosidad (L*), rojo-verde (a*) y Cromaticidad, lo que confiere a la carne un color rojo brillante más deseable. Conclusiones. Algunas de las características fisicoquímicas estuvieron influenciadas por el grupo genético y los resultados deben ser considerados por la industria cárnica para incursionar en mercados que demanden cortes (para carne asada o platillos gourmet) con ciertas características fisicoquímicas asociadas a calidad

Tortilla de maíz adicionado con harina de Brosimum alicastrum: propiedades fisicoquímicas y actividad antioxidante

Tortillas were obtained using nixtamalized corn flour with B. alicastrum flour at different proportions (0, 10, 20 y 30%, w/w on a dry basis). Tortillas were analyzed in relation to the chemical composition, amino acid profile, phenolic compounds, antioxidant activity and physical properties. The addition of B. alicastrum flour in tortillas increased the antioxidant activity, ash content, soluble dietary fiber, total proteins, tryptophan, phenolic compounds and total flavonoids compared to the control tortilla. The results suggest that the addition of B. alicastrum flour (10 and 2%) to corn flour increased the nutritional and functional value in tortillas while maintai-ning their quality (rollability, puffiness and cooking loss).Se obtienen tortillas a partir de harina de maíz nixtamalizado, al cual se le adicionaron diferentes proporciones de harina de B. alicastrum (0, 10, 20 y 30% p/p en base seca). Se analizan las tortillas en relación con la composición química, perfil de aminoácidos, com-puestos fenólicos, actividad antioxidante y propiedades físicas. La adición de harina de B. alicastrum en tortillas aumentó la actividad antioxidante, el contenido de minerales, fibra soluble, proteína, triptófano, compuestos fenólicos totales y flavonoides totales compa-rado con la tortilla control. Los resultados sugieren que la adición de harina de B. alicastrum (10 y 20%) a la harina de maíz mejoró el valor nutricional y funcional de tortillas sin afectar su calidad (rolabilidad, grado de inflado y pérdida por cocción)

A Novel Starch from <i>Talisia floresii Standl</i> Seeds: Characterization of Its Physicochemical, Structural and Thermal Properties

Colok seed (Talisia floresii Standl) represents 80% of the total fruit weight and is obtained from trees that grow mainly in Yucatan Peninsula. The aim of this work was the physicochemical characterization from colok starch seeds as an alternative to conventional sources and to identify its characteristics for potential applications in different industrial sectors. Starch yield was 42.1% with low levels of lipids, ashes and fibers. The amylose content was 33.6 ± 1.15%. The gelatinization temperature was 85 ± 0.25 °C. Color analysis resulted in a starch with an intermediate luminosity, reflecting a dark color. Finally, in morphology, starch granule exhibited an average size of 18.7 μm, spherical, uniform and without fractures. Overall results demonstrated that isolated colok starch can be used in food products that require high processing temperatures, such as sauces, cookies, noodles, bread and food packages

Laços familiares e aspectos materiais da dinâmica mercantil na cidade de São Paulo (séculos XVIII e XIX)

Based on the family ties established within the active merchant community of the city of São Paulo through the 18th and 19th centuries, the author sets out to tell the life story of nine merchants involved in matrimonial alliances, with a focus on the transactions carried out, their sociopolitical engagement and the fortunes of their descendants. Having done that, she seeks out connections between the urban development of the city center and the activities of these businessmen by means of analyses centered on the material aspects of their lives, particularly those related to their homes and home furniture

Seminário de Dissertação (2024)

Página da disciplina de Seminário de Dissertação (MPPP, UFPE, 2022) Lista de participantes == https://docs.google.com/spreadsheets/d/1mrULe1y04yPxHUBaF50jhaM1OY8QYJ3zva4N4yvm198/edit#gid=